Announcement

Collapse
No announcement yet.

Understanding E30 speaker and amp wiring

Collapse
This is a sticky topic.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Understanding E30 speaker and amp wiring

    Posted this to Luke's wiring thread, but think it warrants it's own post. Should probably sticky this too.

    Radios like the CM5908 (Alpine) and KE83ZBM (Pioneer) have 4 amp channels (and a CD changer connector). The earlier radios like the CM5905, CM5907 and KE81ZBM only have 2 amp channels. You have probably seen pics with early model E30s showing an external fader knob below the center AC vents. That fader was how a 2 channel radio drove 4 sets of speakers in the early model cars.

    All cars with the BMW Sound System came with a 4 channel Blaupunkt car amp in the trunk, tweeters in the doors and for coupes and sedans tweeters on the package tray shelf as well. Regardless of whether your radio was 2 channel or 4 channel, if it came with the Blaupunkt amp the output wires from the radio / head unit share a common “signal ground”. This means there is a single shared ground connection for all audio channels out of the radio, not separate ground wires for each channel. This common speaker ground is 1 or 2 brown wires that get screwed on to the back of the radio heatsink

    AUDIO WIRING ON COUPE/SEDAN VS CONVERTIBLE VS TOURING..

    If you really go nuts on realoem, or even better are fortunate enough to study the actual audio wiring on the various E30 body types, you will note that the audio wiring on a coupe or M3 is different from a convertible - or a touring. This is mostly due to speaker placement, but also wiring changes were introduced in Europe during E30 production that were not present elsewhere.
    • Up to 1986, all installs were 2 channel systems with a FLAT BLADE FADER CONNECTOR. Both radio-only and sound system harnesses were used.
    • Starting in 87, there's a 61-12-1-381-719 harness part number used sound system on coupe, sedan or M3. It used a ROUND PIN FADER CONNECTOR
    • Starting in 87, there's a different 61-12-1-381-718 harness part number used for sound system on convertible. This also used a ROUND PIN FADER CONNECTOR
    • Convertibles add a *really* bizarre speaker harness that routes from the driver side kick panel to the other 3 corners of the car. Also weird is that this harness uses the "radio only" wiring color scheme (more detail follows) that connects to a 6 pin connector near the driver front kick panel speaker with the rear amp out speaker wires. It seems that BMW intended to connect to all four speakers with this added harness at one point, but decided to use only the rear speakers for production. The most likely explanation was the need for individual speaker grounds (i.e., there can only be 2 grounds available for 4 speakers on a 6 pin connector)
    • The wiring in both the 718 and 719 sound system harnesses changed to a twisted pair setup at some point, but the part number was not changed. BMW Classic could not confirm the exact date of the production design change, but it most likely was most likely near the time 4 channel radios were being introduced.
    • FOR EUROPE ONLY​, some late model E30s including the tourings used the 17 pin connector found in early E36 cars that eliminates the fader connector and combines all the wiring for it with the other power and ground wiring that went to the radio. Tourings all came with 17 pin harnesses, part numbers 61-12-1-394-213 (sound system) and 61-12-1-394-212 (radio only). Part numbers for coupe/sedan/M3 are 61-12-1-394-211 (sound system) and 61-12-1-394-210 (radio only). For convertibles, there were 17 pin harnesses as well, 61-12-1-394-215 (sound system) and 61-12-1-394-214 (radio only).
    So that means there are many combinations of audio wiring in E30s:

    Worldwide, including Europe only options:
    SIX DIFFERENT SETS OF RADIO/AMP WIRING IN E30 COUPES OR SEDANS, FOUR FOR CONVERTIBLES AND TWO FOR TOURINGS

    for USDM (US & Canada):
    FOUR DIFFERENT SETS OF RADIO/AMP WIRING IN E30 COUPES OR SEDANS, TWO MORE FOR CONVERTIBLES

    I have included FIVE of the wiring diagram combinations below:

    Coupes/Sedans with the BMW SOUND SYSTEM (premium sound)
    A: 2 Channel Radio with BMW SOUND SYSTEM (with the fader knob, up to early 88)
    B: 4 Channel Radio with BMW SOUND SYSTEM (starting late 88)

