Which ic amplifier is better? - Android Head-Units

Hello, I wanted to ask which ic amplifier would be the best for me for the car in terms of sound music,I have some doubts between the Tda 7851 or Tda 7838 or Toshiba Tcb001, by the way I have an external amplifier of kicker 250.1. Thanks!

adir 25 said:
Hello, I wanted to ask which ic amplifier would be the best for me for the car in terms of sound music,I have some doubts between the Tda 7851 or Tda 7838 or Toshiba Tcb001, by the way I have an external amplifier of kicker 250.1. Thanks!
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This depends on what you have right now. The most common hardware mod is TDA7850 with a 10,000 mf capacitor. Personally, I disconnect it from internal power altogether and drive it with a 17v-18v 10A power supply. Bear in mind that TDA7850 requires proper cooling so be ready to add additional heatsinks and a temperature-controlled fan (you don't want the fan to be on all the time, only when cooling is required). Example in the pics.
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If you have an external amplifier and it's good (at least 300 real Watts), then I would remove the internal amplifier chip altogether and instead optimize the hardware for using an external amp.
More info on the mod itself can be found here and here.

iceblue1980 said:
This depends on what you have right now. The most common hardware mod is TDA7850 with a 10,000 mf capacitor. Personally, I disconnect it from internal power altogether and drive it with a 17v-18v 10A power supply. Bear in mind that TDA7850 requires proper cooling so be ready to add additional heatsinks and a temperature-controlled fan (you don't want the fan to be on all the time, only when cooling is required). Example in the pics.
View attachment 5391107...View attachment 5391105
If you have an external amplifier and it's good (at least 300 real Watts), then I would remove the internal amplifier chip altogether and instead optimize the hardware for using an external amp.
More info on the mod itself can be found here and here.
Click to expand...
Click to collapse
Ok, I understand, in the case that I have an external amplifier how do I optimize the hardware for using an external amp?

adir 25 said:
Ok, I understand, in the case that I have an external amplifier how do I optimize the hardware for using an external amp?
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Click to collapse
Guides can be found here and here.
This will require the removal of the internal amp and soldering other components onto the motherboard

iceblue1980 said:
Guides can be found here and here.
This will require the removal of the internal amp and soldering other components onto the motherboard
Click to expand...
Click to collapse
Removal of the TDA power amplifier is not necessary, you could consider grounding pin 4 to place TDA7388 into standby and decouple signal inputs via 1k resistor to RCA leads for connection to external amp.
Another option could be to cut or lift TDA power supply leads. However, leaving the TDA in place will not affect audio.
Despite what the Russian mods suggest, soldering 1k resistors, carefully and supporting with a small amount of suitable glue is OK.

adir 25 said:
Hello, I wanted to ask which ic amplifier would be the best for me for the car in terms of sound music,I have some doubts between the Tda 7851 or Tda 7838 or Toshiba Tcb001, by the way I have an external amplifier of kicker 250.1. Thanks!
Click to expand...
Click to collapse
There is so little difference (other than being mostly counterfeit or knockoffs) between these Power Amplifier ICs there is no "best".
If you want a real and measurable difference, install an external power Amp.

marchnz said:
There is so little difference (other than being mostly counterfeit or knockoffs) between these Power Amplifier ICs there is no "best".
If you want a real and measurable difference, install an external power Amp.
Click to expand...
Click to collapse
Real TDA7850 (properly cooled) powered by 17-18v supply with 10,000 mf cap, with proper power and grounding cabling with correctly configured Viper4Android will perform on a level where no external amp will be able to complete when it comes to price vs sound quality.
If you choose external amp then you'll need to throw in a DSP unit as well. All that will cost more than some are willing to spend.
YD7388 and TDA7388 are complete crap however.

iceblue1980 said:
Real TDA7850 (properly cooled) powered by 17-18v supply with 10,000 mf cap, with proper power and grounding cabling with correctly configured Viper4Android will perform on a level where no external amp will be able to complete when it comes to price vs sound quality.
If you choose external amp then you'll need to throw in a DSP unit as well. All that will cost more than some are willing to spend.
YD7388 and TDA7388 are complete crap however.
Click to expand...
Click to collapse
Ok, I got it, I have a dilemma between these two -

adir 25 said:
Ok, I got it, I have a dilemma between these two -View attachment 5392433
Click to expand...
Click to collapse
None of these are YT921xxx or Rockchip based type, so personally I wouldn't know how to do any modifications on any of them

iceblue1980 said:
Real TDA7850 (properly cooled) powered by 17-18v supply with 10,000 mf cap, with proper power and grounding cabling with correctly configured Viper4Android will perform on a level where no external amp will be able to complete when it comes to price vs sound quality.
If you choose external amp then you'll need to throw in a DSP unit as well. All that will cost more than some are willing to spend.
YD7388 and TDA7388 are complete crap however.
Click to expand...
Click to collapse
Unfortunately, the datasheet shows a different perspective, however goldern ears may vary. If you like it, that's great.

adir 25 said:
Ok, I got it, I have a dilemma between these two -View attachment 5392433
Click to expand...
Click to collapse
As I said earlier, there's little to NO difference between the power amps they use, except that they're mostly counterfeit devices, so it's *luck of the draw* what you end up with.
If your concers are audio quality, these Chinese knockoffs are not for you. Also, doing misinformed things like running the power amp at manufacturer rated maximum supply and fitting a giant heatsink to in in hope of it lasting longer than a short period of time - won't help either. I had originally typed 'dumb', but realized that it's not polite.

Just to be super clear on this question: Which amplifier is better?
The answer is none.
The power amps used in these devices are all so close in terms of output power, the difference is insignificant.
Wanting quality Audio? The cheapest units are not for you, with the more expensive units not necessarily offering any better "quality".
Wanting power to drive your speakers/annoy - purchase external power amplifier(s).

marchnz said:
As I said earlier, there's little to NO difference between the power amps they use, except that they're mostly counterfeit devices, so it's *luck of the draw* what you end up with.
If your concers are audio quality, these Chinese knockoffs are not for you. Also, doing misinformed things like running the power amp at manufacturer rated maximum supply and fitting a giant heatsink to in in hope of it lasting longer than a short period of time - won't help either. I had originally typed 'dumb', but realized that it's not polite.
Click to expand...
Click to collapse
Clearly you have not had any experience testing TDA7388 or YD7388 with true TDA7850-system described above side by side.
Only relying on datasheets is like trying to understand what sound will be like by reading datasheets of speakers...
Please refrain from confusing people who are most probably on budget, trying to get the best out of their Android Head Units.
Max conditions for any electronic device can be successfully applied with proper modding to support the output. They will not break.
Many times the shortfall is the cooling, not the power output capacity. And it's not "just heatsinks", it's an end-to-end temperature-controlled cooling system.
I will agree on that if you can afford a proper external amp and DSP, that that is a better choice. And many of these units can be optimized to deliver a respectable performance with external gear.

iceblue1980 said:
Clearly you have not had any experience testing TDA7388 or YD7388 with true TDA7850-system described above side by side.
Only relying on datasheets is like trying to understand what sound will be like by reading datasheets of speakers...
Please refrain from confusing people who are most probably on budget, trying to get the best out of their Android Head Units.
Max conditions for any electronic device can be successfully applied with proper modding to support the output. They will not break.
Many times the shortfall is the cooling, not the power output capacity. And it's not "just heatsinks", it's an end-to-end temperature-controlled cooling system.
I will agree on that if you can afford a proper external amp and DSP, that that is a better choice. And many of these units can be optimized to deliver a respectable performance with external gear.
Click to expand...
Click to collapse
Testing, interesting.
How were the before and after tested and against which ICs.
No, reading IC datasheets is not "like trying to understand what sound will be like by reading datasheets of speakers".
One could however make cabinet and crossover decisions based on speaker datasheets, that is possible.
If at the end of the design, your speakers added some sort of magical sound to the reproduction, the calculations are in error and the design is a failure.
This discussion is however like comparing two cheap rubber bands and arguing one is better because you can stretch it further.
Since you mentioned speakers, running a speaker beyond xmax is analogous to operating the amp IC at its Vmax - impending failure.

marchnz said:
Testing, interesting.
How were the before and after tested and against which ICs.
No, reading IC datasheets is not "like trying to understand what sound will be like by reading datasheets of speakers".
One could however make cabinet and crossover decisions based on speaker datasheets, that is possible.
If at the end of the design, your speakers added some sort of magical sound to the reproduction, the calculations are in error and the design is a failure.
This discussion is however like comparing two cheap rubber bands and arguing one is better because you can stretch it further.
Since you mentioned speakers, running a speaker beyond xmax is analogous to operating the amp IC at its Vmax - impending failure.
Click to expand...
Click to collapse
When data sheets clearly shows THD >10% and skyrocketing above 100W output. You don't need any test to know that it will not sound very nice powering 4-8 speakers and a subwoofer!
But it might sound ok with efficient stock speakers.
For undistorted power you need an external amp. But these units are rather noisy and garbage in equals garbage out...

