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VW Discover Pro flat output?

44K views 78 replies 21 participants last post by  2226cc  
#1 ·
Hi all.

Not sure how many people can answer this question but there are not too many other places that understand the question.

Basically, I am in the UK and have ordered a new VW Arteon that comes with the Discover Pro entertainment system.
I intend to fit my Helix P-Six DSP/amp with door components and a rear sub(s) driven from a separate amp.

Main source will likely be a media player through USB audio into the P-Six thus avoiding the factory system entirely but, does anybody know if the VW head unit has a flat outout and/or can be configured for low level out etc.
If it can I might look to simply using the factory head unit and avoid the clunky ish looking external player and Helix URC.3 control.

I appreciate the UK spec head unit could be different but thought it worth an ask at least.

Thanks.
 
#2 ·
Super interested in this. Have the same car with MIB2 fitted and I'm going to fit an external DSP as well.
Right now I'm using an ms8 with factory speakers but the sound is nowhere near where I want to.

AFAIK there is some kind of distortion after 3/4 of volume. I would love to measure it somehow and understand if it's flat or even if there is a loudness curve to take advantage of it and use it as it should (keep the same factory reference levels).
 
#3 ·
Most of the older VW's can be programmed with Vagcom for a flat, fullrange signal. I don't know if yours falls into that category, since it's new, but it should be easy enough to find out. Pika's statement about distortion is definetely true of the older head units, the OEM head unit in mine would distort badly at just over half volume.
 
#4 ·
In my case (Tiguan 2019 Discover Pro, NO DYNAUDIO) I connected VW head unit to Helix DSP III by High Level imput. The are distorsions in low-level frequencies, the lowest playable frequency is about 110 Hz. I’ve checked twice whole instalation - the problem is with VW HU(quality of the outputs). I’m going to buy a Helix USB Extension Card to stream directly to DSP from my phone.


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#5 ·
This sounds about right. The rear speaker wires should carry lower frequencies, but still won't be fullrange, and you still have the distortion issue. If Vagcom works for the new models it'll help a lot, but you'll still need to set your gains in a way that you max out your volume before the head unit starts to distort.
 
#6 ·
That's really wierd.
Its this your head unit?
Image


I don't hear any distortion in my case; I do have distortion above 3/4 of the full volume in my head unit so I've set my gains in the DSP to be loud enough when I'm hearing at 50% of volume. The trade-off is some background hiss, but it's ok.
 
#7 ·
Quick update on this, the output between the front and rear channels are definitely different; rear channels have less bass and a lot more midrange. Mixing both together also doesn't sound like the perfect solution. One thing that helps is messing with the equalizer: cutting bass to around -6 and increasing midrange a bit sounds a little better but to be honest the best option would be to somehow disable this stupid feature.

I've looked into getting optical out of the most150 bus and there is only one company that has this product and is charging a lot of money for it; also, there are no guarantees that the output via optical will be flat...

Suggestions?
 
#8 ·
Quick update on this, the output between the front and rear channels are definitely different; rear channels have less bass and a lot more midrange. Mixing both together also doesn't sound like the perfect solution. One thing that helps is messing with the equalizer: cutting bass to around -6 and increasing midrange a bit sounds a little better but to be honest the best option would be to somehow disable this stupid feature.

I've looked into getting optical out of the most150 bus and there is only one company that has this product and is charging a lot of money for it; also, there are no guarantees that the output via optical will be flat...

Suggestions?
It's still some months away until I get my Arteon, so I can't play with anything right now, although what you have found with the outputs doesn't surprise me at all.
Bit of a shame if you can't simply change it using VCDS (as you can in some Fords using the relevant software)

Does the Arteon use MOST as a Bus protocol? I can only find information on the Golf 7 that says it does.

If it does then like you say a converter may be a good solution. The Helix SDMI25 seems to be a good option but pricey and there is nothing anywhere that says where in the chain the factory stereo signal is manipulated. Would be a bummer to spend the money on an interface only to find it is still messed with.

