yashsingh1/xdaforums huggingface dataset:
[MTCD Hardware Development] patcher2k:
I have spend a bit more time to find out how the input switching it's made.

1. modify the miniDSP board to operate in proper i2c mode no SELFBOOT (remove EEProm, pull Pin6 of ADAU1701 to GND)

2. I connect a I2C-Logger to the bus to find out what happened while changing the input. I have seen, that at startup a device with address 0x46 is probed but its not there. After seeing this I program an Arduino to act as an I2C slave on address 0x46. Now I can see that this dev is written if the source is changed. But the values are all 0x00. I analyzed the mcu firmware and found out that the device 0x46 is an SGM6510 audio switch.

The question now is, why the values are all 0x00. In the disassembly of the write function is a condition. If it's false 0x00 is written otherwise the wanted source is written.

At the moment I have no idea what this condition is. Maybe there is somebody who has also analyzed the firmware and knows the mechanism.

Help is welcome.... ;)
[MTCD Hardware Development] patcher2k:
Short update...

Yesterday I have checked if the code for the SGM6510 is also present in older MCU firmwares. I analyzed the the version MCU KLD 2.80 and as I expected there is no code for the switch.

In my device I use the version MCU KLD 2.94e. (with the SGM6510 code)

Is there anybody out there who has also analyzed this firmware?
[MTCD Hardware Development] sev:
does this mod, at all, improve a2dp and remove upper frequency distortions?
[MTCD Hardware Development] marchnz:
No. Poor a2dp is a feature of all MTCB/D/E.
[MTCD Hardware Development] sev:
it doesnt have to be! this community has solved so many problems, why cant we solve poor a2dp!?
[MTCD Hardware Development] chrismis:
Hi All, know somebody where do I get this board: KJD-DSP1701-V3
[MTCD Hardware Development] tomknezic:
Is this tested for Android 5.1 devices with 1GB RAM?
[MTCD Hardware Development] sev:
after some searching I found the actual DSP units installed from the factory on these units on sale by themselves. About $35 usd. Plug and play

https://www.aliexpress.com/item/DSP...000&pvid=b8269ff7-1aeb-4679-9e26-a039f6913be9
[MTCD Hardware Development] BlueChris:
I bought it in a rush for an easy upgrade but I don't think in my unit i have the plug for it now that i see a photo of Myne.
[MTCD Hardware Development] SilentO:
Any updates? Does it work? Do you have any pictures?
[MTCD Hardware Development] patcher2k:
I got it working... :D

I have made a small pcb which fits on the not mounted connector on the mainboard.

The sources (BT,FM,DVD,AUX) are controlled by two mcu GPIOS. (Pin 83 and 85)
[MTCD Hardware Development] lpnb12:
Thats very cool. would love some more information if you have time.

did you make rhe board? also my Xtrons PX5 does not have the place for it.

I only need FM and DVD because my unit has A2DP that must be digital processed by android.

:good:
[MTCD Hardware Development] Octane70:
Could you share the part# of the dsp unit you purchased and possibly where you purchased in t from?. Was also wandering if the dsp unit gets rid of the "static noise" that could be heard when there was no music played with the volume up that has plagues these units.
[MTCD Hardware Development] patcher2k:
Hi,

I designed the board with KiCad. Then, I have ordered the pcb's from JLCPcb.

[MENTION=7879500]lpnb12[/MENTION]

The source selection is controlled by the MCU. I have only analyzed the KLD firmware and there are 3 GPIOs which are used to select the analog source.

If the current audio source is a signal which comes from the PX3/PX5 the MCU select the digital input of the dsp.

[MENTION=3388974]Octane70[/MENTION]

The dsp is a ADAU1701JSTZ ordered from Aliexpress.

The "Static Noise" issue is much better because the dsp has a better dac inside.
[MTCD Hardware Development] lpnb12:
Are you interested in sharing your design or selling the board?
[MTCD Hardware Development] jun81:
Am keen too!
[MTCD Hardware Development] mahtew:
since you managed to do so much, maybe you will consider one more upgrade: D?

