Assuming coupe!

If you have fade front to rear then the stereo isn't coded for Bose entirely correctly , hopefully it comes up BOSE when you turn it on?

Bose in a coupe is Front Channel only driving all 7 speakers

Fading to the rear will just turn all 7 speakers off!

The sound equalisation is preset and hence fade all to front , turn volume up and stick your head near a rear speaker you should hear something but it is meant to be "fill in" sound much lower volume than the front door main speakers.

In a roadster the rear is used to drive a central Sub woofer (8 speaker setup)

 

Hi WAK

Just been out and double checked and there is no noise at all from the rear speakers with the volume cranked up.

Yes it is the coupe and BOSE appears when the head unit is switched on.

 

Could be an amp failure or if it previously has aftermarket kit that's been removed

When owners de-mod a vehicle some are not as bothered when refitting things for a sale.

Needs further investigation sadly

 

Do your door cards have Bose on them?
If you had a non Bose car with a Bose coded headunit that may give you this situation but I don't know if Bose coding effects the line and speaker outs on the headunit

 

Do your door cards have Bose on them?
If you had a non Bose car with a Bose coded headunit that may give you this situation but I don't know if Bose coding effects the line and speaker outs on the headunit

No indication of which OEM headunit the OP has...
However all the pinouts of the Chorus II and Concert II that I have seen only ever have speaker outs labelled for front speakers; never the rears?
They do have a full set of front and rear line outs to drive an amp, but as we know the BOSE amp is front channels only (except Roadster as mentioned, where rear channels drive sub).
For this reason my assumption has always been that a non-BOSE setup either does not have rear speakers, or rears are driven in parallel from front speaker outs? Can anyone confirm?

 

For this reason my assumption has always been that a non-BOSE setup either does not have rear speakers, or rears are driven in parallel from front speaker outs? Can anyone confirm?

Hi pcbbc,I can confirm that on my non bose concert head unit,the rear speakers work independantly from the front when turned to"fader"

 

Hi pcbbc,I can confirm that on my non bose concert head unit,the rear speakers work independantly from the front when turned to"fader"

Thanks Les.

Strange then that the Concert II doesn't show the rears on the label (put I presume they are the "vacant" pins on either side of the fronts):

 

Strange then that the Concert II doesn't show the rears on the label (put I presume they are the "vacant" pins on either side of the fronts):

Hi,stole this from wak's site,pic clearly shows no pins for rear speakers,very odd. Don't know if chorus and concert are the same :?: the mystery goes on

 

Hi,stole this from wak's site,pic clearly shows no pins for rear speakers,very odd. Don't know if chorus and concert are the same :?:

Same. I had a Chorus.

the mystery goes on

According to this post headunit drives fronts and separate amp for rears.

Seems plausible, but surprised I've never heard this before. Mind you I have BOSE, so only really familiar with that setup.

 

On a non Bose/Chorus 2 (CD Changer + Cassette in my case), the rear speakers are driven from an amplifier under the rear seat. The 12 volts supply to the amp, and the audio signals get there via the CD Changer cable, that plugs into the Chorus, (LR, RR, 12V & COM, you can see them on the label photo shown in previous replys).
I just fitted a Bluetooth adapter to my Chorus, and initially had the same problem, no rear speaker output, which I eventually worked out, was down to the fact that I had not correctly fitted the adapter cable from the CD Changer cable loom to the CD Changer connector on the Chorus, hence the outputs from the Chorus never got to the rear amp etc.
The same situation will arise when an aftermarket head unit is fitted, unless you fit an adapter cable between the CD Changer loom and an output on the new head unit that will provide left and right speaker outputs signals, +12V and GND, suitable for the under seat amp. These must be specifically for the rear speakers in order that the head unit Front/Rear Fader works.
Failing such an output on your new head unit, you'd have to run new cables and power the speakers direct from the head unit rear speaker output, by-passing the amp. If you retain the amp, it'll need +12V and GND (COM), which you'd have to pick up from the head unit supply. The amp can only handle low signal levels, not speaker power outputs. High input levels will kill the amp.
Hope this helps someone, as it took me hours to work out last week!

 

This pic shows the rear speaker amplifier outputs on the Chorus, LR, RR, COM, 12V. The same connector has front speaker amp outputs, LF & RF. This may be for the Bose amp, but can't be sure, as mines non Bose.

 

This pic shows the rear speaker amplifier outputs on the Chorus, LR, RR, COM, 12V. The same connector has front speaker amp outputs, LF & RF. This may be for the Bose amp, but can't be sure, as mines non Bose.

Great information PlasticMac.

Yes, lineouts and switched power for BOSE.
Although note that in Coupé BOSE uses front line outs only, and while Roadster also uses rear line outs they drive sub only (as discussed previously).

 

You've made good points and makes sense

Non-Bose have an amp to drive rear speakers hence front only is needed for fronts
Rear line out is used for the amp (built into left rear speaker )

 

and the audio signals get there via the CD Changer cable

Hi, not wishing to muddy the water,but what if there is no CD changer fitted ? have I missed something ?

