CarPC, Stock HU amp install question

**Kimota** · 05-12-2007, 12:03 PM

Hello,

I have installed a CarPC in my 2005 Mazda RX8 and am using the Car2PC-MAZ for the aux in with the Factory HU/6 CD changer to get PC sound to the HU(its all working great).

My question is I would like to install 2 amps, a sub box with 2 X 10" woofers, 2 x 6X9 speakers as well as a set component of speakers. I plan on using 2 Rockford Fosgate amps a Punch P450.2 to drive the subwoofers and a Punch P450.4 to drive the 2 X 6x9's and the component speakers. Would it be possible to get PC sound as well as sound from the Factory HU/6 CD changer to work with the amps?

I have read a thread on "HOW TO: Get sound from PC to Car Stereo / Amp" this will get the PC sound to amp but will this get Factory HU/ 6 CD changer sound to the amps as well?

Note I'm using an Aopen i945GTt motherboard with onboard 5.1 surround sound.

Any input would be greatly appreciated

Thanks

**lbridges** · 05-12-2007, 07:33 PM

I must be missing something in your question. If the PC to HU works, and you plan to keep the HU, why not just go from the HU to the amps?

**slammedteg91** · 05-13-2007, 08:47 AM

Ok I understand your question (I just wrote a whole response then realized what you really are trying to do lol)! The amps you want don't have "high level inputs". This is what you need.

In most setups (that use aftermarket head units), the signal is delivered from the head unit to the amp by RCA cables, these are "low level". Some amps have "high level inputs" built in, which means you can run speaker wire from the head unit to the amp if it doesn't have RCA outputs, stock head units don't. (front right + on HU to front right + on amp, etc for all 8 wires (4 channels + and -). Hope I didn't confuse you lol. So you need an adapter (like this: http://www.crutchfield.com/S-wHW8LCV...evel&i=142SLC4) to convert your high level inputs to low level (basically converting speaker wire to RCA - and NO you cant just splice, you need the converter).

To wire up the subwoofer amp, you will see that the 4 channel amp has 6 RCA plugs on it. 4 are inputs (from the converter), and 2 are outputs. Just run RCAs from the output on the 4 channel amp to the input on the 2 channel amp. This setup should do exactly what you need it to do.

As far as PC sound goes. Basically, whatever sound comes out of your speakers now will still come out the same, it's just going through the amps first, if that makes sense. With this setup, your not messing with the inputs of the radio (examples: AM/FM radio, CD changer, PC, etc), your working on the outputs (speakers). Good luck and any questions let me know!

**Kimota** · 05-13-2007, 12:47 PM

Hey slammedteg91

Thanks so much for the info, sorry if I didnt explain myself too clearly I'm new to car audio.

I'll definitly look into picking up the Scosche SLC4 just have find out what wires to tap for my car.

Thanks again

**slammedteg91** · 05-13-2007, 02:14 PM

LF Speaker + = red
LF Speaker - = white
RF Speaker + = white/red
RF Speaker - = yellow/red
LR Speaker + = purple
LR Speaker -= pink
RR Speaker + = white/blue
RR Speaker - = black/blue

Thats from an 06 RX8, I couldn't find 05 (or 04), maybe check a service manual if these colors are wrong. Let me know if they are, I can look harder lol, good luck!

Another question, does your car have an external amp (maybe under one of the seats)? If so, that converter might not even work for you (unless you use the speaker wires AFTER the amp), because the wires going INTO the amp would be low-level (like RCA, but because its factory it is just normal wire).

**Kimota** · 05-13-2007, 03:34 PM

Thanks again man, your suggestion for the Scosche SLC4 seems to have been the missing link I was looking for.

I've been on the RX8 Club site for a while and noticed that people have been keep the stock HU and using aftermarket amps and speakers but didn't understand how. Thanks to you I see they are using an LOC to do this.

Ohh my car has the factory Bose system and does have the factory amp in the trunk. I'll dig a little deeper on the RX8 club site now that I know what I'm looking for.

Thanks for shedding some much needed light on the subject

**slammedteg91** · 05-14-2007, 09:59 AM

Ok, thats really easy then. All those wire colors I gave you should be in the trunk. Just take out the factory amp, wire up the scosche adapter, and hook up the new one (I'd run a new power wire from the battery to the new amp of course) and you should be good to go!