Allan_Hun said:
When data sheets clearly shows THD >10% and skyrocketing above 100W output. You don't need any test to know that it will not sound very nice powering 4-8 speakers and a subwoofer!
But it might sound ok with efficient stock speakers.
For undistorted power you need an external amp. But these units are rather noisy and garbage in equals garbage out...
Click to expand...
Click to collapse
Subwoofer will pull the most amps which is why it's highly recommended to have an active sub, which let's face it - most car audio lovers will already have. Even a compact underseat subwoofer like Kenwood KSC-SW11 150W will make quite a difference even in an SUV sized vehicle.
A trimmed TDA7850 setup in a up to 8x (4+Ohm) stock speakers + active sub, will deliver some respectable results in combination with a properly configured Viper4Android.
With passive sub, I probably wouldn't bother as it would choke TDA7850 even with the suggested mod. Simple physics.
I tested a 4 × 4Ohm speaker setup with a midsize passive sub and it wasn't awesome. Was okay but barely.

iceblue1980 said:
Subwoofer will pull the most amps which is why it's highly recommended to have an active sub, which let's face it - most car audio lovers will already have. Even a compact underseat subwoofer like Kenwood KSC-SW11 150W will make quite a difference even in an SUV sized vehicle.
A trimmed TDA7850 setup in a up to 8x (4+Ohm) stock speakers + active sub, will deliver some respectable results in combination with a properly configured Viper4Android.
With passive sub, I probably wouldn't bother as it would choke TDA7850 even with the suggested mod. Simple physics.
I tested a 4 × 4Ohm speaker setup with a midsize passive sub and it wasn't awesome. Was okay but barely.
Click to expand...
Click to collapse
Stock speakers have tiny motors designed for 15 RMS watts.
But if you want something better you need power. 50W is better and 100W is even better. But if you care about sound guality you definitely don't want 20% of the output to be distortion. So a tiny single ic amp is not up for the task.
So if you want cheap sound quality purchase a power amp. Lot's of nice used amps available for 100$. So that is the route I would recommend instead of trying to mod the internal amp.
But if anyone really want to spend their time modding I'm not stopping anyone...

Allan_Hun said:
Stock speakers have tiny motors designed for 15 RMS watts.
But if you want something better you need power. 50W is better and 100W is even better. But if you care about sound guality you definitely don't want 20% of the output to be distortion. So a tiny single ic amp is not up for the task.
So if you want cheap sound quality purchase a power amp. Lot's of nice used amps available for 100$. So that is the route I would recommend instead of trying to mod the internal amp.
But if anyone really want to spend their time modding I'm not stopping anyone...
Click to expand...
Click to collapse
Well, getting an external amp will still require hardware modding of the cheaper Android Heads Unit for optimal output and you'll need to throw in a DSP unit to at least partially offset not having Viper4Android.
I think if you put it all together it'll make more sense than comparing watts and units/components one by one.
The sad part of it all is that no Android Head Unit, not even the most expensive ones can deliver any meaningful audio experience. I compared the sound quality of a $800 Android Head Unit and a $100 one and it was barely noticeable.
The newer Qualcomm Android Head Units come without internal amp but require almost no modding to deliver good output. Granted, these new units utilise the fibre connection so not really a fair comparison.
I'm actually using one myself with an external Harman Kardon setup - and it's almost good enough but I'm really missing Viper Still looking for a hardware alternative but it would require quite a stack of hardware... DSP, EQ, Dynamics FX unit etc etc..

iceblue1980 said:
Well, getting an external amp will still require hardware modding of the cheaper Android Heads Unit for optimal output and you'll need to throw in a DSP unit to at least partially offset not having Viper4Android.
I think if you put it all together it'll make more sense than comparing watts and units/components one by one.
The sad part of it all is that no Android Head Unit, not even the most expensive ones can deliver any meaningful audio experience. I compared the sound quality of a $800 Android Head Unit and a $100 one and it was barely noticeable.
The newer Qualcomm Android Head Units come without internal amp but require almost no modding to deliver good output. Granted, these new units utilise the fibre connection so not really a fair comparison.
I'm actually using one myself with an external Harman Kardon setup - and it's almost good enough but I'm really missing Viper Still looking for a hardware alternative but it would require quite a stack of hardware... DSP, EQ, Dynamics FX unit etc etc..
Click to expand...
Click to collapse
I used to have a 100$ android HU feeding 3 amps through a Dayton DSP.
At low volume the s/n ratio was quite bad, but at normal listening volume it wasn't bad and I could not hear it with the engine running.
So I would like to know what you think needs to be improved about the preouts and how?
What is dynamics FX and what do you miss from viper?

Allan_Hun said:
I used to have a 100$ android HU feeding 3 amps through a Dayton DSP.
At low volume the s/n ratio was quite bad, but at normal listening volume it wasn't bad and I could not hear it with the engine running.
So I would like to know what you think needs to be improved about the preouts and how?
What is dynamics FX and what do you miss from viper?
Click to expand...
Click to collapse
I normally test the sound in my workshop as I have different car speakers and home speakers setup so I will hear literally everything... Car engine noise is therefore not present.
The radio sound is not great but can be improved by removing a few internal bypass capacitors and changing some others to much more powerful ones. The radio sound is better on units with NXP radio chip that supports RDS but frankly I'd rather listen to DAB or Internet Radio as that sounds goes through the "normal audio channels".
There are ways of "cleaning up" the output from RCA's by modding internal components. I'm yet to test it but can tell you for sure that the RCA outputs are "noisy". I compared the audio quality of Kenwood and Sony pre-outs side by side with one of the $100 Chinese Androids, and at least in lab environment, the difference was noticeable.
Viper4Android is a as powerful audio processing tool as any piece of software can deliver on an Android. Coming from a studio recording background (used to be an audio recording engineer and composer), I see this as a complete tool to perfect the car audio by softening the bad and boosting the good.
Dynamics FX for example allows you to utilise compression of certain frequencies at certain volume levels so that no matter of how quiet or loud the overall volume is, you sound stage will be perfectly balanced. It's a bit like fluent EQ.
And there are a number of other modules that will allow things like adaptive stereo imaging, frequency boost, distortion prevention (I have pushed TDA7850 to it's limits with no audible distortion), noise cancelling, delays, reverbs - pretty much any studio effect you can think of.
It is a complex tool but once done right, it's really impressive.
To give you an example, it took me 8 hours to properly calibrate the sound in our previous car that had one if these Mediatek Android Head units (modded to the teeth of course). Using stock BOSE speakers and 1 underseat sub in a fairly large SUV, it was uncomparable with the stock amp setup. Yes I spent a month modding the unit itself but for $200 I paid for the head unit and any spare parts for modding, it sounded like a 20-30 times more expensive audio setup and the best part was that it was a powerful Android as far as head units go.

Related

Joying SQ

I've been reading mixed reviews on the SQ of these units. I've read about the mod and it sounded like the sound just got louder. But is the sound fine and just flat sounding or is it something else? I was thinking a line driver would help or maybe it would just amplify the noise. I have some decent audio equipment and I don't want to feel I'm not getting the full potential out of them. I do use some WAV and FLAC files. I guess I can't tell if people are commenting on the on board audio or from their amps hooked up to the RCAs.
I have a 2016 Jeep Wrangler Unlimited. I had the factory 430N head unit, with the base 8 speaker system. I replaced 4 of the 8 speakers with Kickers and add a Kicker sub and amp (amp is just for the sub), and it sounded better but still not great.
THis weekend I added a Joying Jeep specific unit, and I feel like the sound of the overall system is vastly improved. I think it sounds pretty good, I primarily use Google Play Music and Pandora.
CadillacMike said:
I have a 2016 Jeep Wrangler Unlimited. I had the factory 430N head unit, with the base 8 speaker system. I replaced 4 of the 8 speakers with Kickers and add a Kicker sub and amp (amp is just for the sub), and it sounded better but still not great.
THis weekend I added a Joying Jeep specific unit, and I feel like the sound of the overall system is vastly improved. I think it sounds pretty good, I primarily use Google Play Music and Pandora.
Click to expand...
Click to collapse
Did you add a line driver at all to bump up the voltage on the pre-outs?
splxtreme said:
Did you add a line driver at all to bump up the voltage on the pre-outs?
Click to expand...
Click to collapse
I did not add anything. The sub and amp are built for Jeep, so it might be a little weird:
http://www.kicker.com/SWRA411
have any of you measure the pre-out voltage on the joying? On my tonghai create 2nd gen unit, pre-out voltage is only 1V. What this means is you will have a high noise floor going into your amplifier. Then your amp will amplify any noise your pre-outs have picked up. So if you use a line driver to raise the pre-out voltage prior to going into your amp, the higher voltage actually LOWERS the noise floor, hence eliminating noise that your RCAs may pick up.
My advice is you MUST have a line driver if you plan to use these units w/ a external amp. The difference will be night and day, particularly in the higher frequencies, where amplified noise is more pronounced.
They are dirt cheap too. I bought one on amazon for ~$30. It is actually a 3-way cross-over/line driver combo. It feels cheap but does it's job as a line driver very well.
edit: I say the above from personal experience, as I literally spent months trying to figure out why my tweeters always sounded so terrible. Line driver did the trick. Now I have clean highs and more clear, vibrant mids. I don't seem to notice much difference in my bass, so apparently noise interference isn't audible in the lower frequencies.
explain "line driver" to a stupid dumb dumb person, not me of course, just so other people understand
CadillacMike said:
explain "line driver" to a stupid dumb dumb person, not me of course, just so other people understand
Click to expand...
Click to collapse
line driver is just another word for a voltage step-up device. It's simply a way to increase the voltage of the RCA pre-outs coming out of your HU. Most amplifiers can read all the way down to about .5V pre-outs no problem. So a low pre-out voltage isn't much of a problem in theory.
But, an amplifier is also a voltage step-up device. It's going to take the pre-out voltage and multiply it by a pre-determined amount. You can adjust that amount by modifying gain. Your speakers are rated for a certain RMS power (80W for instance). So, if your speakers are 4 ohms rated for 80W RMS, the formula for the voltage it needs from your amp is sqrt(80 * 4) = 18V. So for your speaker to get the full rated power, it needs at least 18V from your amp. Higher pre-amp voltage = easier to reach the rated output to your speakers, since less gain is required.
Also, I mentioned noise floor. It's explained well here -
http://www.glasswolf.net/papers/preouts.html
It's not so easy to explain in laymans terms, but just know that higher voltage pre-outs = higher signal to noise ratio (SNR), meaning more signal & less noise = lower noise floor.
The article does mention however that having too high of a pre-out voltage is not good either, as it can lead to clipping. Best to buy an adjustable line driver (the $30 amazon model I bought had this feature... this one -
https://www.amazon.com/SX310-Pre-Am...70255121&sr=8-1&keywords=electronic+crossover). Most devices that accept pre-outs max out at around 6V, some as low as 4V. So don't crank up the line driver to max... I leave mine around 75-80%.
Hope that helps.