 

The CD Changer loom will be there anyway, because it doesn't just do the CD Changer function, but supports the rear speaker amp, which is always there. The loom supports options even if they are not fitted to your car.

 

The CD Changer loom will be there anyway, because it doesn't just do the CD Changer function, but supports the rear speaker amp, which is always there. The loom supports options even if they are not fitted to your car.

Hi,got you now, just had a look in the rear of mine and low and behold,there can just be seen the plug of a cd changer cable poking out from depths,might have to buy a changer now,mind you I only have 1 cd :lol:
well done that man.

 

Bose/non-Bose, with or without aftermarket head units, if we are being honest, all sound $hite.

I would like the time and inclination to strip out all the (almost 20 years old) junk and replace and rewire the whole thing.

My thing about originality would probably stop me.

Speaker technology has improved considerably, you don't need auto-changers and tapedecks, and it's nice to have hands-free calls and music streaming. (not that I would make or receive calls whilst driving; when I am driving, I drive)

Add to this the external amplifier(s), then the weight saving would be worthwhile.

It has been mentioned before, but the door card covers a quarter of the cone, when you remove the grille, so attention is required in this direction too.

Has anyone done this? Care to share?

Specsman 8)

 

Others have said this, but I want to back them up. The BOSE amplifier has a separate accessory wire to turn on than the head unit. Just add it to the accessory wire from your aftermarket stereo.

Sent from my iPhone using Tapatalk Pro

 

Hi everyone, confused ..... having read all of the above discussion about various connection wizardry, can I ask, why the standard concert head unit plus multi changer CD are not connect as standard to the rear two speakers and sub as supplied from build? My wife has recently acquired a 2000 Roadster Quattro, in mint condition,which was previously owned by an older lady who had kept all bills etc and would I assume never have messed about under any seats or certainly not behind any rear speakers. So why do the said rear two speakers and sub not work. Why would Audi fit speakers in rear that are an option to have working from new ?

 

Why would Audi fit speakers in rear that are an option to have working from new ?

Is it BOSE or non-BOSE?

For BOSE Roadster rear speakers and sub should have been connected from new. If they weren't it was a build error that went unnoticed by Audi QC!

Don't know enough about the non-BOSE Roadster speaker setup to say. Did it even have rears/sub?

 

@Specsman take a look on my radio build thread.
http://www.ttforum.co.uk/forum/viewtopic.php?f=2&t=1745586

I did the work around September but had the pics and just now found the time to post on the forum. Mind you, the speakers are shite and I discovered yesterday that on mine now the rears also don't work :x despite having a proper autoleads adapter. I remember they definitely worked when I put everything together. Maybe 4x50 fried them.

Made an impulse buy the other day which i know I'm gonna regret :lol: :lol: :lol:

Haven't fitted them yet. Front and rear cheapo alpines for about 100eur

 

Hi Smaler10. Copied this text from an old post (Acks to MrBrown):

"Re: 2003 225 Roadster- no Bose
27 Jan 2016, 20:25

The "non-Bose" Roadster (well at least in my 03) has a central sub with an amp mounted on the back of it. This amp drives the sub AND the rear quarter speakers. There's a good write-up here

http://mk1tt.montebellopark.com/subwoofer.html"

From that post, it sounds, (excuse pun), to me, like the rear amp is the place to start. I'd check 12V supply at the amp first, then each speaker. To do that, dab an ordinary battery, AA or similar across the two wires that go to the actual drive unit, if it's OK, you will hear a blip as the DC battery moves the cone, Let us know how it goes.

 

Thanks for the responses lads. Very useful. Firstly it is a non Bose, as in "standard Audi". Yes I can see through the speaker grills that all three rear speakers are fitted but no sound. On the concert head unit the fader control does allow rear fade but all this does is fade the door speakers down to nothing. Im having a few minor troubles with this 18 year old car that is only really a weekend toy for the wife. Is spends most of its life laid up under a small cover. I haven't really had the time to get stuck in, other than fixing the drivers door switch (window drop/interior light), passenger door window switch pushed into door handle (nightmare), Haldex earthing strap rusted off, rear window heat wires broken (convertible roof), oh and now the thermostat stuck open, it only runs at 60c thus not returning more than 24/ gall.
Thanks lads

 

Hi - first post so bear with me please! And no doubt a question asked a million times but can't find a definitive answer...

I have installed a Pioneer MVH-S300BT in my 2000 (W) mk1 TT - non Bose stereo, using Harness Adaptor PC9-401, and PC5-90 aerial adapter... but... no sound from rear speakers.

I know I have to add the blue wire to something... have tried directly off the remote wire from new HU but no joy.

A (idiot proof) description of what to do here would be greatly appreciated!

 

I know I have to add the blue wire to something... have tried directly off the remote wire from new HU but no joy.

A (idiot proof) description of what to do here would be greatly appreciated!

1. Did rears work before you removed old unit?
2. Assuming they did, is there +12v on the remote wire when new headunit is on?
3. If not, disconnect blue wire and temporarily connect to 12v from elsewhere (e.g. headunit supply) as a test. Do not leave like this though, or you will get a flat battery.