    Coupes/Sedans with Radio Only (standard setup)
    C: 2 Channel Radio Only installation (with the fader knob, up to early 88)
    D: 4 Channel Radio Only (starting late 88, very similar to the 2 channel radio only wiring, but there is no fader)

    E: Convertibles with BMW SOUND SYSTEM (premium sound)

    F: Euro model cars including euro-only Tourings (not available in USDM) equipped with a new 17 pin radio connector that was later included with E36 vehicles, radio only or with BMW SOUND SYSTEM. Electrically this wiring setup was identical to the equivalent E30 sedan radio only or BMW SOUND SYSTEM install. The difference is primarily as follows:

    - there's no separate fader connector
    - except for the antenna cable itself, all the audio wiring routed to the dash radio area terminate at the 17 pin connector.

    HARNESS ADAPTERS IN 4 CHANNEL CARS (EXCEPT TOURING)
    In common speaker ground, 4 channel premium sound cars, the headunit wiring included a 2 to 4 channel adapter harness that replaced the fader, plugged in to the same connector the fader used. One end of this adapter plugs into the round pin fader socket in the wiring harness. The other end is a rectangular connector with 4 blades labeled LH (links hinten = left rear) and RH (rechts hinten = right rear). Those are the rear head unit output connections that get sent to the amp in the trunk.

    Here is a standalone picture of the 2 to 4 channel adapter for BMW SOUND SYSTEM / premium cars, part number 61-10-1-388-934

    Note that there are no ground wires in that harness.

    There is also a separate 2-to-4 channel E30 adapter harness for cars that came with 2 channel radio only installs, 65-12-1-379-329. This harness only worked with round pin fader connector wiring, and includes individual speaker grounds for each channel.



    There was a flat blade fader adapter for 85-86 4 channel conversions as well, 61-12-1-386-161. I've personally never seen one of these. but I make a replacement based in part on 65-12-1-379-329​.


    RADIO / HEAD UNIT AUDIO OUT WIRING (ACCESS FROM THE RADIO OPENING OF COURSE)

    You can tell what the head unit output wires do from the color coding:
    blue head unit wires are for the right channels
    yellow head unit wires are for the left channels
    if they have no stripes they are for the front channels
    wires with red stripes are also for the front channels
    if they have black stripes then they are for the rear channels


    TRUNK AMP WIRING FOR BMW SOUND SYSTEM

    Now regarding the BMW SOUND SYSTEM wiring, those head unit outputs get routed to your blaupunkt trunk amp harness - NOT TO THE SPEAKERS. Unfortunately, due to age it's about 90% certain that a 30 year old unserviced power amp is fried, even if the system was lightly used. If your OEM radio hasn't been serviced either, it's also likely that the amp inside the radio needs service as well - both need to be functioning properly to get good amplified sound. If your trunk amp is indeed damaged, you will either not hear sound from some or all of the speakers, or it will be severely distorted. Right now there are three options available to resolve this situation (I hope to have some others for the community soon):

    (Case 1) replace or rebuild the blaupunkt trunk amp. if you're a collector this may be your preference, but honestly it's pretty old tech.

    (Case 2) run headunit only, and bypass the trunk amp by modifying the harness at the amp connector in the trunk or under the rear seat. how you do that depends on whether you have a 2 channel radio+amp harness or a 4 channel radio+amp harness. Once you do this the headunit is now directly connected to your car speakers.

    (Case 3) cut the trunk amp connector or splice in to the trunk wires, then replace the trunk amp with an aftermarket 4 or 5 channel amp. This gives you the most flexibility to do things like add a trunk sub, and also preserves the option to keep the factory radio.

    HOW TO DO A TRUNK AMP BYPASS PROPERLY - DIFFERENT FOR 2 AND 4 CHANNEL

    SPEAKER GROUNDS, OUTPUT GROUNDS AND CHASSIS GROUNDS - THEY ARE NOT THE SAME!!
    The speaker ground connections on the actual speakers vs the radio and amp grounds. with a no-amp system the speaker grounds are the same as the output ground connections on the radio. that's not the case on a BMW SOUND SYSTEM setup with trunk amp. you can see all of this in the schematics:

    1) in a no amp system, the speaker grounds are connected to the radio outputs, not to the radio chassis. the radio chassis itself is grounded separately.