Decent audio upgrade: Adding cost effective low profile amp

Just found this cool amp the other day. Sorry if it's been mentioned before.
For those who don't know, head units have an amp, per say, built in to them. However, most are junk and just large enough to get you by. Even the ones that have high claims. Like 50watts X 4, but your really only getting like 15 watts per channel. A lot of people don't want to mess with all the wiring and connections and cost/space issues with installing a traditional outboard amp in their trunk. I came across this little bugger that has great reviews and may be the ticket for some of you. It's an amp, but with a slim profile and able to hide in your dash behind your headunit. Idk, just thought I'd share.
https://www.amazon.com/Alpine-KTP-445U-4-channel-Power-Amplifier/dp/B003VVYL46
well i clicked on this thinking i would not be interested, but now I'm thinking I might get this
hurtgen said:
Just found this cool amp the other day. Sorry if it's been mentioned before.
For those who don't know, head units have an amp, per say, built in to them. However, most are junk and just large enough to get you by. Even the ones that have high claims. Like 50watts X 4, but your really only getting like 15 watts per channel. A lot of people don't want to mess with all the wiring and connections and cost/space issues with installing a traditional outboard amp in their trunk. I came across this little bugger that has great reviews and may be the ticket for some of you. It's an amp, but with a slim profile and able to hide in your dash behind your headunit. Idk, just thought I'd share.
https://www.amazon.com/Alpine-KTP-445U-4-channel-Power-Amplifier/dp/B003VVYL46
Click to expand...
Click to collapse
45RMS, not terribly small there.
FYI: Those head units that say 40 or 50 watts x4 aren't lying -- they're quoting MAX, not RMS.
Generally speaking, you don't need more than about 40-50 max. If you send too much power, you will damage your speakers. The speakers that cars come with are a reasonable match with the FACTORY radio, which will give you around 40 max. Sustained use at even factory radio's highest output will dramatically shorten the life of the speakers, AND, is enough to cause permanent hearing loss.
Some aftermarket speakers can take a higher amount of input power, but they aren't necessarily LOUDER. They actually require more power to generate the same volume. Now of course, I'm not going into the discussion about which *sounds better*, rather just about raw power. My only point, is that if you have factory speakers, then even this amp is overkill. If you want to improve the sound QUALITY, then of course, by all means, knock yourself out. But don't forget to upgrade your speakers as well, or you're just throwing the money down the toilet.
The number one cause for blown speakers is driving them with an underpowered amplifier resulting in clipping. It's much more advisable to over power a speaker than to under power, which is the case in most cars in Stock form. This amp would be a great addition to a vehicle with either stock speakers or entry level coaxial or even some components. In my situation I'm running a pair of Infinity Kappa 60.11cs rated at 90 watts rms each @ 2ohm and powering them with a Rockford Fosgate p300x2 putting out 150 watts rms @ 2ohms per channel.
Reading the reviews, it sounds like many people are installing this with stock speakers in place and are having great results.

Bad sound quality on Android units fixed with good external amp?

