Duff front left BOSE speaker (S3)

[mramcha]

I've got a 2001 S3 with BOSE sound, and everything works fine except that my front left speaker has recently started making a buzzing noise.

I've faded and balanced and I'm sure that its only on that speaker/channel.

Couple of questions:

Is this likely to be a bad speaker, or a bad channel on the AMP. Does anyone know how I would find out?

Does anyone know how to get at the speaker in the door? Does anyone know where I could get a replacement.

Currently driving around with sound faded to the back speakers. (and its annoying me)

Mike

 

[AndyMac]

Does it just buzz, or is there sound coming out as well?
Is it at all volumes i.e. if you whack up the volume does it go away or get worse?
You need to remove the door card to get to the speaker, but it maybe just a dry joint on the amp as they have a tendancy to start playing up on older vehicles. Ebay is your best bet for a replacement speaker or amp. You might have to buy the whole system then flog off the bits you don't need though. There's plenty being sold as most people want shot of them.
Removing the doorcard: wind the window down, remove the 2 visible screws at either end of the doorcard (up by the window), then remove the screw inside the grab handle and push the plastic cuff down and remove the 2 main screws behind it.
Then pull the whole doorcard straight up and out, remembering you need to disconnect the door release and the electrics.

 

[mramcha]

It still plays, but with a background rumbly/buzzy/crackly sound.

At low volumes it is a continuous buzzy sort of noise. If you turn up the volume, the music gets louder, as does the buzzing.

How do I get to the amp and fiddle with the speaker connections?

Thanks,
Mike

 

[guyl]

Sounds like the exact same problem I have, except on the drivers side.

I think I have pretty much ruled out the speaker as I have had it out and tested it and there was no such buzzing, bus as soon as it went back in, it started again.

I have also checked to make sure nothing is touching the cone when it is mounted, causing it to vibrate.

Does yours 'warm up' in that it stops or quieten down after listening to the stereo for a while, or is particulary bad on cold/damp mornings?

Andy, you have mentioned a dry solder joint, have you attempted or fixed any before? I'm sure it is something I could have a crack at.

Guy

 

[mramcha]

The amount of buzzing it makes does vary. I've not been able to nail it down. It irritated me so much I've just faded everything to the rear speakers. I guess I should see if it gets better when warmed up.

The sound reminds me of the sound an AMP makes when the power transistor is blown, but I don't know if the BOSE amp works that way. Seems as if things are pointing in the amps direction.

I've just had a look in the right cubby hole in the boot, and It's not obvious to me how to take the amp out. i.e. theres ONE nut visible, I'm assuming there are more, but I can't reach/see/feel them.

Mike

 

[AndyMac]

There's 2 more underneath it.
I just run a soldering iron over the main solder joints on the amps PCB, the bigger ones for the power output stage. This has worked in the past for Bose amps that are working but intermittant or crackly.

 

[mramcha]

It has magically stopped buzzinf without me doing anything, however, I do recall it was bad on the last couple of really cold days.

Next time it happens, or if it gets worse, I'll follow AndyMac's advice and take the amp out and resolder the PCB joints. (There's a thread earlier on where AndyMac explains how to remove the panelling to get to the Subwoofer (on the left), I'll assume the method is identical for the right hand side to get to the amp.)

Thanks for all your help.

Mike

 

[guyl]

If the weather plays ball, i think i am going to have a look at mine over the weekend.

I haven't taken the drivers side trim off before, whereabouts is the amp lurking?
Is there anything special i should be aware of before i have a look?

 

[guyl]

OK, had the amp out and all solder joints looked OK.
Tried a new (secondhand) amp that was confirmed to me by Ash_S3 that wasn't buzzing, and that still buzzed.

What else can i try? as this buzzing is starting to get on my wick!

Any suggestions Andymac?


Thankyou!

 

[AndyMac]

Has to be the wiring to the speaker then or the pre-out wiring from the HU to the amp. Can't remember on the S3 of there's a multiplug under the dash that takes the wiring from the cabin into the trunking for the door. There is on the A4 and it's a bitch to get as it's inside the void between the outer & inner skin. This connection can get "dirty" and cause speaker drop outs but shouldn't cause buzzing, unless the buzzing is related to the music it's playing i.e. buzzes only on the kick drum etc.
Ususally jacking the volume up overcomes the electrical resistance of the dirty connection so it only happens at low volume.
I have seen a HU fault that gives you a detuned radio sound through the duff channel, only cured by a new HU.
Is the buzzing there with no music playing?

 

[guyl]

Right, just been out for a little play as i haven't had my car for a month.

The buzzing is only on a certain range, especially speaking, so if there is a silent moment, there is no buzzing.

I have checked all speakers, by moving the fader and balance around, and while the OSF is by far the worst, the NSF is also buzzing a small amount.

I have tried turning the volume up to overcome any electrical resistance, but the buzzing remains.

The headunit wiring disapears behing the dash, but then goes through the rubber concertina boot from the chassis to the door, from there the cables run up to the connectors roughly behing the handle (these are a bitch to get on and off)

Does this shed any more light on what might be the cause?

 

[dualmono21]

its the shield connection on the amplifiers input
try re-soldering it to make sure it has a good connection that should eliminate the problem

 

[guyl]

where abouts on the amp?

Again, thanks for your help!

 

[AndyMac]

I thought we'd ascertained that the amp was OK by trying another amp and getting the same fault?
So as I said previously my money is on the wiring.
Is it just the fronts or are the rears the same?

 

[dualmono21]

if youve tried another amp allready and it was fine
look for the shield connection on the wiring itself and re-solder it to the ground connection

 

[quattrojim]

i also have this exact same problem, i was going to change the speakers but i take it the buzzing will still be there?

what is the shield connection?