74 Blaupunkt Bamberg / rear speakers question

[Hirth547]

Hi,

I have recently become the proud owner of a real nice and unmolested '74 Carrera CIS coupe. I am going through the car to ensure that everything is in good order. So far all mechanicals appear sound. Only had to replace a leaking fuel line.

A previous owner installed a later radio. I have taken it out and plan to replace it with a really nice period Bamberg I found. With regard to the installation I have a couple of questions:

- What kind of bracket was used to support the back of the radio to the bulkhead?
- In the excellent recent MFI book I have read that all Bamberg equipped radios came with the two speakers in the rear parcel shelf. As luck would have it my car has these. The problem is that I can not locate the speaker wires. Where would these be found?
- Was the center speaker used also? If so same question, where would one find the speaker wire?
- Was there a fixed position where the factory mounted the dictate microphone?

Many thanks for all your help.

Joris
The Netherlands

[Hirth547]

Not much luck so far. Attached some pictures.

The first one shows the radio installed, the second one the rear speakers which I believe are a factory set up. The third and forth show two unidentified wires under the dash.

Any help will be greatly appreciated

[rlane930]

- What kind of bracket was used to support the back of the radio to the bulkhead?

A: The Bamberg should have a front plate that attaches to the radio frame cutout and then a plastic frame on front.

- In the excellent recent MFI book I have read that all Bamberg equipped radios came with the two speakers in the rear parcel shelf. As luck would have it my car has these. The problem is that I can not locate the speaker wires. Where would these be found?

A: Your car would be very rare with a Bamberg with speakers in the rear parcel shelf. I've searched for years online trying to find photos of '74/75 equipped with one to no avail. The top of the rear shelf should be fiberglass and the speaker wires were routed to the sides of the rear shelf then to the front of the car.

- Was the center speaker used also? If so same question, where would one find the speaker wire?

A: The dash pad center speaker should be wired in parallel to the left of right speaker connection. It was wired to the right speaker in my 1975 Turbo. If your car has the original wire bundle, look for the parallel connection, otherwise, you can just do-it-your-self when you wire the center speaker. Is your dash pad speaker still present/wired? If your speaker is gone, the wire may still be there and it is routed through a hole in the bulkhead to a wire connection close to the radio in the cabin.

- Was there a fixed position where the factory mounted the dictate microphone?

A: not sure about the dictate microphone. I've never seen a factory Bamberg in a 1974-1975 911 or 1975 Turbo so not sure of the setup. In the 1976 Turbo, the microphone was in the left pocket and for the 1977 Turbo, mounted in the center console.

The rear parcel shelf is easy to remove and it would be interesting to see photos of yours. My 1975 Turbo has an inked production number and yours may also have one since it was rarely optioned on a 1974/1975 911s/Carreras.

[Hirth547]

Hi Rlane,

Thanks so much for responding. I loosened the rear parcel shelf and found the two speakers. The material is exactly the same as the rest of the interior. I could not find a production number. The wiring feeds off to the passenger side and is black on the one and green on the other. It is the exact wiring shown in my above picture.

I went ahead and connected it to the radio. The radio i brand new out of the Blaupunkt box. It fired right up but the volume is very low. I have to turn the volume to max to hear something. The center dash speaker works. I am not getting any sound from the rear parcel shelf speakers. Should there be an additional loom somewhere for the rear speakers or were they wired in parallel with the dash speaker?

Many thanks,

Joris

[rlane930]

The left and right rear parcel shelf speakers should connect to the inputs on the Bamberg (L and R). The dash pad center speaker is connected in parallel to the L or R speaker wires. Do you have door speakers as well? Are you sure the rear speakers are still good? You can try an ohm meter to make sure they are still good to go (original Blaupunkt's are usually 4 ohm).

[group911@aol.co]

Can you take a picture of the parcel shelf from the front? I think the raised shelves had speakers and the flat ones didn't. Your speaker sound holes that are punched in the vinyl don't look like the factory pattern.
The speaker wires typically were routed along the tunnel or along the outer seat rails, then up under the seat bottom carpet and then come out somewhere behind the seat tops.

[rlane930]

The speaker pattern is correct for '75-76 (same pattern in my '75 Turbo). It was probably the same pattern in 1974 but as I mentioned before, I've never seen a speaker parcel shelf in a 1974 model year 911. It changed to an oval pattern in 1977.

[Hirth547]

Hi,

Attached a picture of my rear shelf. Also attached a side shot of the power pack showing how I have the speakers wired right now. Excuse the non Blaupunkt connectors, still looking for some original ones.

The only wires I could find under the dash and identify as speaker wires are the ones for the door speakers (which are not original to the car and installed later) and the black/green wire coming through the bulkhead. These are the speaker wires I have currently hooked up and appear to be for the dash speaker. What is unclear to me, excuse my ignorance, is if the rear speakers were wired in with the dash speaker or have their own distinct wires which connect to the radio.

[Hirth547]

I got the COA from Porsche yesterday. The Bamberg was ordered wit the car which explains the speakers in the rear parcel shelf. Still having a problem getting any volume out of the radio. Any ideas out there?

[rlane930]

If you have the rear shelf out, connect new test speaker wires to the rear speakers directly to the radio. That way you will know if the old speaker wires may be grounded, etc. The wiring is pretty straightforward on the Bamberg, left/right speaker connection and the dash pad speaker is wired in parallel to the left/right.

[speedster911]

Looking for bamberg radio for my 74- please PM if you have one for sale. Thank you

[speedster911]

Originally Posted by Hirth547

Not much luck so far. Attached some pictures.

The first one shows the radio installed, the second one the rear speakers which I believe are a factory set up. The third and forth show two unidentified wires under the dash.

Any help will be greatly appreciated

Hirth,

Where did you end up installing your Micraphone?