All we want is a flat output signal - shouldn't be so hard Mr and Mrs vehicle manufacturers … :rolleyes:
 
#9 ·
Twonks

Tomorrow maybe I will have some time to desribe my „war” with VW high-level signal in my 2019 Tiguan. But now in short - it’s pointless to seek a quality in VW headunit due to distortions and missings in bandwidth. They are three options with optical connection - I will describe them tomorrow when I get back to home.


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#10 ·
OK

My setup : Helix A4, Brax x1000, Helix DSP III with director, Brax Matrix Speakers 1.1 2.1 6.1 (1.1 and 2.1 with Brax crossover, 6.1 active), sub Brax 10.1 active. VW Tig 2019 NO DynAudio.

At the moment the source is the VW head unit (Discover Pro) connected to DSP by high-level input. From the beginning there were a lot of problems with distortions. I checked the whole installation twice – also each amp was checked by specialist (damaged RCA output etc.). The gains of the amps are corrected with an oscilloscope. Diagnose – everything is OK!. The hole equipment is located in a trunk, also car battery. So you can see that the possibility to “catch” distortions from the car (electric installation, fuel pump etc.) is reduced to minimum ( I’ve also tried to “hang” RCA cables from the DSP under the roof lining :D )

As my predecessors wrote – they are big differences in a signal from VW HU. Each channel has DIFFERENT frequency response. The best (main flat) signal I get from left front. But it’s still ****ty. The difference in a signal response is +/- 8 dB !!! The most corrupted bandwidth is 56-140 Hz, the less corrupted is midrange bandwidth but still ****ty. Only from about 3-4 kHz I’ve got almost flat line. But the most interesting thing – VW HU DOSNT PRODUCE ANYTHING below 55 Hz. My sub is reduced to minimum at the moment – is the only way to don’t damage it. Mixing the gains from other channels to play 55-140 Hz bandwidth is a suicide. But still during the listening, our lovely VW HU can add an extra noise. I don’t know how to describe it exactly – there’s a big “bump” during the low frequencies. The “bump” has a much higher voice than played music (as high as crossover is setted), is “empty” or sth. Also mid tones are mainly reduced to minimum (by VW of course). Interesting thing that on each VW volume level the distortions take different shapes. The most interesting thing is that when you turn off your car and turn on it again, the distortions on a the same music level of VW head unit are DIFFERENT  When I saw this video
I was thinking I got it! I played a pink noise (all crossovers and filters were set to “0”) and started to modify an output gain of each channel. I have to admit that I thought that only gain level I can change on the DSP front panel :/ But after bringing the signal to more or less flat – there was a big big big smile on my face, the whole system sounds like it should be – the pure reference. The mids, the kicks, the gentle sub in the shadow….. achhh. But the next day everything was like before – almost no mids and lots of distortions in the sub freq. Moreover, I had to set on the director sub level almost to the max, increased the volume to the max for 5-7 second and after that the sub and mids frequencies were started to play. Then I started to seeking out what’s the problem and the results are written above.
 
#11 · (Edited)
The perfect solution? OPTICAL CONNECTION!

BUT :D:D:D

The whole VW system is based on a MOST 150. It’s an encrypted interface. Almost year ago I wrote to the Mobridge company if they plan to release MOST 150 interface. They wrote me back that it’s difficult problem and the whole operations will cost about 500 000 $. For them is uneconomical expense. Also Audiotec Fisher wrote me similar answer, they say “maybe”. For now

I see that the only MOST 150 interface allowing get digital output from the VW HU is NAV-TV ZEN V. It costs 749$ - in my opinion it’s so much overpriced. You get an interface and also 12 channel DSP. I don’t know what DAC is inside, I think it’s not a good one if they recommend connect their interface to another DSP  The digital output is “by them” 24bit/ 48kHz, the frequency response (also in analog) 18 Hz – 24 kHz. If the digital may be correct, but analog? I’ve got a lack under 56 HZ in my unit. SO HOW analog 18-56 Hz is possible by them interface? Magic?