HI
All of the bad sound quality issues I've read about in regards to various Chinese Android head units seem to be related to the internal amplifier/chip from what I can gather.
If you use the pre-outs and run a good quality external amplifier, is the pre-out signal clean enough to sound good, or does it still sound bad, just with more power behind it?
Thanks!
--ElmoTheDestroyer
Joying has these new units with some sort of enhanced amplifier and EQ that at least on paper look way better what other Chinese units offer... in fact no other Chinese manufacturer made the effort to offer something better... all go the same route... basic and cheap so kudos for Joying that they are trying something different.
Now we need confirmation from buyers that the new amplif is indeed better....
edit said:
Joying has these new units with some sort of enhanced amplifier and EQ that at least on paper look way better what other Chinese units offer... in fact no other Chinese manufacturer made the effort to offer something better... all go the same route... basic and cheap so kudos for Joying that they are trying something different.
Now we need confirmation from buyers that the new amplif is indeed better....
Click to expand...
Click to collapse
Yeah, I was looking at picking one of those up, I'm just curious, if I'm not happy with how that sounds, if using a good external amp will actually provide "really good" sound quality vs. the internal amp. I know that using a crappy preamp source can give pretty bad results even on a good amp, but at the same time, the preamp section of these units might be clean enough to provide a good usable signal to an external amp.
Though it would be cool if the new internal amp Joying is using is actually good! Be nice to not have to spend money on an external amp if I can avoid it...
ElmoTheDestroyer said:
Yeah, I was looking at picking one of those up, I'm just curious, if I'm not happy with how that sounds, if using a good external amp will actually provide "really good" sound quality vs. the internal amp. I know that using a crappy preamp source can give pretty bad results even on a good amp, but at the same time, the preamp section of these units might be clean enough to provide a good usable signal to an external amp.
Though it would be cool if the new internal amp Joying is using is actually good! Be nice to not have to spend money on an external amp if I can avoid it...
Click to expand...
Click to collapse
Don't set your set your hopes way too high, after all we are talking about 300-400$ units here. If the sound quality is the top priority these are not the ones to look at, with or without an external amplif. Very good sound quality is expensive. Most (like me) pick these up for the convenience of having an navigation, backup camera, access to various streaming apps and so on... the list is long. My original Ford headunit is head and shoulders above these Chinese units when it comes to sound quality, FM Radio reception/ sound quality.... but it also lacks so many features that you find in a modern headunit that I find them useful enough to give up on the original headunit high sound quality.
edit said:
Don't set your set your hopes way too high, after all we are talking about 300-400$ units here. If the sound quality is the top priority these are not the ones to look at, with or without an external amplif. Very good sound quality is expensive. Most (like me) pick these up for the convenience of having an navigation, backup camera, access to various streaming apps and so on... the list is long. My original Ford headunit is head and shoulders above these Chinese units when it comes to sound quality, FM Radio reception/ sound quality.... but it also lacks so many features that you find in a modern headunit that I find them useful enough to give up on the original headunit high sound quality.
Click to expand...
Click to collapse
lol, yeah, I'm not expecting super high quality sound... I have an older android unit in my truck now, so I know how it feels to have crappy sound.. Just debating if it's worth spending the money on an external amp to help things out... Not sure if it'd be worth the expense/trouble to install, or if it would just make crappy muddy sound louder.
Love the convenience of these units though, especially compared to my 20 year old stock CD player, talk about a huge technology update!
Suppose I'll just get one of these new Joying units with the new digital amp and hope for the best...
Thanks again for the info!
I have one and should have it running in the next week. It's my understanding that if you enable an external amp with the new units the surround sound is disabled and the old app is enabled. In other words you lose all the fancy adjustments if you use an external amp. I have a few cars and one of them will use an external amp and I'm only just hoping for less heat from the new design. On another car I'm hoping to bypass the original amp with the new unit and drive it right from the joying unit.
Of course sound is pretty subjective so I'm doubtful even if I say its better that that is meaningful to anyone else in their car etc. A the end of the day I like decent sound, but the android functionality is my primary need. One of my cars is a Honda Element. This thing has so much road noise a person might be throwing their money away if they went with premium quality.
400 bucks can either be a lot for someone or less significant for others.
well now the Sony Android Auto unit is down to $400. I was actually never unhappy with the sound of my Joying, but holy **** the sound is dramatically improved with the Sony:
https://forum.xda-developers.com/an...-xav-ax100-t3647891/post73238321#post73238321
However, I do miss the full functionality of Android, so I'll be going back to either Joying or Seicane. But after having that Sony, i may look into adding an amp or a DSP or something to try to get that sound
i got the new Joying with the Amp and DSP, and I think it sounds pretty great.
CadillacMike said:
i got the new Joying with the Amp and DSP, and I think it sounds pretty great.
Click to expand...
Click to collapse
Separate amp or the new class D amp internal?
pounce said:
Separate amp or the new class D amp internal?
Click to expand...
Click to collapse
It has the internal amp, one with the gold plate on the back
CadillacMike said:
i got the new Joying with the Amp and DSP, and I think it sounds pretty great.
Click to expand...
Click to collapse
Can you please tell us more? Maybe compared to the Sony?
The old Joying is ok as long as you install Viper.
Do not compare onder units with Joying Intel based units...
I have all amplified on my car, with Joying 2Gb Intel unit (not the new ones with digital amplifier), but applyied some on stock audio cars and sound is not worst than pioneer, kenwood, sony 100-200€ units.
But to made the sound better, disable LOUD and on Car Settings app, on the code protected menu, on balance sound option, put the sound bars on 0 (zero). Now you can volume up without distortion and the sound will be more clear.
ElmoTheDestroyer said:
lol, yeah, I'm not expecting super high quality sound... I have an older android unit in my truck now, so I know how it feels to have crappy sound.. Just debating if it's worth spending the money on an external amp to help things out... Not sure if it'd be worth the expense/trouble to install, or if it would just make crappy muddy sound louder.
Love the convenience of these units though, especially compared to my 20 year old stock CD player, talk about a huge technology update!
Suppose I'll just get one of these new Joying units with the new digital amp and hope for the best...
Thanks again for the info!
Click to expand...
Click to collapse
edit said:
Can you please tell us more? Maybe compared to the Sony?
The old Joying is ok as long as you install Viper.
Click to expand...
Click to collapse
I got the install done very late last night.
So I only got to listen on the way in to work, and I don't have everything set up yet. But I think it sounds about as good as the Sony.
Beast Mode activated
Here are some pics
Can you please share .APK for this amplifier app ?
ElmoTheDestroyer said:
HI
All of the bad sound quality issues I've read about in regards to various Chinese Android head units seem to be related to the internal amplifier/chip from what I can gather.
If you use the pre-outs and run a good quality external amplifier, is the pre-out signal clean enough to sound good, or does it still sound bad, just with more power behind it?
Thanks!
--ElmoTheDestroyer
Click to expand...
Click to collapse
No, the problem isn't with the amplifiers. The amplifiers they install may be somewhat small, but they're not bad units. The problem is in what they send TO the amplifiers, which will be exactly the same if you use an external amplifier.
All that an amplifier actually does, is makes the sound LOUDER. If the sound that you are amplifying is full of noise, artifacts, and clipping, then those *painful* bits of sound will also be amplified.
I know this thread is a blast from the past, but in searching xda i am having a hard time finding if any of these android headunit make clean sound out the RCA.
I have a Sofia unit from about 2 years ago, and have never been able to get rid of whine of the engine across rpm range (especially if engine is running with headlights on) i have a good grounding kit under the hood, quality 4 gauge power and ground to amp, tested PAC SNI-1 Noise Isolators on both front and rear RCA, have even tried a Axxess AX-ANR1000 Power Noise Filter. All to no avail.
Is there any units that are better for clean output?
merdok said:
I know this thread is a blast from the past, but in searching xda i am having a hard time finding if any of these android headunit make clean sound out the RCA.
I have a Sofia unit from about 2 years ago, and have never been able to get rid of whine of the engine across rpm range (especially if engine is running with headlights on) i have a good grounding kit under the hood, quality 4 gauge power and ground to amp, tested PAC SNI-1 Noise Isolators on both front and rear RCA, have even tried a Axxess AX-ANR1000 Power Noise Filter. All to no avail.
Is there any units that are better for clean output?
Click to expand...
Click to collapse
Filtering noise out of a system like that can be a bit of a daunting challenge.
There are a ton of different places where the noise can be brought into your radio from your car;
1) ANY electrical connection between your car and your radio. This includes power+, power-, and even all the different *signal* wires, like ACC, headlights, reverse, etc.
2) RF. This is a really challenging one to deal with, because if your alternator is blasting out a whole bunch of RF noise at a frequency in the range of 20-40,000 Hz, and if that RF gets picked up by an audio wire pre-amplifier, then the amplifier will take that noise, amplify it, and play it on your speakers.
You've tried a power noise filter.
Have you tried connecting the ACC line to the filtered side of that filter instead of the ignition? Have you tried disconnecting ALL of the other signal lines coming into the radio?
Now about the RF part.
Here is the thing. If you're using the pre-amp audio outputs, then that means that you are bringing the pre-amp audio signal OUTSIDE of the protection of the metal box (faraday cage).
The SNI-1 ground loop isolator that you've tried isn't going to do a damned thing if your problem is RF noise. In fact, it is an idiotic part altogether since all it actually does is it converts a signal from one ground reference to a possibly different ground reference. Instead of that, what you should be doing is making sure that there is no potential difference in the ground reference level of the two parts being connected -- specifically, the radio, and the amplifier.
Two things you can do to help with this;
1) Add a big cable from the amplifier chassis to the radio's metal box.
2) Use the highest quality and SHORTEST audio cables possible.
Also... have you confirmed that the amplifier you are using isn't actually the source of the noise?
96carboard said:
Filtering noise out of a system like that can be a bit of a daunting challenge.
There are a ton of different places where the noise can be brought into your radio from your car;
1) ANY electrical connection between your car and your radio. This includes power+, power-, and even all the different *signal* wires, like ACC, headlights, reverse, etc.
2) RF. This is a really challenging one to deal with, because if your alternator is blasting out a whole bunch of RF noise at a frequency in the range of 20-40,000 Hz, and if that RF gets picked up by an audio wire pre-amplifier, then the amplifier will take that noise, amplify it, and play it on your speakers.
You've tried a power noise filter.
Have you tried connecting the ACC line to the filtered side of that filter instead of the ignition? Have you tried disconnecting ALL of the other signal lines coming into the radio?
Now about the RF part.
Here is the thing. If you're using the pre-amp audio outputs, then that means that you are bringing the pre-amp audio signal OUTSIDE of the protection of the metal box (faraday cage).
The SNI-1 ground loop isolator that you've tried isn't going to do a damned thing if your problem is RF noise. In fact, it is an idiotic part altogether since all it actually does is it converts a signal from one ground reference to a possibly different ground reference. Instead of that, what you should be doing is making sure that there is no potential difference in the ground reference level of the two parts being connected -- specifically, the radio, and the amplifier.
Two things you can do to help with this;
1) Add a big cable from the amplifier chassis to the radio's metal box.
2) Use the highest quality and SHORTEST audio cables possible.
Also... have you confirmed that the amplifier you are using isn't actually the source of the noise?
Click to expand...
Click to collapse
Thank!
I can confirm it's not the amp itself by a headphone to rca cable from my phone into amp w/o noise.
1.) I need to try running a wire from amp ground to cage of hu. Think better to attach to ground of the case or attach to powerline filter? Going to test with bridge both wires of premium speaker wire. That should be plenty right?
2.) only wires that are a bit longer than needed are the rca. Might be 2ft slack because amp is under passenger seat.
Sent from my ONEPLUS A6003 using Tapatalk
---------- Post added at 02:07 PM ---------- Previous post was at 01:24 PM ----------
Wow I think the wire from amp to hu case is going to be the fix! I never thought of that or needed in my years.
Sent from my ONEPLUS A6003 using Tapatalk
merdok said:
Thank!
I can confirm it's not the amp itself by a headphone to rca cable from my phone into amp w/o noise.
1.) I need to try running a wire from amp ground to cage of hu. Think better to attach to ground of the case or attach to powerline filter? Going to test with bridge both wires of premium speaker wire. That should be plenty right?
2.) only wires that are a bit longer than needed are the rca. Might be 2ft slack because amp is under passenger seat.
Sent from my ONEPLUS A6003 using Tapatalk
---------- Post added at 02:07 PM ---------- Previous post was at 01:24 PM ----------
Wow I think the wire from amp to hu case is going to be the fix! I never thought of that or needed in my years.
Sent from my ONEPLUS A6003 using Tapatalk
Click to expand...
Click to collapse
Hello,
I have the same problem "permanent noise in my Android unit". If I understand well, you have solve the problem with a wire from amp to HU. Could you explain more about this fix or a diagram?
Thks a lot