I have asked sellers on Aliexpress few times about the possibility of adding spdif-out to their HU - a negative or evasive answer each time.

Dasaita has a new design for SOM board with built-in DSP for PX6 (they already sell it on ALIEXPRESS, photos found on 4pda RU). but 'a' designers forgot to add SPDIF :). according to them (sellers from Ali) SPDIF does not really matter ... of course until You start using external DSP and amplifier.

** btw. PX6 supports USB3.0, but its also missing: D **

RCA to SPDIF converter can be used, but it is completely pointless due to losses in sound quality.

I started to look on my own for schemes, chips ... but I'm a construction engineer, so I do not quite understand what I'm looking at, and even if I'd found something, the proper design would take half of my life: D

since your design is quite cool, maybe there can be room for improvements ;D for example a simple solution to add spdif OUT that would send a signal to an external DSP.

iS it possible to steal digital out from ADAU dsp and then a Digital -> SPDIF converter (TI DIX4192-Q1?). Probably the problem would be to add volume control by spdif (but JOying made that happen in their new HU). simplified application diagram can be found on TI website.

also would it be possible to change adau dsp for one with better SNR like ADAU1463?

what do You ppl think about that? is it possible tomake it work?
[MTCD Hardware Development] patcher2k:
Hi,

if I remember correctly the processed signal is available as I2S signal on the digital output pins of the dsp. So it should be easy to add an I2S to SPDIF converter to get a standard SPDIF signal. (including volume control)

A chip which can do this is the Wolfson WM8804G.
[MTCD Hardware Development] mahtew:
so this should be as easy as:

buy: Audiophonics Digipi+

connect i2s; plug power .... and ready to go?

there are 8GPIO pins. but isn't this should be somehow set in DSP to push i2s data through this pins?
[MTCD Hardware Development] brickbeats:
Hello All, I'm going to attempt this mod to a Intel Sofia 3GR unit soon, is there any hints or tips that will help me succeed at this mod that anyone can offer? Thanks in advance.
[MTCD Hardware Development] lpnb12:
Also, did you employ an analog audio switcher? I removed the existing switcher/dsp, i removed that chip as per the original instruction but maybe it can be left and just the switcher part for analog? (may be not...)

---------- Post added at 08:11 AM ---------- Previous post was at 08:06 AM ----------

Good luck.... If it is a similar design to these other should not be a problem. Mine (xtrons) had different placing of some of the resistors and used different pins on the existing dsp so FM radio is using a different pin i think cause my fm no londer works. I ma going to have to trace back to the FM circuit and see what is used. Oh yeah make sure you have a soldering iron with a really fine tip and if you're an old fellow like me you'll need a magnifying glass. [emoji849][emoji368]
[MTCD Hardware Development] patcher2k:
[MENTION=7879500]lpnb12[/MENTION]

On my board I have used a CD4052 for the analog port switching. (16 Pin IC) Please post a picture of your device.

If you keep the BD37xxx in, it will have unknown side effects. The firmware checks if a dsp is present. If it is found the BD37xxx will not be initialized.
[MTCD Hardware Development] patcher2k:
I have attached the schematic of my board. Maybe it will help someone.
[MTCD Hardware Development] lpnb12:
Thanks very much!! I don't know if I will have time but maybe I will try to reproduce your design! or someone else will!
[MTCD Hardware Development] kavatzoulas:
i am interesting about the spdif/optical output if its possible to have ( i dont care about the dsp option because i ve already have an external dsp unit Helix ) and second thought the HDMI pin outs is it possible to use them? it would be perfect because all the signals radio, navigator, music, video could pass from the hdmi output
[MTCD Hardware Development] kaise123:
The scheatic is definitely helpful - But is there any chance you can share your board layout (The actual KiCad files you used) so that others are able to get a similar board made up? My main board has an identical layout to yours, so I would be interested in getting some of these PCBs made myself.

