Unamplified HU AMP question

**Gamer64** · 02-23-2007, 06:39 AM

Hey guys,

In my car i have a Bose Sound System. In the HU that comes with it is not a built in AMP. The AMP that belongs to the complete system is in th trunk (built away very nicely). So the speaker/audiowires from the HU go to the factory AMP, and from there to the speakers.

At this moment i have an AMP that is connected with a LowLevel Converter to one of the speakers in the back.

Is it possible to use one of the speaker/audio wires BEFORE it`s amplified instead of using a LowLevel Converter. At this moment when there is music playing with a rather high BPM the bass doesn`t sound synchronic with the bass from the other speakers.

I have drawn a nice little sketch from the situation.

**durwood** · 02-23-2007, 11:53 AM

Sure you could slap some RCA ends on the wires and connect directly into the amp without a LOC. However, some Bose systems are balanced I believe and there are a few ways around that. You could use one signal wire and the vehicle ground for each RCA end. Or you can find yourself some cheap balanced converters.

At this moment when there is music playing with a rather high BPM the bass doesn`t sound synchronic with the bass from the other speakers

That is another issue entirely.

Your sub is a much larger speaker and it will not react as fast as smaller speakers. Also, it could be a problem of the sub box not controlling the sub properly. Or, the time difference it takes for the lower frequencies to reach your ears is longer than what it takes from the other speakers. This can be corrected with tuning called "time alignment" or "time delay". Delay your other speakers slightly and the sub will blend better. Just some tips.

**scott_fx** · 02-23-2007, 12:23 PM

IIRC www.pacaudio.com and paripheral electronics make bose interfaces that do exactly what you are trying to do

**durwood** · 02-23-2007, 12:55 PM

close scott...

www.pac-audio.com

also...

www.soundgate.com
www.blitzsafe.com
www.peripheralelectronics.com

to name a few others..but then again these are LOC basically. Some BOSE sytems you can get away without them. It really depends on the car.

**Postman** · 02-23-2007, 12:56 PM

I know on late model Audi's it's already a low level signal going into the Bose amp, and I believe Acura's are the same, couldn't say on an Opel but it's worth a try. Remember if you do it like you're sketch and you do have low level preamp, you just halfed your voltage to the rear channels. Personally I would ditch the rear and run the sub and front stage to see how it sounds (assuming you do have the low level)

In regards to the sub, have you tried reversing the phase of the sub. You may be surprised how that can improve the sound.

**Postman** · 02-23-2007, 12:57 PM

Originally Posted by durwood

close scott...

www.pac-audio.com

to name a few others

Much better, I was going to say they need to get a more professional site!

**scott_fx** · 02-23-2007, 01:39 PM

lol

sorry about that

**Gamer64** · 02-23-2007, 07:21 PM

Awesome, thanx for all teh reply`s. I will try asap.

Also all the Bose equipemnt from PAC is for much newer cars for as far as ii could see. The Bose system in my car is nice because it`s integrated, but the expandability sux big time. I now use an FM Modulator (wired one) to get my audio from my CarPC to my HU but that`s also not a clear sound option. The other option i have is hacking in the CD Changer cable and hijack the audio wires. But then i always have the CD on my display with the tracks playing (which can`t be heared then).

**scott_fx** · 02-23-2007, 10:19 PM

i did the cdchanger hack for a while when i had my ipod and no computer. it works great. i'd go that route if you're not willing to drop the whole bose system

**Gamer64** · 02-24-2007, 11:27 AM

I think i will try that instead of the FM Modulator. Only i wish i could pause the cd changer or show a generic message on my display like " CD " or something. But i think that`s never gonna happen