bottom line on Android head units and connecting amps and subs

I've actually purchased a few of these over the years, mostly because they were very vague on this specific feature. Given many of these units are identical just rebranded copies it's hard to sort things out.
The following is based on countless hours searching the web and 4 or 5 personal purchases of these Android head units. If any of this is incorrect please tell me because I have been desperately searching for one due to BMWs incessant need to one off everything.
In my experience the bottom line is no. Android head units do not offer genuine sub support. Yes you can use the rear output and a line converter or run the signal into the high level inputs on your amp (if it has it) but there is still a very simple a basic problem. You still won't have the needed components and or firmware to properly run it. Specifically frequency control, crossover or even a 7 band eq on the unit. I only found one that offered that last and it was janky to say the least (more probably offer the eq now but still very subpar) assuming you can run v4a on the unit that may clear some up but that was written for head phones not a 4 or more speaker system.
Another point is most mainstream headunits, pioneer, Kenwood, alpine heck even boss have 4v rca preout and signal conditioners not to mention both high and low-pass crossovers.
Unfortunately to my knowledge these Chinese Android suppliers have really missed the ball. Yes they offer some cool features but car audio guy's spend many thousands of dollars on these systems and to be honest I have a avh-4500NEX in my 325xi and since it mirrors wirelessly as well as Android auto and car play wireless it provides excellent sound.
Major difference my NEX $1800.00 us brand new these Android's I've seen get spendy but mostly right around 150-400. But you get what you pay for.
The biggest bonus I found though was you can put them anywhere since they are mostly just and inch or two deep.
If I missed the mark please let me know and if you could send a link to where I can pick up a decent one. The I-Drive in my 535i is making a stereo upgrade next to impossible
this is the honest **** i been scouring for... as a AV guy everyone keeps telling me go daisaita blah blah blah but everyone here seems to not have ears or know what they are talking about when it comes to sound... my original gut was to pick up a NEX but i got side tracked with Atoto and the rest because everyone talks out their ass about how amazing they are... with no clue about their soul purpose
they do have
b1n4ry said:
this is the honest **** i been scouring for... as a AV guy everyone keeps telling me go daisaita blah blah blah but everyone here seems to not have ears or know what they are talking about when it comes to sound... my original gut was to pick up a NEX but i got side tracked with Atoto and the rest because everyone talks out their ass about how amazing they are... with no clue about their soul purpose
Click to expand...
Click to collapse
They have amazing abilities for instance the iDrive in my 525i is old and outdated and these Android HU are the only option and they are fully functional and compatible which no mainstream HU can claim that I'm aware of. But I'll deal with old and crappy and tap the harness for a signal for my amp before I'll downgrade on sound quality.
You can use an Android successfully IF you install an EQ and probably noise filter but there goes the saving you would have seen.
Spdif out to dsp-amp is possible with Joying for example. SQ shouldn't be problem with it.
Kelynaw said:
If I missed the mark please let me know and if you could send a link to where I can pick up a decent one. The I-Drive in my 535i is making a stereo upgrade next to impossible
Click to expand...
Click to collapse
I've had pioneer, Kenwood, Alpine, Blaupunkt and a few others and you haven't missed the mark at all. The audio quality on these Chinese head units is just not comparable and the RCA output voltages (1.4 volts) are standards from 15 or 20 years ago. And yes... they are NOT true sub outputs.
Now having said that, it doesn't mean that you can't bring the audio quality up to par. It does however require some extra money and extra components. I don't run Dasaita's sub outputs but rather have an active electronic crossover which can generate a sub output and I run that plus the Dasaita's front/rear outputs through an AXXESS dsp sound processor before the signals go into the amps.
It's certainly a bit of extra money spent on top of it all, but IMO, worth it because these Android head units beat out the traditional Kenwood's and pioneer's in just about every other respect.
It WOULD be nice however if these Chinese manufacturers started paying a bit more attention to audio quality at the end of the day.
Bob_Sanders said:
I've had pioneer, Kenwood, Alpine, Blaupunkt and a few others and you haven't missed the mark at all. The audio quality on these Chinese head units is just not comparable and the RCA output voltages (1.4 volts) are standards from 15 or 20 years ago. And yes... they are NOT true sub outputs.
Now having said that, it doesn't mean that you can't bring the audio quality up to par. It does however require some extra money and extra components. I don't run Dasaita's sub outputs but rather have an active electronic crossover which can generate a sub output and I run that plus the Dasaita's front/rear outputs through an AXXESS dsp sound processor before the signals go into the amps.
It's certainly a bit of extra money spent on top of it all, but IMO, worth it because these Android head units beat out the traditional Kenwood's and pioneer's in just about every other respect.
It WOULD be nice however if these Chinese manufacturers started paying a bit more attention to audio quality at the end of the day.
Click to expand...
Click to collapse
except that axxess unit costs more than the 4/64gb headunit itself... USA MSRP: $422.00 USD
b1n4ry said:
except that axxess unit costs more than the 4/64gb headunit itself... USA MSRP: $422.00 USD
Click to expand...
Click to collapse
HUH??
$279 on ebay
https://www.ebay.com/itm/Axxess-AX-...241633?hash=item445ecc93e1:g:194AAOSwUKRfRo-R
My new Dasaita cost $586
https://www.aliexpress.com/item/4001197637149.html?spm=a2g0s.9042311.0.0.554d4c4duJ2EgH
Bob_Sanders said:
HUH??
$279 on ebay
https://www.ebay.com/itm/Axxess-AX-...241633?hash=item445ecc93e1:g:194AAOSwUKRfRo-R
My new Dasaita cost $586
https://www.aliexpress.com/item/4001197637149.html?spm=a2g0s.9042311.0.0.554d4c4duJ2EgH
Click to expand...
Click to collapse
DSP
https://axxessinterfaces.com/product/AXDSP-X
unit i was looking at
https://www.aliexpress.com/item/4001244806859.html?spm=2114.12010612.8148356.2.51e67ea7IZbacK
Dash Kit
https://www.scosche.com/2003-to-2007-honda-accord-integrated-touchscreen-control-colution-dash-kit
Apparently you haven't played with any of the recent Joyings....You also obviously don't have much experience with different cell phones out there either.
Ok, fine....show me a Pioneer, Alpine, Kenwood, etc that can run Google Maps, Waze, Firefox, Gaia Navigation, Torque Pro, APRS Droid, etc natively, right on the unit....just ONE unit, from ANY of the "big name" manufacturers...they just plain don't exist. Not a single one that runs Android natively, or anything else other than their own, completely closed souce, proprietary OSes that we can't do anything with beyond what comes installed on them from the factory. Don't like their nav app, launcher, or general interface? Tough schmitt...
I've said the same thing for many years...I'd be HAPPY to drop a $1,000USD or more on a solid unit from a major manufacturer that runs Android natively. Or even a Linux based OS, that I can add additional apps to. Hell, I was dropping a thousand plus on putting a touch screen in my dash connected to a PC tower in the back YEARS before these factory double din units hit the market. Some company like Pioneer drops one of them, and I'd be one of the first in line screaming "take my money!!".
Screen mirroring isn't an option for everyone either, as screen mirroring is largely based on Miracast. Especially so for anyone with a Google phone, such as my Pixel. Google has gone out of their way to limit or even eliminate that ability to push more sales of their lousy Chromecast devices, and they have stripped Miracast support out of the core Android as of version 6 (Marshmallow). If your phone supports screen mirroring, that's because whoever made it added Miracast support back in themselves. Android Auto is also a rather lousy compromise for many of us, such as myself, that want to run alternative apps. If it wasn't coded to run within Android Auto, it generally ain't happening which is the case for the navigation app that I use for off road purposes.
I've tried several different Pioneer double din touch screens with several different Android phones. Never once was I able to get screen mirroring/mirrorlink to work correctly to truly screen mirror the phone. Only the crippled Android Auto worked...which is what ultimately pushed me into completely going with these Chinese Android head units.
That said, the Joying JY-UO135N4GS - https://www.joyingauto.com/joying-l...avigation-system-with-built-in-4g-module.html that I have in the truck right now does have a 16 band EQ built in, F&R RCAs as well as a dedicated Sub RCA output, though it's a single. I haven't put a meter on it to verify voltage, but I'm guessing it's around 2V based on gain settings on the amp compared to other head units that I've known to have 2V outputs. A LOT of "brand name" head units today still come with 2V outputs. Also has both LPF and Subsonic filters on the sub output, as well as independent HPF crossovers on F&R channels. I currently have my subs set to 30Hz-100hz, fronts set to 80Hz high pass, and rears at 135Hz high pass (yeah..blame Chevy and their piss poor design on their trucks). Subs are a pair of JBL GTO 12s fed by a Kenwood monoblock amp. Door speakers are Infinity Kappa 6.5s, rears are factory 4x10s.
Is the sound quality on par with the Pioneer head unit that it replaced? No. Can I hear the difference at 75mph over the wind and diesel engine noise? Nope. Maybe I'd hear the difference if I put one of these Joyings in my Cadillac...Do I plan to replace this Joying with a Pioneer/Alpine/Kenwood/etc? Wait for it....has not ever once crossed my mind. I also have a Joying in my Suzuki Samurai, and am shopping for another Android unit for my Suzuki Grand Vitara.
urbex said:
Apparently you haven't played with any of the recent Joyings....You also obviously don't have much experience with different cell phones out there either.
Ok, fine....show me a Pioneer, Alpine, Kenwood, etc that can run Google Maps, Waze, Firefox, Gaia Navigation, Torque Pro, APRS Droid, etc natively, right on the unit....just ONE unit, from ANY of the "big name" manufacturers...they just plain don't exist. Not a single one that runs Android natively, or anything else other than their own, completely closed souce, proprietary OSes that we can't do anything with beyond what comes installed on them from the factory. Don't like their nav app, launcher, or general interface? Tough schmitt...
I've said the same thing for many years...I'd be HAPPY to drop a $1,000USD or more on a solid unit from a major manufacturer that runs Android natively. Or even a Linux based OS, that I can add additional apps to. Hell, I was dropping a thousand plus on putting a touch screen in my dash connected to a PC tower in the back YEARS before these factory double din units hit the market. Some company like Pioneer drops one of them, and I'd be one of the first in line screaming "take my money!!".
