I don't think anyone's done much with the side compartments in a coupe, and I'd appreciate your opinions on this.

My rear side storage compartments measure 6.5" deep, 7.5" wide, 14.5" long, approximately .41 cubic feet. Someone check my math please. Been out of school for many years. An 8" Kicker Solo-Baric (square) woofer will physically fit, and the specs call for a .33 - .75 cubic feet of sealed area. Kicker claims this square 8" woofer will move air equal to a conventional round 10."



To drive the sub, I'm looking at the Blaupunk digital amps, specifically the PA2100. They are physically small and the manufacturer claims they run cool, both important to me. I eventually want to have three of these (front, rear, sub) inside the center storage compartment, with no cooling fan.



So the idea is to have a square 8" Kicker Solo-Baric in the side compartment, driven by a Blaupunk PA2100 mounted in the center compartment. For now, I want to use the stock head unit and the stock speakers. Later, as resources become available, I want to replace the head unit, and add an additional two PA2100s (or equivalent) to drive new speaker sets front and back. The "Down the Road" finished system would include a new Head Unit, new front and rear speakers, the Solo-Baric sub (or two), and three of these digital amps in the rear center storage compartment powering front, rear, and sub(s).

A few questions...

1. Looking at the specs below, looks like the best way to wire the sub is as a "1 Channel Bridged Subwoofer."



This calls for a low level left and right signal from the head unit. Is there any way to get a non-fading low level left and right signal from the stock head unit? If not, I'll take the standard fading front left and right low level signal. I never use the fader anyway. Can anyone tell me where I can tap either of these signals?

2. The Solo-Baric is available as a Dual 2 Ohm or Dual 4 Ohm. The Dual 2 can be wired as a 1 or 4 ohm load. The Dual 4 can be wired as a 2 or 8 ohm load. It looks like the Blaupunk, used as a "1 Channel Bridged Subwoofer" wants to see a 4 ohm load.

If later I decide to add a second Solo-Baric to the other side storage compartment, I'd want to drive it from this same amp, which, when driving two subs, wants to see 2 ohm loads on each driver.



If I go with the single 2 Ohm driver now, I know I'll be fine as the amp will see 4 ohms. Later, if I add another sub, and connect both to this one amp as a "2 Channel Dual Subwoofer," the amp will only see 1 ohm instead of 2. Will this hurt the amp?

Thanks in advance!

Specs follow...






[Modified by John Silver, 6:14 AM 8/25/2001]

 

amp does not have enough power to drive the sub. Also I had a blaupunt amp same power as the you put on the board and it overheated and shut off all the time. :U. Those solo baric subs require alot of power to have them work right

 

These are the wiring diagrams for you -



Let me know if any q's

I think you will be ok with your setup.
Speed-racer

 

Thanks rzuff and speed.

Speed, I guess there isn't a non-fading low level signal, and from looking at the pin-outs you posted, it shouldn't matter if I tap the front or rear lines, right? Or are both the front and rear low outputs non-fading, full signals, that are processed later for filtering and fading?

Can I just connect some female RCA jacks to these lines? Is it ok to parallel these new RCA jacks with whatever their current load is?

 

Speed-Racer

Your C4 connector posting is not exactly correct. It is different from my 1999 GM manuals. It seems to be from another GM vehicle. Be sure not to attach to pin's 7 and 13. These are the floating returns for the outputs and inputs. Use 8, 14 or 15 for a return connection.

John Silver

There is no unfaded outputs from the HU. The Bose Signal Processor sums all four HU pre-amp outputs before feeding L&R sub signals to the two sub amps. The sub amps have an internal crossover.

 

This diagram was scanned in from 98 service manual.
Not sure what you mean, the connection matched what I found in the car.

Speed-Racer

 

John,

I did parallel the low level outputs. If you want to use the fronts and back without a fader then splice into the front Low Lev. outs. Splice into the rear outs, and fader works.

Speed-Racer

 

Speed-Racer

Your manual is wrong then. Won't be the first time. I bet this diagram was for another GM vehicle with a different version of the Delco HU used in the C5. For example, pin 7 is really the Audio Return-Conditioned-Common. This floating common is used by the psuedo-differential wiring scheme used in the C5. Your diagram says pin 7 is a center channel output.

The four low level pre-amp outputs should never to be connected together. There is a quad op-amp IC driving the four outputs through coupling capacitors. The Bose Signal Processor has input bias voltages, 6 volts, on all the wires going from it to the HU. You do not want to short these outputs or inputs together. The quad op-amp buffers the four outputs of the volume/tone/balance/fader control IC. There is no output before this IC.

 

The Blaupunkt amp won't cut it because it is not a hi-current design (hi-currents generally double ouput each time the impedance is halved), and because it is not 1-ohm stable. Look instead at phoenix gold, precision power or fosgate amps which can drive difficult loads, and have tri-y bridging (the ability to deliver two channels to speakers and bridge the terminals for sub output. You will need 200WPC@4 Ohms to get the job done.

Also keep in mind that a 10" Sub does not deliver that much output. You would need 2 minimum for decent bass impact and 2x 12" would be even better. The good news is that the square Solobarics live up to the rep in all respects. So consider 2 10"s, one in each corner. Your .41 CF VAS should be no problem, BUT be sure you do not need a rigid enclosure for proper output. The cargo pockets are floopy material. Also consider punching a hole in the bottom and running a traditional infinite baffle arrangement with a Cerwin-Vega or other hi-SPL sub.