Second option is to create a custom digital output from the VW HU. I sought advice in my country form a man who collaborated with FOCAL as designer of their unreleased DSP, winner of European Car audio awards, owner of a car-audio equipment repair / workshop, in short in our community – GENIUS. He made a lot of optical outs from aftermarket Alpine/Kenwood/Clarion etc. units and of course from factory ones. That’s what he said:
  • Just because the VW HU accepts the FLAC and other loosely files does not mean that it outputs it. 
  • If he manage to get out optical signal ( that’s not sure it will be minimum 16/44), there can be digital noise when the music is not playing. I can compare to the “noise gate” – everyone who plays electric guitar know what I mean. In fabrical units the “noise gate” is located after the part responsible to convert digital to analog. When we want to get out the signal from the VW HU, we get out the signal before the noise gate. And of course noise gate is designed to works with analog only.
Everything is possible, but the costs.
In my country getting the optical out from the aftermarket unit is about 100 $ because in an easy procedure, in VW HU the cost started from the 300 $ + due to unpredictable compilations. And in the end it can be output without minimum 16/44 :/

It’s possible to do, the Russian did it

? I²S to S/PDIF transmitter (V1.1) — DRIVE2
? I²S to S/PDIF transmitter (V2.0) — DRIVE2

When you check this guy Youtube channel you can see similar (Skoda) Hu is working with his toslink output, but he doesn’t show how the HU reacts when the music is stopped (noises?) I don’t speak Russian to translate it fluently, so I don’t know what exactly is the output quality and the price.

Third option is an airport express converted to USB power supply. It has digital output (16/44). It’s make a wifi in your car, you stream a lossless music to it directly via Airplay. Disadvantages – it starts about 50s, and if you have got Iphone connected to HU via carplay (view of Music app/ Tidal etc. on HU and of course steering wheel buttons works) and you switch on phone to “airplay” you cannot see what’s playing on a VW HU and cannot control the phone by a car interface.

Fourth option

Buy Audison Bit Play or similar and android interface
. This allows you to stream music by optical output form Audison to DSP and control everything by the android app. I don’t know if android video interface works with a steering wheels buttons.

Fifth option

Buy an external DAP player (Ibasso, Fioo etc.) and connect it to the DSP by COAX. You should buy the cheapest dap because you will use it only as a transport, the DSP DAC will do the job.

Sixth option (my option  )

Today I ordered Helix USB Extension Card for my DSP. I will connect my Iphone directly to the DSP by USB cable. It’s 192kHz/32 bit. My processor supports less, but I can always move an extension card to another better helix/brax DSP or sold it without difficulties. Disadvantage is that the USB cable cannot charge your phone (you have to use Apple Camera Connection Kit 3). It will cost 150 $ + Apple adapter and USB cable. Iphone is much faster than a DAP player.

If somebody have some informations about getting a digital output from VAG group MOST 150 interface please share.

Sorry for mistakes in writing, english is not my first language.
 
#18 ·
I had the first BT volume controller in your list and it worked sort of ok.

One issue for me was the ipod touch I use for music doesn't have too many steps between volume adjustments so I could never get it to the right volume level, and it fell to bits after 2 months, so I went back to the URC.3

A lot of food for thought in this thread now though, so thank you all for that :D
 
#19 ·
For those with the premium sound system (DynAudio / Fender) on MIB2

VAGCOM / OBD11:
  • I'm curious to know if starting off with the premium system and then bypassing it with VAGCOM / OBD11 gives you a flat full range signal via line out?
ZEN-V:
  • The whole "MOST" system thing is new to me ... but it's a digital signal / fiber input AND output ... so technically it should be simple data transmission and should sound great so long as you keep the signal digital right??
  • My car has the fender amp under the drivers seat, it's a 2019 GTI SE w/ fender system. I believe that makes me MIB2.
  • I don't know which unit in the factory chain does the processing, but the ZEN replaces the factory amplifier entirely. So if it's a clean, full range, digital signal all the way up to the factory amplifier, and then the "fender amp" in this case does the processing, then the ZEN would probably be fine because it replaces the factory amp.
I'd be surprised with a platform as common as ours that we are not the pioneers of this information and these various scenarios have been answered already in the industry?
 