Screen mirroring isn't an option for everyone either, as screen mirroring is largely based on Miracast. Especially so for anyone with a Google phone, such as my Pixel. Google has gone out of their way to limit or even eliminate that ability to push more sales of their lousy Chromecast devices, and they have stripped Miracast support out of the core Android as of version 6 (Marshmallow). If your phone supports screen mirroring, that's because whoever made it added Miracast support back in themselves. Android Auto is also a rather lousy compromise for many of us, such as myself, that want to run alternative apps. If it wasn't coded to run within Android Auto, it generally ain't happening which is the case for the navigation app that I use for off road purposes.
I've tried several different Pioneer double din touch screens with several different Android phones. Never once was I able to get screen mirroring/mirrorlink to work correctly to truly screen mirror the phone. Only the crippled Android Auto worked...which is what ultimately pushed me into completely going with these Chinese Android head units.
That said, the Joying JY-UO135N4GS - https://www.joyingauto.com/joying-l...avigation-system-with-built-in-4g-module.html that I have in the truck right now does have a 16 band EQ built in, F&R RCAs as well as a dedicated Sub RCA output, though it's a single. I haven't put a meter on it to verify voltage, but I'm guessing it's around 2V based on gain settings on the amp compared to other head units that I've known to have 2V outputs. A LOT of "brand name" head units today still come with 2V outputs. Also has both LPF and Subsonic filters on the sub output, as well as independent HPF crossovers on F&R channels. I currently have my subs set to 30Hz-100hz, fronts set to 80Hz high pass, and rears at 135Hz high pass (yeah..blame Chevy and their piss poor design on their trucks). Subs are a pair of JBL GTO 12s fed by a Kenwood monoblock amp. Door speakers are Infinity Kappa 6.5s, rears are factory 4x10s.
Is the sound quality on par with the Pioneer head unit that it replaced? No. Can I hear the difference at 75mph over the wind and diesel engine noise? Nope. Maybe I'd hear the difference if I put one of these Joyings in my Cadillac...Do I plan to replace this Joying with a Pioneer/Alpine/Kenwood/etc? Wait for it....has not ever once crossed my mind. I also have a Joying in my Suzuki Samurai, and am shopping for another Android unit for my Suzuki Grand Vitara.
Click to expand...
Click to collapse
If you are fine with sub par audio Then your opinion doesn't matter
The #1 purpose above all the bull**** you rambled on about is SOUND that's the purpose of an aftermarket head unit... Regardless of additional features
b1n4ry said:
If you are fine with sub par audio Then your opinion doesn't matter
The #1 purpose above all the bull**** you rambled on about is SOUND that's the purpose of an aftermarket head unit... Regardless of additional features
Click to expand...
Click to collapse
It's already been stated that audio quality is not the best. It's also been made clear that for some extra bucks and a few more components you CAN have your cake and eat it too. Now if you wish not to go that far then why are you here? Go to the pioneer forums.
As for the purpose of an aftermarket head unit.... yesteryear it WAS all about sound. Now it's more about central information centers. All kinds of information at your fingertips... and these Chinese units just beat the crap out of ANY of the traditional units as general information centers. Try hard as you can to make a traditional head unit do something to this level of detail and customization:
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
Now.. do I have to put some extra money in making the sound better? Yup, sure do, but to my eyes it's worth it.
I´m running my Joying still from speaker out to Match M5DSP. SQ is even now better than with stock HU (PSA MyWay) that I used to feed M5DSP. I don´t hear any problems and I´ve been hifi-guy nearly 30 years.
Why is it not a true subwoofer output? I have a 1500w rms amp connected to the green subwoofer output and a dayon max mx12 and its clear as day. My only problem is my hengcheng which is like a teyes c3 clone only has front rca output and I want to leave my front speakers on the tda7851 built in amplifier and connect my rear speakers to a 200w amp in the back. But if I use the front rca out I will loose fader control cuz the system will think my rears are front speakers. What about the output voltage? I don't have a line out converter and everything sounds fine.
Kelynaw said:
I've actually purchased a few of these over the years, mostly because they were very vague on this specific feature. Given many of these units are identical just rebranded copies it's hard to sort things out.
The following is based on countless hours searching the web and 4 or 5 personal purchases of these Android head units. If any of this is incorrect please tell me because I have been desperately searching for one due to BMWs incessant need to one off everything.
In my experience the bottom line is no. Android head units do not offer genuine sub support. Yes you can use the rear output and a line converter or run the signal into the high level inputs on your amp (if it has it) but there is still a very simple a basic problem. You still won't have the needed components and or firmware to properly run it. Specifically frequency control, crossover or even a 7 band eq on the unit. I only found one that offered that last and it was janky to say the least (more probably offer the eq now but still very subpar) assuming you can run v4a on the unit that may clear some up but that was written for head phones not a 4 or more speaker system.
Another point is most mainstream headunits, pioneer, Kenwood, alpine heck even boss have 4v rca preout and signal conditioners not to mention both high and low-pass crossovers.
Unfortunately to my knowledge these Chinese Android suppliers have really missed the ball. Yes they offer some cool features but car audio guy's spend many thousands of dollars on these systems and to be honest I have a avh-4500NEX in my 325xi and since it mirrors wirelessly as well as Android auto and car play wireless it provides excellent sound.
Major difference my NEX $1800.00 us brand new these Android's I've seen get spendy but mostly right around 150-400. But you get what you pay for.
The biggest bonus I found though was you can put them anywhere since they are mostly just and inch or two deep.
If I missed the mark please let me know and if you could send a link to where I can pick up a decent one. The I-Drive in my 535i is making a stereo upgrade next to impossible
Click to expand...
Click to collapse
They are mostly the same but not all the same, I.e. MTCD with MCU mod sub out.
Yes, line level is 1.5-2v RMS not 4v as car audio mostly is.
Your post doesn't list "Android units" so cant tell what your test units were.
Why is it not a true subwoofer output? I have a 1500w rms amp connected to the green subwoofer output and a dayon max mx12 and its clear as day. My only problem is my hengcheng which is like a teyes c3 clone
marchnz said:
They are mostly the same but not all the same, I.e. MTCD with MCU mod sub out.
Yes, line level is 1.5-2v RMS not 4v as car audio mostly is.
Your post doesn't list "Android units" so cant tell what your test units were.
Click to expand...
Click to collapse
Which one is
Excuse my ignorance, I don't do high end stereo builds for cars(home theater yes).
Just curious, if you're trying to put out that kind of wattage and care that much about crystal sound, why aren't you using spdif(optical or coax) to output digital from your stereo regardless of brand. Then your Head unit is for the features/apps and screen and your high end equip is for signal processing?
Because the optical is 5.1 so a DAC would be mono output to each speaker, and there isn't a digital rca spdif or optical that is stereo. I thought about doing that and just using y cables but not with it really the signal wouldn't be any better just less chance of interference and I have none. An amp with optical starts around 1k unless you go aliexpress or something. My amp topsolidgear 1600w 1 ohm stable as tested by wiliston audio on YouTube is $150. My Dayton MX12-22 12" subwoofer was $140. I have it running 600w @ 4 ohm and its already crazy. After I break it in I may switch to 1 ohm and get even louder. My speakers are coaxial ds18 3 way black diamonds ($39) and my rear speakers are component ds18 6.5 with 3.5" bullet tweeters with built in crossover ($70) so it's a budget system. But it sounds great. All my audio is high resolution lossless flac files and the dsp does a great job. The 32 band equalizer let's me adjust subwoofer frequency and speaker frequency so I can turn my speakers off between 30_whatever hertz and set my sub anywhere from 30_70 hz range. It also has time delay and surround function and turns my amp on and off with a trigger wire amongst some other settings I haven't figured out yet.
Can't figure out what bass enhancement does. Bass filter is to filter bass from speakers and surround is to adjust timing.
Here is a pic.
CaliBurr said:
Because the optical is 5.1 so a DAC would be mono output to each speaker, and there isn't a digital rca spdif or optical that is stereo. I thought about doing that and just using y cables but not with it really the signal wouldn't be any better just less chance of interference and I have none. An amp with optical starts around 1k unless you go aliexpress or something. My amp topsolidgear 1600w 1 ohm stable as tested by wiliston audio on YouTube is $150. My Dayton MX12-22 12" subwoofer was $140. I have it running 600w @ 4 ohm and its already crazy. After I break it in I may switch to 1 ohm and get even louder. My speakers are coaxial ds18 3 way black diamonds ($39) and my rear speakers are component ds18 6.5 with 3.5" bullet tweeters with built in crossover ($70) so it's a budget system. But it sounds great. All my audio is high resolution lossless flac files and the dsp does a great job. The 32 band equalizer let's me adjust subwoofer frequency and speaker frequency so I can turn my speakers off between 30_whatever hertz and set my sub anywhere from 30_70 hz range. It also has time delay and surround function and turns my amp on and off with a trigger wire amongst some other settings I haven't figured out yet.
Click to expand...
Click to collapse
"there isn't a digital rca spdif or optical that is stereo"
not sure I understand this statement? Digital is stream is whatever is on it the stream. I send stereo over optical all the time in home theater(well I used too, it's OLD now ;-) Yes technically each speaker would be mono(it's channel) maybe I'm missing something.
I understand your point on cost, but if you already have the amp you want with solid RCA then just use a 50 dollar 4.1 or 5.1 DAC to RCA
It will skip the "crappy" DAC in the the HU and avoid interference(sorry but from what I read they ALL have it). I know both mine do.
The only reason I can think it will still be bad is if they are still doing DAC then reversing it for the optical. Again I have not tested the optical on the one I have with it as my stock system doesn't do spdif or even RCA.

