Bose Subwoofer Retrofit

[gavins]

I have a 2006 C2 with the standard (i.e. NOT the BOSE) sound system.

I have found the sound system to be inadequate and a couple of months ago fitted a pair of Blaupunkt THB210a powered subwoofers behind the rear seats, in the space where the Bose subwoofer box (if fitted) goes. The sound signals are taken off the rear speakers, and I tapped into the high amperage power circuit driving the electric sunroof. This has worked VERY well indeed and I recommend this solution to anyone looking for an easy and cheap (US$250) sound upgrade. However, the setup is very visible through the rear window and not particularly neat-looking and I have been looking to buy a used BOSE rear subwoofer box (part 997.645.564.00), as fitted to the 997 with the Bose sound system. Last week I finally located and bought one from a salvage yard. I intend to fit this behind the rear seats and hook it up to an external subwoofer amplifier. I was expecting a simple hookup to left and right rear speakers (as I currently do with the Blaupunkt powered subwoofers) but the Bose subwoofer box has 7 (seven) wires on the connector block. These are blue, red, white/black, brown, black/red, yellow and brown/yellow. This is NOT what i was expecting. Does anyone have any idea what all these connections are for? I have opened up the subwoofer box (easy as there are 24 torx bolts holding the cover on) and found inside a small electrical unit resembling a crossover. It has a connector with 11 cables, 7 of which come from the external connector block, plus two to each of the two internal subwoofer speaker units. I attach several photgraphs showing the external connector block, the internal crossover (?) unit, the speakers and the general layout. As mentioned, the plan is to hook the subwoofer assembly up to an external subwoofer amplifier. I guess i can bypass the internal crossover, if this is indeed what it is, but it would be helpful if i knew exactly what the function of the unit is. I doubt it is an amplifier as it is quite small, measuring about four inches by four inches by two inches. Any help, advice gratefully received!

Edited September 22, 2009 by gavins

[jwat]

The box you see is a small bose amp. Many folks have sent a signal from their new head units to this amp with mixed results. I am in the process of doing just that but will likely put true subs run off an external amp at some point. If you have an amp already I would reccomend you bypass the small bose amp all together. Read here for an idea how to do this http://www.planetporsche.net/cayman-boxste...html#post385565

John W

[gavins]

Hard to believe that that little built-in BOSE amp is powerful enough to drive the subs, and also I have no idea which of the seven input wires to use if i do try to use the little built-in BOSE amp. But the good news is that there is more than enough space in the subwoofer box to fit a Blaupunkt compact subwoofer, although I have no idea what impedance the BOSE subwoofer speakers are.

[gavins]

Could someone please help in advising how to use the stock Bose subwoofer amplifier (100WSR) that is fitted inside the 997 rear shelf subwoofer box WITHOUT the complete Bose sound system. In other words i want to hook the Bose subwoofer amp up to existing speaker outputs.

The terminals on the Bose subwoofer amp are:

GND (connected to the same pin as the other GND)

SWB+

IN+2 (empty)

IN+1

IN-1

VCC (connected to the same pin as the other VCC)

SPKR+ (goes to subwoofer 1+)

SPKR- (goes to subwoofer 1-)

GND (connected to the same pin as the other GND)

VCC (connected to the same pin as the other VCC)

SPKR+ (goes to subwoofer 2+)

SPKR- (goes to subwoofer 2-)

So, there are 12 pins on the subwoofer amp, one of which is not connected. Of the 11 pins, 2 are connected to another 2. And four go to the two loudspeakers. This makes a total of 5 connectors on the cable that plugs into the car's sound system. These 5 are GND, SWB+, IN+1, IN-2, and VCC. I would gues that two are power, one is right, one is left, and one is sound common. Is this right and, if so, which is which?

[355bhp]

I have found the sound system to be inadequate and a couple of months ago fitted a pair of Blaupunkt THB210a powered subwoofers behind the rear seats, in the space where the Bose subwoofer box (if fitted) goes.

How did you remove the carpeted cover to get to the rear speakers? Thanks.

[gavins]

Hi Rick, if you are talking about the two rear side=panel speakers, I simply threaded speaker cable through the space between the rear side panel and the base of the rear shelp (ie the lower section, on which the rear subwoofer box sits). If you pop out the rear side panel speakers (use a credit card around the edge of the cover) and then use a torx to unscrew the speaker mounting from the cutout, you can reach inside and grab the speaker cable that you are feeding into the space. Hope this all makes sense - its difficult to explain in words...easy when you see how! BTW, I eventually fitted a small Blaupunkt amplifier inside the sub woofer box instead of the stock Bose unit, which i couldnt figure out how to connect. I have posted a separate thread on how I did all of this and i works really well.

[355bhp]

Hi Rick, if you are talking about the two rear side=panel speakers, I simply threaded speaker cable through the space between the rear side panel and the base of the rear shelp (ie the lower section, on which the rear subwoofer box sits). If you pop out the rear side panel speakers (use a credit card around the edge of the cover) and then use a torx to unscrew the speaker mounting from the cutout, you can reach inside and grab the speaker cable that you are feeding into the space.

Thanks for the reply. Actually, I'm talking about the subwoofer box itself. And it looks like I'd first have to remove the small 3X5" speakers (with the Bose logos) from the carpeted box. Would I pry those loose using the credit card? Apparently, there's something loose and rattling around inside the plastic subwoofer housing, and I wanna get at it.

[gavins]

The speakers inside the carpeted subwoofer box simply unscrew. The fun bit is opening up the box itself, which is in two halves, and held together i swear with about 1,000 screws around the edge! you will need a torx screwdriver with a long shank and lots of patience! Once you open up the subwoofer box its easy to see if there's anything inside that's rattling around. But before you ipen up the subwoofer box, check to see if the trim bezels around the speaker vent outlets are loose. Mine were.

[355bhp]

The speakers inside the carpeted subwoofer box simply unscrew. The fun bit is opening up the box itself, which is in two halves, and held together i swear with about 1,000 screws around the edge! you will need a torx screwdriver with a long shank and lots of patience! Once you open up the subwoofer box its easy to see if there's anything inside that's rattling around. But before you ipen up the subwoofer box, check to see if the trim bezels around the speaker vent outlets are loose. Mine were.

Gavins, one more thing: did you use the speaker cable as an aid to lift and/or pull the the box from the lower shelf? And thank you for your infinite patience with me!

[PAULSPEED]

Remove the plastic shroulds from the speaker box holes. You will

then see the torq screws that hold the box in.

Paul

[Jayson hobbs]

Need wire digram to hook this Bose amp so I can

[David LAGEYRE]

hello Gavins.... I'm David, I'm french... i don't speak very well so sorry ! Google translate

I have been looking for 1 year for information to connect a subwoofer as well. I am in a porsche 997 mk2 equipped with the ASK system so with the amplifier under the seat... I would like to add a rear subwoofer like you... if I understood correctly you took the right and left outputs of the mids rear wing panels? then extended the cables to connect them to the inputs of the new amplifier? so as if we connect RCA cables to the inputs of the amplifier? has the + supply been taken from the arrival of the sunroof? and the mass? on the other hand I do not understand there is no connection with the PCM 3? Could you make me a diagram of your installation because I do not understand everything ... thank you for your help
If you wish, here is my email lageyredavid@yahoo.fr if you prefere.