Help needed with subwoofer/amp/carpc install

**Toxic0n** · 07-17-2009, 01:44 AM

Hi,
I've got a CarPC running perfectly on this motherboard
http://www.avalue.com.tw/products/ECM-3611.cfm

It's got onboard AC97 audio. I have a 3.5mm wire running to the headunint - everything sounds great.
I am trying to add a subwoofer to the system. I've got a 10" Pioneer single coil sub - 4Ohm, 700W max, 350W RMS
I have an Xtant A2002 amplifier.

http://www.xtant.com/archives/html/t...02_4004Man.pdf

I used a 3.5mm Y-splitter + 3.5mm to RCA converter to direct the sound to both my headunit and the amp. I then hooked up the amp to the sub in bridged mode but I am not getting any sound. The amp is set to Low Pass, Balanced Input Off. Any ideas?

**jake789** · 07-17-2009, 01:50 AM

You should wire the pc to the aux in of the deck, then use the sub output of the deck to the amp.

**Toxic0n** · 07-17-2009, 02:00 AM

the deck does not have a sub out. Is there any other way around? I thought this was supposed to work this way without any issues...

**Toxic0n** · 07-17-2009, 02:14 AM

One more thing, when I unplug the amp/sub from the Y splitter, it seems the sound coming from my speakers actually gets louder. No idea why.

**almera** · 07-17-2009, 02:28 AM

How about wiring the pc to the aux in of the deck, then use the speaker output of the deck to the amp.

From your amplifier owners manual;

Optional Performance Upgrades
High Level Adapter (HLA)
This adapter allows you to connect a source unit with speaker level outputs to your Xtant amplifier.

**Toxic0n** · 07-17-2009, 02:46 AM

That might be a bit difficult to find. So basically there is no way to go from speaker out on my sound card to an amp? I've seen others to it on this site without any problems

**pancit175** · 07-17-2009, 06:02 AM

The most important part of your diagram that I'm not seeing is if you connected the remote out from the deck to the amp. And is the amp turning on? Have you checked your +12v and GND connections to see if its getting the correct power as well? Is the Fuse in?

Originally Posted by almera

How about wiring the pc to the aux in of the deck, then use the speaker output of the deck to the amp.

From your amplifier owners manual;

Optional Performance Upgrades
High Level Adapter (HLA)
This adapter allows you to connect a source unit with speaker level outputs to your Xtant amplifier.

This is otherwise known as a Line Out Converter (LOC) and can be found nearly everywhere that sells mobile audio electronics

Originally Posted by Toxic0n

That might be a bit difficult to find. So basically there is no way to go from speaker out on my sound card to an amp? I've seen others to it on this site without any problems

There would be no other way I would recommend doing this considering your current setup. Otherwise you would get uneven signals going to the amp anytime you increase the volume from the PC or the Headunit.

**bratnetwork** · 07-17-2009, 08:52 AM

Hook an ipod directly to the amps rca inputs through the head phones port and turn the amp on and play music. turnthe volume up and down on the ipod. if still no sound out of the sub then its and amp/sub issue not the wiring or pc. Also check the gain setting on the amp. Most amps I've worked with have either a gain adjustment or level in adjustment that will affect the over all volume of the output of the amp.

**Toxic0n** · 07-17-2009, 09:19 AM

The amp is turning on - the red LED on it is on. I have the remote wire connected to the remote on lead on the M1-ATX power supply. I hooked up my iPhone and played music on it and could not hear anything from the sub. I tried turning up the gain and the bass boost. Looks like a amp/sub wiring issue? I just don't see what could be wrong. Do I have it bridged correctly?
Here's some pics of how it's wired up:

http://img20.imageshack.us/img20/4998/dsc05674k.jpg
http://img268.imageshack.us/img268/2492/dsc05675d.jpg
http://img268.imageshack.us/img268/4880/dsc05677r.jpg

Regarding the uneven volume issue, if I get this working, can I hook it up to the line out on my sound card? The volume for that is controlled independently from the master volume, is it not?

**soundman98** · 07-17-2009, 09:44 AM

the best way to connect it would be to use the head unit speaker outputs. using just rca cable from the pc would work, only if you were amplifying all of your speakers.

by setting it up the way you have, you will now have 2 volume adjustments--the one on the radio--for the main speakers, and on the computer, the one for the main speakers, and sub. if you ever decide to listen to the radio, or a cd/tape in the radio, the sub will not work.

being that you did not get any sound w/ the ipod, i will have to say that you are going to need to test the speaker leads from where they are connected at the amp, unplug them, and test them w/ a ohm meter to double check that you have the proper ohm reading for the sub, if that is good, then it could be a bad ground, or a defective amp.