If not, do you plan on selling them at all?
[MTCD Hardware Development] puudub:
I am attempting this update when I get my HU back from china, have the rest.

Wouldn't recommend sending electronics back to china, as the customs are crazy there.

I have an external amp, so I'd rather skip everything in HU and run RCAs straight from DSP.

Should I add capacitors?

And did I get pins right, markings on the board are confusing (fig.9 in OP, starting from top left)

pin2: FR

pin3: FL

pin4: RR

pin5: RL

And where should I add ground for audio?

Been lurking around in XDA since the birth of android, finally decided to make an account, hi everyone!
[MTCD Hardware Development] patcher2k:
Hi

I have attached the gerber files of my board. With this and the schematics the board can be replicated.

Who wants to build the board, can upload the zip file to jlcpcb and order the pcb for a low price.
[MTCD Hardware Development] kaise123:
Thanks! I will definitely look at getting some printed ?
[MTCD Hardware Development] jun81:
Thank you for sharing!

I have ordered the pcd to diy.

could you also share the size of the capacitors and resistors to order?
[MTCD Hardware Development] patcher2k:
Hi,

I have attached the bom of the board. The most parts have a 0402 footprint. The space on the board is limited. I have soldered by hand with hot-air and solder paste. I think this is the easiest way to do this.
[MTCD Hardware Development] jun81:
Cool! Thank you very much! Can’t wait to work on it!

can i check did you change any of the capacitors to others? for example 5n6. I can't seem to find them in the 0402 size
[MTCD Hardware Development] patcher2k:
Hi,

I have ordered the most parts from www.reichelt.de. It's a german distributor.

They have the 0402 5,6 nF.

https://www.reichelt.de/smd-kerko-0402-5-6nf-25v-10-mlcc-x7r-0402-ce-5-6n-p193962.html?&trstct=pos_0
[MTCD Hardware Development] stevey500:
This is awesome, adding the DSP processor after the fact. Breathes new life into a head unit that would otherwise just be replaced.

I have a px5 mtcd with DSP included. I see on the first page of this thread that some modded development of the amplifier apk happened. Does anyone know if it's possible to implement subwoofer delay? This is a function I wish I had. I really don't want to have to purchase a whole external DSP processor unit to get the factory subwoofer delay/distance back.
[MTCD Hardware Development] okim:
New version of eq app have possibility to set timers for all speakers and have few more options. I found it on malaysk ROM, but now I am using Hal9k Mod and I am looking for APK version of this app.
[MTCD Hardware Development] kavatzoulas:
have you found any solution? is it possible to buy and connect an i2s spdif converter (i found many for raspberry or standalone on aliexpress) so to have an spdif connection with my beloved Helix DSP?
[MTCD Hardware Development] mahtew:
yes and no

Currently I have MCU board without DSP and i'm waiting for new PX6 core + MAX6 MCU board (with dsp). i won't do anything with my current board (i will definitly breake it :D) till I get new one.

I was able to find and buy Adau1701 board with extension board SPDIF out. I also bought USBi burner for SIGMAstudio (but due to my later findings i think that it won't be necessary) because seller told me that some programing to ADAU willl be needed (to route signal from i2s and adc to mp10 pin).

i don't have osciloscope to check but in SIGMA STUDIO all hardware registers are ON by default and since ADAU1401 test boards from ali are default designs so MP10 pin might send i2s data OUT.

If that is true then adding spdif out is easy (little soldering and good to go).

If not then some programing to adau is needed (but 'analog devices' forum is very helpful, so it might be easy solution).

so you need to wait :D

some photos attached.
[MTCD Hardware Development] chrismis:
Sub channel control

Hi! Which Sub channel do you can control whit ES7144LV?
[MTCD Hardware Development] j3ffery77:
Is there anyone willing to make these mods to my existing PX5 head unit for a fee?
[MTCD Hardware Development] suebsss:
The sound is very rarely heard.