Android head unit change parts

Hello,
I have bought a 2 DIN Android 10 head unit for my car.
I found the only product matching with my car (alfa romeo 147) to fit properly.
But I am very disappointed about what is inside.
First specifications do not match (4 gb RAM instead of 8, 800x480 instead of 1024x600...)
In addition sound is not very good.
I wonder if it is possible to change parts like
- Screen , to increase resolution
- Sound board , to have a better audio quality
- Increase RAM ...
Is there standard connection, like in a PC, allowing us to change some elements ?
Thank you for your responses
theog11 said:
Hello,
I wonder if it is possible to change parts like
- Screen , to increase resolution
- Sound board , to have a better audio quality
- Increase RAM ...
Is there standard connection, like in a PC, allowing us to change some elements ?
Thank you for your responses
Click to expand...
Click to collapse
Screen size has nothing to do with screen resolution: GIYF ...
Sound quality can get increased with an EQUALIZER app: GIYF ...
RAM may get increased physically, but will not be detected. You may try to install a SWAP memory ( virtual RAM ): GIYF ...
To manage Android OS from PC via USB cable you use ADB.
Thank you for your re
jwoegerbauer said:
Screen size has nothing to do with screen resolution: GIYF ...
Sound quality can get increased with an EQUALIZER app: GIYF ...
RAM may get increased physically, but will not be detected. You may try to install a SWAP memory ( virtual RAM ): GIYF ...
To manage Android OS from PC via USB cable you use ADB.
Click to expand...
Click to collapse
For screen resolution, with a higher resolution you are able display more information with a same size screen. If you don't believe me try to connect your PC to your TV and play with resolution.
Sound quality is not really increased by the equalizer APP. You can tune a little but if your device is poor, you will never have good sound
It sounds like there is enough wrong here so that it's not worth it. Just a new higher res screen will set you back a pretty penny.
Either live with it or return/sell it and start over with a better known brand.
Sorry but all incorrect answers. Every single aspect of the unit can be improved. Especially sound quality.
It will require hardware modding as well as software modding but it is more than doable.
We run a charity project where I bring these £100 units to a level of products costing many thousands, only spending £50-£100 in materials.
One of the mods we do is to replace the need of external amplifier and DSP altogether.
You can check out extrememod.co.uk for more ideas, particularly the FAQ section.
iceblue1980 said:
Sorry but all incorrect answers. Every single aspect of the unit can be improved. Especially sound quality.
It will require hardware modding as well as software modding but it is more than doable.
We run a charity project where I bring these £100 units to a level of products costing many thousands, only spending £50-£100 in materials.
One of the mods we do is to replace the need of external amplifier and DSP altogether.
You can check out extrememod.co.uk for more ideas, particularly the FAQ section.
Click to expand...
Click to collapse
Charity is lovely I respect that. But do you seriously believe that your mod can truly replace the need for a power amp? If so then please tell how you mod the headunits output to deliver 500+ watts of clean RMS power required to power a sub+woofers+midbass+tweeters with sufficient headroom in a noisy environment like a car?
And regarding the DSP. Sure any DSP with time alignment is better than no TA but a nice dedicated DSP offers so many features that no mods will bring these headunits.
So please stop spreading false claims about 100$ mod magically transforming these headunits into sql competition winning material.
Ok I checked Extrememod.co.uk and that page was just about as untruthful as Chinese sellers on AliExpress. Quote: "These units come equipped with a powerful built-in audio amplifier"
Very powerful indeed -and miraculously only require a tiny winy power cable AND runs fine with a 10A fuse. A truly Nobel prize worthy achievement!
Allan_Hun said:
Charity is lovely I respect that. But do you seriously believe that your mod can truly replace the need for a power amp? If so then please tell how you mod the headunits output to deliver 500+ watts of clean RMS power required to power a sub+woofers+midbass+tweeters with sufficient headroom in a noisy environment like a car?
And regarding the DSP. Sure any DSP with time alignment is better than no TA but a nice dedicated DSP offers so many features that no mods will bring these headunits.
So please stop spreading false claims about 100$ mod magically transforming these headunits into sql competition winning material.
Ok I checked Extrememod.co.uk and that page was just about as untruthful as Chinese sellers on AliExpress. Quote: "These units come equipped with a powerful built-in audio amplifier"
Very powerful indeed -and miraculously only require a tiny winy power cable AND runs fine with a 10A fuse. A truly Nobel prize worthy achievement!
Click to expand...
Click to collapse
All great points. Now let me respond to some of them.
1. I believe you missed the core point of it all - we build Android head units for audiophiles on budget. This essentially means all the people looking to have great sound at the smallest cost while keeping full functionality of an Android device.
2. Your comment on "500W RMS" and "tiny tiny cables" is irrelevant. Why? Because your sound will only be as good as the source. An Android Head unit will often output very poor sound from pre-outs. We therefore maximise the internal amp and surrounding electronics, advising folks not to use external amps and DSP's. Most of the cars we build for use 18 AWG speaker cables already, same as in the ISO harness. We do however use 16 AWG power cables with proper grounding.
3. I'm sorry but I'm yet to see a DSP processor that offers what Viper4Android does. Especially within feasible cost range.
4. The units we build have their TDA7850 amps running at 18v, not 12v - obviously with bespoke cooling to support the high temps. In most cars, true 200W output will be more than enough.
To summarize, we started this project to build all-in-one Android Head Units that offer everything an audiophile would want without spending thousands of dollars, while keeping all that an Android can offer. We had a good look around and found absolutely nothing in the Android Head unit space that did not require the user to sacrifice at least something, whether it's the sound, the handsfree quality, the UI, Android apps limitations etc.
The real reason for why no manufacturer is building units such as this - is the cost. In mass-production, it would simply be too expensive. Luckily we can work with what we've got and replace components with much better ones, hardware and software alike.
We are also looking into optimizing these units specifically for people that want to use external amps and DSP's. This too requires quite a lot of modding to ensure the pre-outs deliver as high quality output as possible. We'll be looking for audio pro's to test them and give us feedback. You can apply on our site if you're interested and located near London, UK.
iceblue1980 said:
Sorry but all incorrect answers. Every single aspect of the unit can be improved. Especially sound quality.
Click to expand...
Click to collapse
I didn't say it can't be done. I said it's not worth it. There is a difference.
If you want to mod and improve, then start with a good quality base. This head unit is not that.
iceblue1980 said:
4. The units we build have their TDA7850 amps running at 18v, not 12v - obviously with bespoke cooling to support the high temps. In most cars, true 200W output will be more than enough.
Click to expand...
Click to collapse
Replacing (and using) internal amps is a useless and fruitless endeavor. There are far more options available in external amps, quality and ease of installing when going with external amps. Indeed, if you are on a budget then external amps (and dsp's if need be) are the better way to go because you can upgrade a bit at a time.
Does an external amp increase audio quality ?
I think if source is not very good, external amp will just allow more power output, but what about quality ?
How to check if head unit has DSP ? Mine is supposed to have but I want to verify
theog11 said:
Does an external amp increase audio quality ?
I think if source is not very good, external amp will just allow more power output, but what about quality ?
How to check if head unit has DSP ? Mine is supposed to have but I want to verify
Click to expand...
Click to collapse
An internal amp does not increase audio quality any more or less than an external amp does, so it is a moot and irrelevant question. If you have bad audio quality going into an internal amp, then the outcome is exactly the same. Regardless of what amp you use (internal or external), if the audio quality is bad going into the amp, then it will be bad going out of the amp too.
What an external connection with external amps does is allow more flexibility in the quality of amps used, the number of amps used, and the power involved. You can also add external dsp's if you wish.
Bob_Sanders said:
I didn't say it can't be done. I said it's not worth it. There is a difference.
If you want to mod and improve, then start with a good quality base. This head unit is not that.
Click to expand...
Click to collapse
It is a charity project so Besides, we're focusing on 8227L units primarily. They are cheap and pretty much made for low-cost modding with more than respectable outcomes.
Bob_Sanders said:
Replacing (and using) internal amps is a useless and fruitless endeavor. There are far more options available in external amps, quality and ease of installing when going with external amps. Indeed, if you are on a budget then external amps (and dsp's if need be) are the better way to go because you can upgrade a bit at a time.
Click to expand...
Click to collapse
But then I would go back to the point 1 I made - the bottleneck is the Android Head unit itself. If it doesn't deliver good output at pre-outs, no point in investing in external gear. Today you pretty much forced to choose - either good sound or an Android Head Unit. This is what we're trying to remedy, while keeping the cost in the lower brackets.
iceblue1980 said:
But then I would go back to the point 1 I made - the bottleneck is the Android Head unit itself.
Click to expand...
Click to collapse
That has nothing to do with the choice of amp (internal or external) you use. The output of the RCA's is the same input for either amp. It is simply delivered internally to the internal amp and through RCA's for the external. If it is not clean audio from the RCA's then it also won't be for the internal amp. The only difference is that the internal amp is cheap and under powered so it can't emphasize the crappy audio as well as a cleaner and more powerful external amp can
Internal amps are crappy.... always have been... and with the cheap price of external amps these days and the large selection of them, it doesn't make sense to upgrade an internal
And with that, I go back to my original point.... modding and improving a cheap head unit is not worth it. You are better off starting with a good quality base model first.
This particular head unit is clearly a sub par unit with bad sound quality, low screen resolution, and insufficient memory, so all of that would have to be fixed first before anybody worries about an output amp to begin with.
The long and short of it is that the OP is going to be spending probably twice as much as the head unit is worth trying to make it into what he wants.
Bob_Sanders said:
That has nothing to do with the choice of amp (internal or external) you use. The output of the RCA's is the same input for either amp. It is simply delivered internally to the internal amp and through RCA's for the external. If it is not clean audio from the RCA's then it also won't be for the internal amp. The only difference is that the internal amp is cheap and under powered so it can't emphasize the crappy audio as well as a cleaner and more powerful external amp can