#20 ·
I mean it definitely reads like you can flatten it out by long coding (VAGCOM / OBD 11 stuff)

262383


I'm inferring here that long coding 00 values in those respective bytes = flat response. I didn't catch a reference to the Control Unit or Adaptation where you would adjust these bytes in the ZEN manual though.

I'm also inferring that this means the equalization is adjusted prior to reaching the ZEN. But those bytes might be specific to the MOST150 output.

So if you want a flat response on direct line out from the stereo it might be located in other bytes.

I don't know though.
 
#21 ·
Ok I'm back again but don't know if anyone's reading this :(

There are two manuals.
  1. "Installation Manual"
  2. "Download Manual"
when you click on the button that says "Download Manual" it shows you exactly how to code the NAV TV in VAGCOM (and therefore, obd11). I thought "download manual" just meant - download the other manual on the same page called "installation manual" :p

Per the quote in the screenshot above, again, i'm assuming here that by coding as the instructions show, this is how you achieve a flat frequency response. But, some of the codes in the "Download Manual" manual might be too many extra to code in because it's also meant to supplement putting the ZEN in entirely.
 
#23 ·
Hey guys,

I feel that we shouldn't give up on this. I'm currently using the high-level output of my discovery unit. I've measured the output of them and obviously found that they are not flat at all, no matter the input you use (tested android app and Bluetooth).

266018


This is the output curve closest to the flat that I got. bass is set to -6. mid and tweeter to 0.
Foundings are that there is a clear high pass filter set around 70 Hz.
There is also a variable loudness filter based on the volume. this is actually something that we could take advantage of, we just need to be sure that it is aligned with the output of the amps. As a reference, around half the volume, it disappears.

The loudness curve only affects lower frequencies, below 200hz.

266019


Measured distortion. to be honest, I don't know how to interpret this, but I'll include it just in case someone here does.

So clearly not the best source, but I still believe it's not the worst either.
I've read somewhere that MIB1 older units were able to output low-level signals trough the speaker output; anyone tried to see if that's possible with these newer units?

Also, very interested in what @01LSi discovered in navtv documentation. any clue if that will change the high-level outputs as well?

@podwodnykot good point as well; if we enable the Dynaudio option in mib2, what happens to regular high-level outputs ? do we have any signal at all?

I'm sure there will be a way to get this! My DSP also has Bluetooth, analog and optical inputs but I want to have MIB controlling everything.
 
#24 ·
@podwodnykot If you want I can measure the head unit by channel, to understand if it's different. The way I'm doing this is connecting the high-level output of the head-unit to my DSP and then route 2 channels with full range / no processing whatsoever to 2 low-level outputs (RCA). From there, I have an external soundcard that I use to capture the signal to my laptop and use REW to see what's going on. I had some measurements of the head unit using different volumes where you could clearly see the loudness curve being applied differently but I don't know where I save that file. I can get them again if you guys feel that is useful and would do it by channel FL FR RL RR.

Btw, I think that the rear channels have a higher high-pass filter than the front ones. I've measured it as well and the signal was completely different from the front channels. Since I have the setup to measure the output on my end, I can try different suggestions that you guys might have; i think the only thing that I'm missing is a way do code vagcom.
 
#25 ·
Last post, I promise. I've also tried to contact the Russian guy that gets optical output from every unit (the one with the youtube channel). He said that he never has done one of these units so he needed a picture of the brains of the main head unit to understand what could be done. I'm almost sure you can get I2S signal somewhere in the mainboard, I'm just not sure if the signal will be flat. Ideally this would be my last option.
 
#26 ·
Thanks and good work Pika.

I can't add anything to the thread until I get my new car, which with the current situation could well be some time after the planned July delivery!

If I see / hear anything between now and then, I'll post here but feel this is the best place for information with the collective minds that are available.