With noise when adjusting the volume> 25

I have to find a preamp to put in. Yes to solve the problem.

ADAU1401 output enough for a power amp? If it will connect to RCA

** I use google translate helper.
[MTCD Hardware Development] Jean-Mi2:
RCA

Hi !

I did the mod successfully and the sound is really better.

Congratulations and thanks for the job !
[MTCD Hardware Development] jerrymh:
whit this mod the hiss an pop sounds disappear?
[MTCD Hardware Development] jun81:
Have question for those who did the mods,

Probably sounds stupid,

I couldn’t get the exact resistors.

Like 475R i got 470R

7kR i got 6.8kR or 7.5kR

Will it be ok that i replace with these values?

Thank you
[MTCD Hardware Development] patcher2k:
Hi,

the 475R resistor is part of the PLL filter. Refer to the ADAU1701 datasheet the resistor can have a tolerance of 10%. So I think the 470R is ok.

The 7k resistors are part of the ADC input. The value depends of the input level. The value of 7k is used for an input level 0f 0.9V RMS. I think 7.5k is also ok.

Good luck...
[MTCD Hardware Development] suebsss:
I have put the preamp and it can be fixed;

But the sound from the RR RL no sound speaker(no preamp, adau1401 to tda7851);

ic tda7851 requires output from bd37033f pin 15 (mute) or not ? ;

output FR FL to preamp to RCA external poweramp ok

** i use google translate help
[MTCD Hardware Development] halloj:
Anyone who has a link to the real 15-band EQ of a modified MTCD/E head unit with a DSP inside?

Thanks.
[MTCD Hardware Development] Jean-Mi2:
Hi,

Know that the sound quality has been improved by adding this DSP/DAC, I want to have the best possible sound.

So, I tried several apps dedicated to Hi-Res audio files like PowerAmp, Musicolet or USB Audio Player Pro.

Despite an additional sound quality gain, these applications do not see the DAC installed. Therefore, it is impossible to exceed the limits of Android: 16 bits/44.4 kHz.

How to finally be able to enjoy a true high resolution 24bit/96kHz sound that the DAC ADAU1701 is able to produce ?
[MTCD Hardware Development] marchnz:
the MTCx DAC is controlled by the MCU.
[MTCD Hardware Development] Jean-Mi2:
Thanks but I understood that. I just want to know if it's possible for the audio player to interact with the DAC, perhaps with a modified MCU software ?

Or is it possible to increase the specs of android with a modded ROM ?
[MTCD Hardware Development] Jean-Mi2:
So, in the PX3 datasheet, it's noticed that its audio I2S interface supports up to 32bits and 192kHz.

But the ADAU board uses an 11.296MHz external clock from the CPU coreboard (I2S bit clock frequency for the sampling rate frequency of 44.1kHz).

So, I understand that the ADAU board is limited to 44.1kHz, which cannot be changed...

Am I right ?
[MTCD Hardware Development] suebsss:
data sheet page 38

These bits set the number of DSP instructions for every sample and the sample rate at which the ADAU1401

operates. At the default setting of 1×, there are 1024 instructions per audio sample. This setting should be

used with sample rates such as 48 kHz and 44.1 kHz.

At the 2× setting, the number of instructions per frame is halved to 512 and the ADCs and DACs nominally run

at a 96 kHz sample rate.

At the 4× setting, there are 256 instructions per cycle and the converters run at a 192 kHz sample rate.
[MTCD Hardware Development] brickbeats:
Left over parts from an attempt

I attempted this on an Intel Sofia Unit, and I was not successful due to not being able to find where to tap into the IC bus. I have the adau1701 board with the oscillator removed, the dsp for the sub and some other itmes for sale if anyone is interested. PM me, I'll post pics later
[MTCD Hardware Development] Jean-Mi2:
Thank you for the explanation.

