1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Dismiss Notice

Help with wiring and Rear volume

DrEvil Dec 28, 2015

  1. DrEvil

    DrEvil Registered User

    315
    23
    18
    I've recently got a replacement (Android style) head unit which replaces my concert II. The car is an A4 avant style with rear amplified speakers (front driven directly from HU).

    Having connected it up and got it all working ok, my rear speaker volume is very low (but the sound is clear). I've done some digging around and suggestions appear to range from
    1) making sure the rear amp is getting switched power
    2) directly wiring speakers to HU
    3) ditching the rear amp for something better
    4) HiLo converters.

    I am a relative newbie to all this and would like to get this up and running better without the $$ of new amps for now.

    I have looked on my HU and there is a "AMP CON" wire out. But I am not sure where this would connect up to the old harness. My old concert II diagram was like this one and so I have the "speaker side" connector which matches up to this one:
    [​IMG]

    Where should the AMP CON connect to.

    Also does anyone have a list of what these abbreviations stand for (I get most of them but AU PL? CDC? etc)

    Thanks
     
  2. Avatar

    snack-media
    Advertisement


  3. john777w

    john777w Registered User

    650
    86
    28
    Is there a can box attached to your unit, I used an output off that to power/activate the rear amp. On mine it was a blue wire, but you need to test with a meter! There's no switched ign feed behind the radio, so the can bus box is the only way to switch the amp.
     
  4. DrEvil

    DrEvil Registered User

    315
    23
    18
    I have a multimeter so I will check that and I do have a can bus. Once I have identified the right switched wire, do you know what is the wire to the amp which I connect it to?
     
  5. john777w

    john777w Registered User

    650
    86
    28
  6. DrEvil

    DrEvil Registered User

    315
    23
    18
    Mine is also non-bose, just amplified rear speakers. I'll take another look in the daylight and see if I can figure it out.

    Thanks!
     
  7. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    You may need to run a hi/lo converter on the rear speaker outputs.
     
  8. DrEvil

    DrEvil Registered User

    315
    23
    18
    OK, think I managed to figure it out. Dsp ein is the amp power on and it was connected to 12v line. So did a Hilo convertor and up and running now.

    Thanks all.

    Docurley, we're you trying a DAB (from AZ?)
     
  9. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    Parts turned up crushed and I mean crushed., once removed from the packaging they all just fell apart so waiting for a replacement DAB.
     
  10. yorkster001

    yorkster001 Registered User

    99
    6
    8
    My apologies for what might appear to be a dumb question, but it I use the remote switch on from my Kenwood HU straight to the amp signal feed I don't need a HILO convertor right?
     
  11. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    Audi use a amp for the rear speakers Bose or standard so you can't use the speaker outputs from a aftermarket system.
     
  12. Avatar

    snack-media
    Advertisement


  13. yorkster001

    yorkster001 Registered User

    99
    6
    8
    Hi, thanks for your reply. I'm using RCA output from the HU but need a signal wire to kick the amp in. The HU has a remote wire for this purpose but struggling to find the corresponding wire on the Audi loom for the amp.
     
  14. DrEvil

    DrEvil Registered User

    315
    23
    18
    Which car have you got and do you have a pic of the loom. For mine it was 'dsp ein'.
     
  15. yorkster001

    yorkster001 Registered User

    99
    6
    8
    I have an 07 Plate saloon with non-bose audio. Here's where I've got to:
    • Wired rear speaker wires from loom to RCA plugs
    • Connected pre-outs from HU (Alpine W928R) to rear speaker RCA's
    I'm happy these are working as I get audio albeit not amp'd. My issue is the HU has a remote out which it specifies is for amp. I'm assuming this is the amp signal wire but I can't work out what to connect it to on the loom, The wires on the loom that is connected to 'DSP Ein' does nothing when connected to the HU remote wire. From what I've read the amp signal wire is white, however I can't find this anywhere on the loom at the dash end. I'm trying to avoid a trip to a stealership or car audio specialist but not looking good.

    Any help, advice would be greatly appreciated.

    Cheers
     
  16. john777w

    john777w Registered User

    650
    86
    28
    Just a thought, have you tested the output from the "amp out" wire? Is it 12v?
     
  17. yorkster001

    yorkster001 Registered User

    99
    6
    8
    Good point, as good a place as any to start.

    Would I be correct in saying the OEM amp is already powered, the feed from the head unit is just to switch it on? If it does show 12v I'm guessing I need a high low convertor?
     
  18. sline29

    sline29 Registered User

    169
    38
    28
    Hi mate
    Any chance you could post pics of how yours is wired up?
    Having trouble getting my rears to sound any good
     
  19. DrEvil

    DrEvil Registered User

    315
    23
    18
    Have replied to you pm.
     
  20. DrEvil

    DrEvil Registered User

    315
    23
    18
    Hey docurley - did you get your replacement through?
     
  21. lincoln_dj

    lincoln_dj Active Member VCDS Map User

    483
    65
    28
    Hi guys. I've got an android stereo now too, replacing rns-e so it's quad lock not iso loom. In a 2007 s3.