    2) if you have the trunk amp, the speaker grounds are connected to the amp outputs, not the amp chassis. the amp chassis is grounded separately. the radio chassis is also grounded separately, and only the positive radio outputs are used.

    If you read the above carefully, you'll notice the speaker grounds are never grounded to the chassis directly in either setup.

    4 CHANNEL TRUNK AMP BYPASS
    @Rontgen's post on Luke's amp bypass thread beautifully captures the 4 channel radio harness wiring changes you need for case 2,


    2 CHANNEL TRUNK AMP BYPASS
    UPDATED DESCRIPTION OF 2 CHANNEL GROUNDS Mar 10 2023
    CORRECTED Sep 4 2022: with the older 2 channel amp bypass is similar, except that there is a single brown/black ground wire between the radio and amp that MUST STAY SEPARATE from the amplifier output ground wires going to the speakers.
    See this post further down for additional clarification https://www.r3vlimited.com/board/for...9#post10067179

    BMW SOUND SYSTEM AFTERMARKET AMP HARNESS MODIFICATIONS
    For case 3 you route the yellow and blue wire pairs to the aftermarket amp's speaker level inputs, and the aftermarket amp's outputs get wired to the black and grey striped wires that go to the four speaker sets.

    Here are the power amp output wiring colors (probably posted for the 135th time lol).

    for both the 2 channel and 4 channel radio harnesses:
    grey amp wires are for the front speakers
    black amp wires are for the rear speakers
    grey or black wires with red stripes are left channel
    grey or black wires with violet / purple stripes are left channel ground
    grey or black wires with white stripes are right channel
    grey or black wires with brown stripes are right channel ground

    and for 2 channel radio harnesses only:
    brown wire with black stripes are chassis grounds between the amp and the radio. They are connected to a brown chassis ground wire, separate from speaker grounds


    the three remaining power amp wires are self explanatory, red for battery, white for amp on/off and brown for ground.

    FYI I'm working on a couple of plug and play adapter harnesses for all this so no wire cutting is needed, but will be a while. First install will be Cosmo, my 86 Cosmoblau 325. It will be running an Infinity REF 4555A 5 channel amp and a JBL 1224SS trunk sub.

    ADVICE ON READING BMW ELECTRICAL DIAGRAMS (SCHEMATICS)
    Don't be afraid of them. Some rules of thumb:
    - diagrams are usually drawn with the positive polarity at the top, ground at the bottom
    - every wire has two letter color codes (e.g. BK/BR means Black wire, Brown stripe) and a wire size in mm (usually 1.5, 1, .75. .5). This is super handy to identify specific wires in the car by both how big they are and their color scheme
    - the diagrams just show connections between things, not where they are in the car, or how long the wire really is. this is usually what confuses people.

    A. TWO CHANNEL BMW SOUND SYSTEM (COUPE / SEDAN)
    for completeness, here's a 1986 BMW Sound System schematic for TWO CHANNEL RADIOS showing the wiring for the radio, amp, speakers and power antenna. Note the radio output wiring is common ground. NOTE AS WELL - 1986 and earlier cars used a FLAT BLADE FADER rather than the ROUND PIN FADER used 1987-1989.



    B. FOUR CHANNEL BMW SOUND SYSTEM (COUPE/SEDAN)
    Here's the same set of schematics for a 1989 late production BMW sound system car with FOUR CHANNEL RADIO wiring. Again the radio output wiring to the power amp is a common ground setup.


    C. TWO CHANNEL RADIO ONLY (COUPE/SEDAN)
    This is how the 2 channel radio was wired up to early 88, which uses a fader switch with widely spaced ridges on it and round pins. There's actually an older setup that is missing a ground wire from the fader switch too. The older fader adjuster has a much smoother finish to it.