How can I change this setting ?
[MTCD Hardware Development] marchnz:
Unless someone can modify the MCU code, you can't.

Use an external DSP.
[MTCD Hardware Development] suebsss:
adau1452

adau1452 + 32bit dac is used instead of adau1401 ?..
[MTCD Hardware Development] Beunhof:
Can I use a CS4344 instead of the ES7144LV? CS4344 boards are readily available for cheap. Might be worth trying.

Also I see no ground connection in the instructions?
[MTCD Hardware Development] suebsss:
I think using via adau1401 digital output to cs4344
[MTCD Hardware Development] Beunhof:
I can confirm the CS4344 boards work. This is a much cheaper and easier alternative to the ES7144LV IC because the RC circuitry is already on the board.

I think I wired everything the way OP described, but my front right and rear left are swapped for some reason. Can someone tell me which output on the DSP board corresponds with which speaker?

EDIT:

After some testing I figured out the right order:

OUT1 is FR

OUT2 is FL

OUT3 is RR

OUT4 is RL

So I swapped 1 and 4 and now everything is working like it should.
[MTCD Hardware Development] Mickygnt:
Hi, I decided to give this mod a try but my PX5 MTCE is a bit different, the audio chip is on the back of the board and is a ZL3560 not the BD37033

I assume I can still do the mod, has anyone else done it with this ZL3560?

And does anyone have a datasheet for the ZL3560 for pinouts?
[MTCD Hardware Development] suebsss:
i think pin ic is the same ZL3560 BD37033
[MTCD Hardware Development] Untzo:
dsp

Can i have the apk for that DSP app? Mine is really glitched
[MTCD Hardware Development] haxigi:
Hello. My HU is PX5 Android 9 with DSP based on TDA7851. I have connected HU via ISO cable, not RCA. Sound quality isn't bad, but neither good. Music from app, CD or even FM Radio sound so flat and raw. Playing with EQ doesn't change anything. My old BMW CD53 radio got much warmer and softer sound so is what i would like to achieve with this HU.

Why is that? Its hardware fault or MCU? Mine is based on MTCE_GS_3.17
[MTCD Hardware Development] suebsss:
Change the ic opamp to burbrown ic
[MTCD Hardware Development] marchnz:
What did reseller suggest if eq isn't working. Also, try q&a forum, this is for modding DSP.
[MTCD Hardware Development] Kera88:
Hey there. I'm on the way to put DSP as in first post on my PX3 XRC unit and like to ask or i have right. It's going about that four additional pins on coreboard, which doesn't have metal case, but I see 4 pins being not used. Can someone agree with me that 4 pins are to be used as output sound for DSP?
[MTCD Hardware Development] etulio:
Some sellers in Aliexpress are offering the MCU with the DSP already integrated at reasonable prices, I just bought this Dasaita one, for my HU Dasaita PX5 4Gb/32GB Android 8:

https://es.aliexpress.com/item/32965198383.html?spm=a219c.12010612.8148356.10.2f255e431gZFDw

There are cheaper alternatives for around 22€ (Just search Aliexpress), but I prefered the Dasaita above:
[MTCD Hardware Development] waloz:
MTCAmpsetup.apk

Hello everyone. I have a px3 7.1.2 unit, I also have DSP board. I only miss the 15 bands EQ app. where can I get this app ??
[MTCD Hardware Development] sda2:
The HCT-PX5-REV3 does not have an I2S output on the pin header. I had to solder directly to the Wolfson audio DAC for a signal.

Here are some pictures of the connections, it's working great!
[MTCD Hardware Development] brickbeats:
How did you figure out what pins to use? I have a sofia based radio and your sound chip looks like the one i have.
[MTCD Hardware Development] sda2:
I checked the datasheet for the four needed connections and traced the pins to better solderpoints :)
[MTCD Hardware Development] Konni_:
MTCE-XJH no Sound with DSP

Hello,

I have installed the ADAU Test Board, the DSP seems to be detected from the MCU, but the sound output didn't work correct.