    Got the same issue with very low volume at the rear/sub.

    Have identified the pin to activate the amp, and there is 12v going to it from the stereo so assume the issue is with the line signal?

    Currently fronts running straight off HU and rears via "line" RCA output from the stereo. Do I need to boost the RCA output or does the amp need activating another way?

    Would assume there'd be no rear sound at all with amp off?

    Cheers
     
  22. DrEvil

    DrEvil Registered User

    315
    23
    18
    Hey lincolndj - so this is where you need to connect the rear amp to run directly off the HU, but with a HiLo convertor. I had a discussion sline, and I'll if i can cross post some pics from that conversation...
     
  23. DrEvil

    DrEvil Registered User

    315
    23
    18
    So essentially you need to cut and connect the wires from the HU direct feed to Rear speakers (note your HU pic may vary slightly) on this:
    [​IMG]
    to one of these type things:
    [​IMG]
    and then connect this to your rear amp R and L.

    Hopefully that makes sense!
     
    lincoln_dj likes this.
  24. lincoln_dj

    lincoln_dj Active Member VCDS Map User

    483
    65
    28
    cheers mate. So guess I'm better off using the HU amped rears and reducing the line voltage with one of them, as opposed to sticking with the HU RCA rears which seem like they're too quiet for the audi rear amp - as that would need to be a powered booster!

    Are the adapters in Halfords any good or am I better off ordering online and waiting a few days?

    cheers
     
  25. DrEvil

    DrEvil Registered User

    315
    23
    18
    I ordered one, actually the same as the Xtrons one it the pic above from Fleabay. Came promptly enough and was only around £5.80. Don't know about Halfords ones. Wanted to get a SNI35 as thats what everyone seems to use and like on AZ, but can't seem to get that over here.
     
    lincoln_dj likes this.
  26. uniqueflh

    uniqueflh Registered User

    6
    0
    1
    Audi Rear Amp (non-Bose).JPG So. New to this forum. And I hate to be 'that guy' who brings a topic back from the dead...but there is all sorts of nonsense out there regarding this whole rear amp'd non-Bose speaker thing.

    I just grabbed a replacement H.U., have no rear sound...and want to make sure I am going to be connecting the Line-Level Converter properly when it gets delivered Friday.

    Does this look proper?

    Thanks in advance guys (and girls).
     
  27. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    incorrect......... each speaker channel will have its own negative not a common negative but you will see that when you go to connect as the solid colour for the speaker output is a solid colour and the negative will be the same colour but with a black stripe running through it, the blue and white wire will be the lead you need to connect to to turn the converter on and off.
     
  28. uniqueflh

    uniqueflh Registered User

    6
    0
    1

    I know the aftermarket harness will have dedicated positive & negative wires. But which pin(s) on the OEM radio are for rear negative?

    Pin-out diagram on the factory radio is unclear.
     
  29. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    Your loom from the radio should have RCA's going to the Audi loom
     
  30. uniqueflh

    uniqueflh Registered User

    6
    0
    1
    Yeah. That would make it simple, but the Audi loom is just the 'quad lock' connector, and has no OEM RCA connectors for the rear.

    In my research, some older versions of the Concert radio had a shared ground for the rear channel(s).

    I dunno. Feel like I am just missing something simple/obvious here.
     
  31. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    Take a picture of the loom and I will see if I can help
     
  32. uniqueflh

    uniqueflh Registered User

    6
    0
    1
    Ask. And you shall receive...
     

    Attached Files:

  33. Avatar

    snack-media
    Advertisement


  34. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    I need a pic of the HD unit loom that connects to that plug
     
  35. uniqueflh

    uniqueflh Registered User

    6
    0
    1
  36. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    [​IMG]
    OK so this is the loom and it will have the RAC's for you to connect to after you splice in to the speaker outputs for the rear in the same part of the loom and its the image top left . Easy job.
     
  37. uniqueflh

    uniqueflh Registered User

    6
    0
    1
    The harness diagram should indicate what signal pins from the new HU should connect to. That pic is from the top of my OEM radio...and the only thing that is unclear is the rear speaker configuration.

    Front outputs are clearly marked with both positive/negative pins. While the rear appears to be indicated as:

    LINERR (right rear +)
    LINERL (left rear +)
    LINE (a common ground)

    A previous post mentions the DSPEIN pin should provide 'remote on' for the factory amp.
     
  38. docurley

    docurley Moderator Staff Member Moderator

    4,084
    94
    48
    No need for pins just tap the loom speakers and plug in to the RAC's
     
    Last edited: Jul 7, 2016
  39. Chris Small

    Chris Small Registered User

    2
    0
    1
    Hi

    I have this problem I have just installed xtrons head unit everything works fine except the rear speakers are very quiet. Even the phone button on wheel works with the head unit etc.

    How do I resolve the issue with the speakers the fronts are very loud but tears aren't.
     

Share This Page

Do Not Sell My Personal Information