    D. FOUR CHANNEL RADIO ONLY (COUPE/SEDAN)
    Finally, here's an 1989 4 CHANNEL RADIO ONLY late production schematic. Note each speaker has its own ground wire. Early production is electrically the same with some harness connector differences

    NOTE The 1989 325i / 325is electrical troubleshooting manual has 4 different radio + amp schematics based on early vs late production, radio only vs BMW Sound system. Make sure you're looking at the right version for your car!
    -- 2 channel (up to early 88 or so) or 4 channel radio
    -- radio only, or BMW Sound System with amp
    -- coupe/sedan or convertible. Convertibles with BMW Sound System do not have rear tweeters, or crossovers on the rear speakers.

    E. FOUR CHANNEL BMW SOUND SYSTEM (CONVERTIBLE)
    This configuration is electrically identical to a four channel BMW SOUND SYSTEM install in a coupe or sedan, with exceptions due primarily to the rear speakers being in a different location:

    Last edited by bradnic; 03-12-2024, 06:31 AM.
    I BUY/SELL REFURBISHED CM5907s & CM5908s

    HOWTOs:
    DB vert plastic bumpers
    OEM Keys
    MTech1 docs

    88 ix Lach/Card
    91 ic Calypso 3.1
    86 Cosmo 2.7

    OEM+ or bust!


    reelizmpro: I will always be an e30 guy.. I still do all of my own labor
    TrentW: There's just something so right about a well-built M20 in an E30
    e30m3s54turbo: I save my money for tuner parts.

    #2
    Any suggestions for a newer amp to install in the stock trunk location? Or is it not worth the trouble?
    "Time doesn't heal anything... It just teaches us how to live with the pain." - My Cracked Dashboard

    Comment


      #3
      Originally posted by Zambuzan View Post
      Any suggestions for a newer amp to install in the stock trunk location? Or is it not worth the trouble?
      I’m actually working on an amp bypass kit that uses the existing amp housing. You’ll be able to use a 5 channel amp and a trunk sub with it. Aiming the first install on my 86 325, using an Infinity Reference 4555a and a JBL 1224Ss 12” trunk sub. Just finished a BMW Sound System rear parcel shelf retrofit on that car actually. Front tweeters are installed too, and have the OEM front speakers on order from Germany.
      I BUY/SELL REFURBISHED CM5907s & CM5908s

      HOWTOs:
      DB vert plastic bumpers
      OEM Keys
      MTech1 docs

      88 ix Lach/Card
      91 ic Calypso 3.1
      86 Cosmo 2.7

      OEM+ or bust!


      reelizmpro: I will always be an e30 guy.. I still do all of my own labor
      TrentW: There's just something so right about a well-built M20 in an E30
      e30m3s54turbo: I save my money for tuner parts.

      Comment


        #4
        Originally posted by bradnic View Post
        I’m actually working on an amp bypass kit that uses the existing amp housing. You’ll be able to use a 5 channel amp and a trunk sub with it. Aiming the first install on my 86 325, using an Infinity Reference 4555a and a JBL 1224Ss 12” trunk sub. Just finished a BMW Sound System rear parcel shelf retrofit on that car actually. Front tweeters are installed too, and have the OEM front speakers on order from Germany.
        Wait wut? You mean to physically place that Infinity amp in the OEM trunk location? Am I misunderstanding? Or do you mean modifying the internals of the OEM amp?
        I should've added in my original post that my goal would be to have an amp hidden, aka not taking up trunk space, just like the factory amp.
        "Time doesn't heal anything... It just teaches us how to live with the pain." - My Cracked Dashboard

        Comment


          #5
          Yes basically an integrated amp+trunk sub connected through the OEM trunk amp housing. No cut wires. If you’re going to install a trunk sub anyway, this is probably the best option

          If you’re lucky enough to have original BMW Sound System wiring it will be plug-n-play to upgrade power and add a trunk sub... well for coupes and sedans with trunk battery locations anyway.

          EDIT: I will have two different harness types.. if you're just adding a powered trunk sub it will simply tap into the premium amp wiring directly. Super easy.
          Last edited by bradnic; 06-30-2019, 11:29 AM.
          I BUY/SELL REFURBISHED CM5907s & CM5908s

          HOWTOs:
          DB vert plastic bumpers
          OEM Keys
          MTech1 docs

          88 ix Lach/Card
          91 ic Calypso 3.1
          86 Cosmo 2.7

          OEM+ or bust!


          reelizmpro: I will always be an e30 guy.. I still do all of my own labor
          TrentW: There's just something so right about a well-built M20 in an E30
          e30m3s54turbo: I save my money for tuner parts.