On the RCA Line Outs I don't hear any sound (or it is tooo silent), if I connect a small 2W Speaker to the regular Speaker Outputs on the ISO Plug, I can hear the Sound, but only really silent (Unit is set to 30, wat is maximum), I can also control the Output Channels via the "Sound Applet" (I mean if i turn a output in the Applet under Gain to minimum, the speaker on this output is silent), so I think, the DSP is detected and working.

I have attached a Picture of my SoundProc Board.

[ 0.671018] --mtc @ audio detected dsp1 (0)

If I switch to the Radio App, I can hear also Radio very silent.

Could it be, that the MCU didn't turn on the Amplifier, or is the Output muted ?
[MTCD Hardware Development] Konni_:
After a little research, I have connected the OUT from the DSP Board directly to the Amplifier, the the Output does work, but not very loud.

I have the Audio Board examined there are 3 SGM8905 ICs, I think these should amplifi the output signal.
[MTCD Hardware Development] gwaitsi:
I've got an MTCE PX5 board with some audio issues when connected via ISO Quadlock but only low level white noise issues when connected one the bench PSU.

I want to add a DSP to the unit, but as has been mentioned in this, it has a ZL3560 on the underside of the board, please take a moment to check out this thread

https://xdaforums.com/android-auto/...eunavi-vw-px5-h-identification-sound-t4033271
[MTCD Hardware Development] Pacote-san:
Whats the most cost effective board I can buy to install on my Witson PX5 board?
[MTCD Hardware Development] Pacote-san:
This is my unit (witson PX5) with the px5 board unplugged.

Any ideia if its doable and what chip I need to buy? I really want to try it
[MTCD Hardware Development] pir8man:
Your unit, like mine... Has no pre-existing connection for a DSP board. So you would need:

DSP test board:

https://www.aliexpress.com/item/-/4000116925463.html?spm=a2g0s.8937460.0.0.745a2e0eVQULth

If you want separate SubWoofer output, you need an extra DAC pcb:

https://www.aliexpress.com/item/-/32958381857.html?spm=a2g0s.8937460.0.0.745a2e0eVQULth

If you want analog input switching (Radio, AUX, TV/DVD) get the analog switch chip:

https://www.aliexpress.com/item/-/4000119718264.html?spm=a2g0s.8937460.0.0.745a2e0eVQULth

You will probably want a Universal PCB to assist with assembly & connections.

Here is the one I plan on ordering: https://www.aliexpress.com/item/-/32923792538.html?spm=a2g0s.8937460.0.0.745a2e0eVQULth

... a bunch of 30AWG wire for connection points.

The only other thing I can find that is needed is an 100 Ohm resistor for MCLK
[MTCD Hardware Development] Pacote-san:
Thanks a LOT, when you install on yours can you post the diagrams I need to follow? I wasnt able to figure out the pinout yet.

As of right now I use the unit outputs RCAs': SUB, FR and FL to go straight to my amplifier.

So in order to be able to control the sub I need to buy the extra dac ? Or i can do it with the current RCA Im already using?

And what would be "analog input switching" ?

thanks again!
[MTCD Hardware Development] Pacote-san:
Also, my coreboard doesnt have the 4 extra pins, does anyone tried with that?

Edited:

Nevermind, I saw that [MENTION=1021010]sda2[/MENTION] soldered directly to the Wolfson audio DAC and its working :D
[MTCD Hardware Development] pir8man:
Fortunately, I need all 5/6: FR, FL, RR, RL, & SUB. If you can get RR & RL to act as a low pass filter for SUB is beyond my knowledge.

Analog input switching to switch between your non-digital sound sources to play through the DSP: Auxilary input, Radio, TV, or DAB. Because the DSP board only has one analog source input. If you do not add the switch, you have to hard wire only one analog source to the DSP. I use radio and my AUX input on occasion, so I want the switch chip for my install.