Help me find my HiFi amp please.

[Spivey]

I have a 2007 E85 roadster. VIN decoder says the following and I have counted 10 speakers.

S639 Preparation F Mobile Phone Cpl. USA/CDN
S645 BMW US Radio
S662 Radio BMW Business CD
S676 HiFi Speaker System
S692 Preparation, BMW 6-CD Changer I-Bus

Hooking up new head unit with correct wiring produces no sound with functioning head unit.
What I read on these forums is a dsp amp should be in the battery compartment but I don’t see any. Pictures below are battery compartment and sub woofer behind seat which is not branded carver or anything.

 

[DaveP]

I think you have the middle-tier audio option, which is 10 speakers but no amp/DSP in the boot. In my old car which had the Carver system, the amp/DSP sat in the gap behind your battery.

Bottom tier is the terrible 6-speaker, and I believe the top tier option is called out as "DSP" or "Carver" on the VIN decoders.

 

[Spivey]

I had thought if this was the case, then hooking up a head unit would just work. I guess I’ll figure out a way to test the head unit.

 

[Zedebee]

Nope. There are three hi-fi options. 6-speaker, 10-speaker or 10-speaker DSP. Both 10-speaker options have an amp in the boot. They are mounted in the same place but look visually different. Option 676 is the non-DSP 10-speaker system. Your amp has been removed, which is why the sound is not working correctly. Sometimes they go bad due to water in the battery compartment, but also they fetch money.

 

[Spivey]

Ok I found it! It was on the back wall of the trunk closest to the seats. Seems to be stock install and not moved by previous owner. Anyway it’s the Lear model, says non-dsp when I looked it up. So why doesn’t it work hooked up to new head unit. All 10 speakers currently work fine when hooked up to stock business radio. There is also a silver metal box back there which I don’t know it’s function

 

[Zedebee]

Well you learn something everyday. The 10-speaker amp is mounted in the battery compartment to 12/2005 and on the rear firewall from 01/2006, according to NewTIS.

 

[Mr Tidy]

Probably because BMW created the M in 2006 with the battery on the boot floor!

 

[Simwil]

I've just purchased a 2006 3.0Si convertible and it has this 10 speaker non DSP set up and I want to change out the original head unit for a new 1-din unit, probably Pioneer. @Spivey did you resolve the amplifier not working - was it something simple? Did you use a universal patch lead that matched the Z4 wiring to your head unit's?