          Comment


            #6
            Originally posted by Zambuzan View Post
            I should've added in my original post that my goal would be to have an amp hidden, aka not taking up trunk space, just like the factory amp.
            Answering your question directly, a class D 4 channel amp could potentially fit in the original amp housing. It’s a lot of work though. You can accomplish the same thing with an amp bypass and wiring in a small commercial class d amp. It does require cutting the harness though. The key issue is sourcing the connector on the amp housing. I haven’t been able to find it yet.
            I BUY/SELL REFURBISHED CM5907s & CM5908s

            HOWTOs:
            DB vert plastic bumpers
            OEM Keys
            MTech1 docs

            88 ix Lach/Card
            91 ic Calypso 3.1
            86 Cosmo 2.7

            OEM+ or bust!


            reelizmpro: I will always be an e30 guy.. I still do all of my own labor
            TrentW: There's just something so right about a well-built M20 in an E30
            e30m3s54turbo: I save my money for tuner parts.

            Comment


              #7
              Originally posted by bradnic View Post
              Answering your question directly, a class D 4 channel amp could potentially fit in the original amp housing. It’s a lot of work though. You can accomplish the same thing with an amp bypass and wiring in a small commercial class d amp. It does require cutting the harness though. The key issue is sourcing the connector on the amp housing. I haven’t been able to find it yet.
              Any luck with this? I am thinking I can use the radio output lines to feed signal to a digital sound processor. It would be great to just plug in a harness instead of the factory amp so, the factory harness is saved. I am not sure what kid of wattage is coming out of the OEM head unit. Would I wire the signal to speaker level inputs or adapt them to an RCA input?

              Comment


                #8
                If you can't find the stock amp connector anywhere, you might consider replicating it in CAD and 3D printing it.

                There are lots of places to get high quality 3D prints now a days. Stratasys, Xometry, ProtoLabs to name a few.

                Comment


                  #9
                  Lets face it. BMW makes sh*tty stereo's. The speakers wires are ok. Get a new head unit, a quality amp and some good speakers with some sub setup. Install. I use to stick a HUGE PPI 4800.2 on trunk wall between tail lights.Right next to the battery and took up very little trunk space flat against the rear valance panel.

                  Comment


                    #10
                    @dimrun2002 I respect your view, but generally disagree.
                    - The E30 headunits were made by Alpine and Pioneer, not BMW.
                    - The BMW Sound System speaker drivers are very high quality actually.

                    DIY Areas for improvement from the original setup:
                    - If you have the radio only standard setup then definitely replace all the speaker drivers with better stuff
                    - If you have a convertible replace the rear speakers with coaxial drivers

                    Advanced upgrades from the original setup:
                    - Retrofit the BMW Sound System. this is a significant undertaking though that includes replacing the main rear speaker harness, all of the speaker drivers, adding tweeter wiring and door tweeter pods. It's definitely worth it if you don't have it, but sourcing all the bits is difficult.

                    - Add a powered sub to a BMW Sound System setup. Requires some custom harness work.

                    - Replace the premium amp with an external 5 channel amp and a passive sub.
                    I BUY/SELL REFURBISHED CM5907s & CM5908s

                    HOWTOs:
                    DB vert plastic bumpers
                    OEM Keys
                    MTech1 docs

                    88 ix Lach/Card
                    91 ic Calypso 3.1
                    86 Cosmo 2.7

                    OEM+ or bust!


                    reelizmpro: I will always be an e30 guy.. I still do all of my own labor
                    TrentW: There's just something so right about a well-built M20 in an E30
                    e30m3s54turbo: I save my money for tuner parts.