Internal amps are crappy.... always have been... and with the cheap price of external amps these days and the large selection of them, it doesn't make sense to upgrade an internal...
Click to expand...
Click to collapse
I have to respectfully disagree. In these units, there is little to no correlation of the sound output between the internal amp and RCA's. This is why there are 2 different directions that modders take - one focused on the internal amp and one focused on the RCA output. Both mods cannot exist in the same unit by the way.
The RCA's have poor electronics behind them as well as poor shielding, resulting in the equally poor audio output. What you will be amplifying is just that - poor sound.
Bob_Sanders said:
And with that, I go back to my original point.... modding and improving a cheap head unit is not worth it. You are better off starting with a good quality base model first.
Click to expand...
Click to collapse
I would agree to a point but many "hi-end" android head units are very difficult if not impossible to mod and it's also a matter of price. As this is a charity project, we're looking to keep the cost low while maximizing the value.
Bob_Sanders said:
This particular head unit is clearly a sub par unit with bad sound quality, low screen resolution, and insufficient memory, so all of that would have to be fixed first before anybody worries about an output amp to begin with.
Click to expand...
Click to collapse
Yes many of these units are honestly not worth touching. As for CPU and memory - the use of these can be considerably optimized with Android programming skills, making them very much usable in day-to-day scenarios. As an example, you can check out the video in my signature and fast forward to where we show the Google Maps loading times on a 1Gb RAM unit.
Bob_Sanders said:
The long and short of it is that the OP is going to be spending probably twice as much as the head unit is worth trying to make it into what he wants.
Click to expand...
Click to collapse
This is probably true. But then again, he as many others are always faced with a choice of what to prioritize: sound quality or a fully-fledged Android onboard computer.
Finally, I think anyone can improve their head units if they would really want to as there is so much information out there and guides. It would cost time but not much money. This is, I guess, why XDA also exists - for everyone to share knowledge
iceblue1980 said:
I have to respectfully disagree. In these units, there is little to no correlation of the sound output between the internal amp and RCA's. This is why there are 2 different directions that modders take - one focused on the internal amp and one focused on the RCA output. Both mods cannot exist in the same unit by the way.
Click to expand...
Click to collapse
Yes there are.
The output from the fm chip (just for example) does not have separate outputs for rca and internal. It has only one (L&R) output set which is fed to an input selector which is in turn fed to a preamp. That preamp output is fed to the internal amp with what basically amounts to a tap off to the rca's. Aside from a few decoupling caps and such, along with a filter and output set for the sub, the RCA signal is virtually the same as what is being fed to the internal amps.
"poor shielding" amounts to a crappy set of rca output cables which can be replaced for a couple of bucks if you have shielding issues.
BOTH the internal and external amps get their signal from the same preamp and filter stages. Not only that, but the internal amp also gets its power from the same internal power supply as the rest of the head unit does, so if that power supply is not clean then it affects the internal amp too. Drive any power supply too hard then you start getting dirty sound. An external amp has it's own dedicated power supply, which means you don't have to drive the head unit's power supply very hard at any time. That leads to a cooler running head unit with lots of power to run its other components.
Internal amps are IMO... a crappy way to go.
I would agree to a point but many "hi-end" android head units are very difficult if not impossible to mod and it's also a matter of price. As this is a charity project, we're looking to keep the cost low while maximizing the value.
Click to expand...
Click to collapse
Well... you mention "charity" not the OP, but the point is that the cost is NOT low when you start talking about having to purchase higher res screens (complete with driver), new memory and dsp boards. Your pretty much replacing more than half of the head unit's essential electronics. Heck... if you're going to be replacing that much.... you may as well start from scratch and build one from the ground , up
Bob_Sanders said:
Yes there are.
The output from the fm chip (just for example) does not have separate outputs for rca and internal. It has only one (L&R) output set which is fed to an input selector which is in turn fed to a preamp. That preamp output is fed to the internal amp with what basically amounts to a tap off to the rca's. Aside from a few decoupling caps and such, along with a filter and output set for the sub, the RCA signal is virtually the same as what is being fed to the internal amps.
"poor shielding" amounts to a crappy set of rca output cables which can be replaced for a couple of bucks if you have shielding issues.
BOTH the internal and external amps get their signal from the same preamp and filter stages. Not only that, but the internal amp also gets its power from the same internal power supply as the rest of the head unit does, so if that power supply is not clean then it affects the internal amp too. Drive any power supply too hard then you start getting dirty sound. An external amp has it's own dedicated power supply, which means you don't have to drive the head unit's power supply very hard at any time. That leads to a cooler running head unit with lots of power to run its other components.
Internal amps are IMO... a crappy way to go.
Click to expand...
Click to collapse
Ah, I see now what you're trying to say. Okay so yes, you are correct on a number of points, however, as I mentioned before - we are driving the internal amp with a separate 18v 15A power supply (we only need 10A but there you go). A power supply that is custom-built using a step-up DC-DC converter with temperature-controlled cooling (at 8A+ it starts to get pretty warm).
The internal amp is completely disconnected from the internal 12V power, while still being connected to everything else. We improved the audio output quality by quite a staggering 40%.
Internal amps will never be able to compete with external equivalents, but when you put it in a perspective of an Android - it's a totally different comparison. Like comparing cars with trains. Sure, both are means of transportations but quite different in themselves.
By the way, the "RCA" mod actually removes the internal amp altogether from the circuit.
I will agree that 200 true Watts is probably enough for most people -If they also have a powered sub. Check the recommend amps for popular subs like alpine and JL. Deep bass require some muscle. And 200W feeding a sub, two (mid)woofers + two tweeters ain't much. Heck my woofers sounds notably better @2x150W compared with 2x75W.
Most modern car subs are mostly optimized for low frequency production in small boxes. This is achieved with a stiff suspension and big motors. -Not a very efficient in therms of db/W.
I also think your definition of true watts is quite different than mine...
In my book true watts means continuous 20-20khz 1% THD.
I just checked the 7850 specs, and it is actually quite impressive for it's size. With 18V input it delivers almost 90W. BUT at 30W the distortions increases and at 40W it skyrockets!
Regardless of budget I don't think many "audiophiles" would appreciate >10% distortion...
For a budget android car hifi experience I believe HU, USB DAC + external amp would be the way to go.
IMHO Viper is by far the best sound mod app but it can't replace a DAC. Does Viper have auto tune? Automatic input selection ? Autoand programable turn on/off?Hardware volume control? Ground isolation? Logic 7 centerchannel? Fully costume covers?
Viper and a standalone DSP is two rather different things.
My DSP also have high level inputs so maybe I should try if the 7850 output vs the preamp RCAs. You do seem to know the HU's internals quite well. Can you explain why internal amp sounds better compared to the preamp output?
Isn't the 7850 recurving same signal as the preamp plugs?
Allan_Hun said:
I will agree that 200 true Watts is probably enough for most people -If they also have a powered sub. Check the recommend amps for popular subs like alpine and JL. Deep bass require some muscle. And 200W feeding a sub, two (mid)woofers + two tweeters ain't much. Heck my woofers sounds notably better @2x150W compared with 2x75W.
Most modern car subs are mostly optimized for low frequency production in small boxes. This is achieved with a stiff suspension and big motors. -Not a very efficient in therms of db/W.
I also think your definition of true watts is quite different than mine...
In my book true watts means continuous 20-20khz 1% THD.
I just checked the 7850 specs, and it is actually quite impressive for it's size. With 18V input it delivers almost 90W. BUT at 30W the distortions increases and at 40W it skyrockets!
Regardless of budget I don't think many "audiophiles" would appreciate >10% distortion...
For a budget android car hifi experience I believe HU, USB DAC + external amp would be the way to go.
IMHO Viper is by far the best sound mod app but it can't replace a DAC. Does Viper have auto tune? Automatic input selection ? Autoand programable turn on/off?Hardware volume control? Ground isolation? Logic 7 centerchannel? Fully costume covers?
Viper and a standalone DSP is two rather different things.
My DSP also have high level inputs so maybe I should try if the 7850 output vs the preamp RCAs. You do seem to know the HU's internals quite well. Can you explain why internal amp sounds better compared to the preamp output?
Isn't the 7850 recurving same signal as the preamp plugs?
Click to expand...
Click to collapse
You're absolutely correct. While this unit will drive some of the passive subs (thanks to all the additional cooling), we do highly recommend using an active subwoofer for the best sound experience. Even an underseat sub like Kenwood KSC-SW11will make enough of an impact as many people don't want to use the extra space for a sub.
You're absolutely correct on the distortion part. I haven't experienced it driving 4 Ohm speakers in various cars but all of them had active subs.
On USB DACs - totally correct. However these head units have fairly unreliable internal electronics to effectively drive them (surprise surprise). Hardware modding is required and we haven't been able to get any good results. The internal hardware is too weak to drive DAC's. Drivers are unstable as well. External DAC's was one of the first things we tried.
As for internal vs RCA output - what you're mentioning is correct when it comes to most devices out there. This is how it should be. On these head units however, it's a bit of a mess. In fact, we tried to "rewire" it internally but it resulted in an even worse output from RCA's.
The internal electronics are many times completely removed and we install an internal preamp microchip with separate power supply (step down DC-DC converter) and redo the capacitance as well as internal shielding.
We haven't had any requests yet for RCA-only projects so it's still very much an area of testing and development for us.
My DSP is connected through usb and it works fine with USB audio player pro. For anything else I use the optical output. Do you think the speaker output would improve the soundquality compared to the optical output?
Also tried a I had a 8227L I also tried a E1DA 9038D DAC and it worked except I could not control the volume, so it would play at full volume. So I guess a DAC with a volume dial could work.
Your statement about only needing 10A at 18V don't match your claim about 200 true watts. The 7850 is class AB so efficiency is probably about 75% . 10x18x0.75=135W...

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