                    Comment


                      #11
                      Originally posted by NeverEnough02 View Post
                      Any luck with this? I am thinking I can use the radio output lines to feed signal to a digital sound processor. It would be great to just plug in a harness instead of the factory amp so, the factory harness is saved. I am not sure what kid of wattage is coming out of the OEM head unit. Would I wire the signal to speaker level inputs or adapt them to an RCA input?
                      There are line level/output converters out there if you want to use external amps and line level inputs..
                      Here’s a good Crutchfield article about them

                      I did get an Infinity Basslink DC powered sub (10" driver+ 10" passive radiator) setup working with the existing premium amp. but it's too big for my vert :-)
                      Sounds darn good though.

                      Still looking for the connector. I will have two plug-n-play two harness adapter kits when I'm finished:

                      -- one to keep the OEM blaupunkt premium amp and add a powered sub.
                      -- one to replace the OEM premium amp with an external 5 channel amp and sub.

                      Originally posted by dlmrun2002 View Post
                      I use to stick a HUGE PPI 4800.2 on trunk wall between tail lights.Right next to the battery and took up very little trunk space flat against the rear valance panel.
                      That's a cool mount location but you do need to extend wiring back around further. Most folks probably mount behind their rear seat.

                      Looks like the PPI 4800.2 is a 4 channel amp. Infinity sells a Reference 4555 5 channel that's smaller, $100 less and supports 500W to the sub. you don't really need big power for the other channels - 45W should be enough for most folks.

                      Click on pic for Crutchfield listing


                      Stay tuned..
                      Last edited by bradnic; 07-30-2023, 06:12 AM.
                      I BUY/SELL REFURBISHED CM5907s & CM5908s

                      HOWTOs:
                      DB vert plastic bumpers
                      OEM Keys
                      MTech1 docs

                      88 ix Lach/Card
                      91 ic Calypso 3.1
                      86 Cosmo 2.7

                      OEM+ or bust!


                      reelizmpro: I will always be an e30 guy.. I still do all of my own labor
                      TrentW: There's just something so right about a well-built M20 in an E30
                      e30m3s54turbo: I save my money for tuner parts.

                      Comment


                        #12
                        Originally posted by bradnic View Post
                        I’m actually working on an amp bypass kit that uses the existing amp housing.
                        Awesome! Let's see some work!


                        Originally posted by bradnic View Post
                        @dimrun2002 I respect your view, but generally disagree.
                        - The E30 headunits were made by Alpine and Pioneer, not BMW.
                        - The BMW Sound System speaker drivers are very high quality actually.
                        Yhe stock BMW speakers are crap. They are fantastic if you consider 1990's factory car speakers as a baseline. But even driven with a nice amp, they are muddy, with a ton of resonance that make it sound like there is a midget ringing a bell, all the while banging on a Amazon cardboard box in your e30.

                        Luke Fisher tried to get us all to go down that rabbit hole.
                        Originally posted by Matt-B
                        hey does anyone know anyone who gets upset and makes electronics?

                        Comment


                          #13
                          I couldn’t disagree more with you George, but to each his own
                          I BUY/SELL REFURBISHED CM5907s & CM5908s

                          HOWTOs:
                          DB vert plastic bumpers
                          OEM Keys
                          MTech1 docs

                          88 ix Lach/Card
                          91 ic Calypso 3.1
                          86 Cosmo 2.7

                          OEM+ or bust!


                          reelizmpro: I will always be an e30 guy.. I still do all of my own labor
                          TrentW: There's just something so right about a well-built M20 in an E30
                          e30m3s54turbo: I save my money for tuner parts.

                          Comment


                            #14
                            Hi...if you are wiring a car that did not have a factory amp, you'll have 4 twisted pairs that run to or near the head unit location. Sometimes you'll have to cut back the harness wrap a bit to find them. Each pair is a +/- set with the signal wire color as described above and the brown stripe wire the return ground. Wire the speakers as specified by the head unit manufacturer.

                            pcb assembly
                            Last edited by JeffWiley; 08-22-2019, 09:06 AM.

                            Comment


                              #15
                              Hey this maybe off topic. I’m new to R3V. Just wondering if I can get some help. My front and rear speaker aren’t working on the drivers side of my e30 sedan. What could the possible issues be? I’m not familiar with wiring etc.

                              Comment

                              Working...
                              X