Soundblaster not pushing my subs...

**3onDubs** · 11-17-2005, 02:14 PM

I just completed my carPC install the other day and since then i've been trying to get my sound ironed down....i've got a soundblaster running 5.1 going to two amps (a 4-channel for my speakers and a 2-channel for my subs)

I've got three 3.5mm to dual rca converters that I got from radio shack plugged into my sound card. The one runs the front speakers, the second one runs the rear speakers, and the third one running the subs.

I know that the third 3.5 mm port is supposed to be for center/sub....so you have to leave one of the RCA jacks unplugged and only use the sub channel...I checked both channels and am sure that I am using the correct plug (subs work at a really low level on the correct one and dont work at all on the other one)....I have a y splitter running into this rca jack that I plugged the left and right channel of my sub rca wire into.

The problem is this...the subs barely bump at all...i've messed with the sound card's software, but can't figure it out....the subwoofer level is at max and i've tuned the equalizer. I can hear the subs working, but probably at 10% of what they used to be when I had my HU running them.

Could this be because my headunit put out more power for the sub channel? Or is it that my amp needs to be retuned to accomodate the change from HU to soundcard?

**StrataG** · 11-17-2005, 02:26 PM

Most definately you will need to turn up your gains on the amp. The sound card is likely putting out 1/10 of the voltage that your headunit was.

**3onDubs** · 11-17-2005, 02:33 PM

Originally Posted by StrataG

Most definately you will need to turn up your gains on the amp. The sound card is likely putting out 1/10 of the voltage that your headunit was.

Thanks...I will definitely try turning this up and see what happens...one more question, does this apply to the amp powering my inside speakers as well? They seem to sound fine to me, but I'm no expert...

**WxGuy1** · 11-18-2005, 01:15 AM

If they sound fine to you, why mess with it? IF you want to be sure, you should set your gains with a multimeter as outlined on various websites (you can Google it). However, if it sounds fine to you, do you need to mess with it?

**3onDubs** · 11-18-2005, 11:39 AM

Originally Posted by WxGuy1

If they sound fine to you, why mess with it? IF you want to be sure, you should set your gains with a multimeter as outlined on various websites (you can Google it). However, if it sounds fine to you, do you need to mess with it?

Just in case...ya know...a real audiophile does get in my car and notice that im not getting the cleanest possible sound out of my setup...also, it might sound fine to me, but it could probably be better, and I wouldn't know that unless I hear it get better...ok, I just confused myself...but I'll definitely try using a multimeter to set them.

**StrataG** · 11-18-2005, 11:54 AM

Using a multimeter is great and all, but your ear should be the final test. I personally don't bother with a multimeter because I've never had the greatest results from it. I always just set my volume to 75-80% and then tune my gains with my ear.

**3onDubs** · 11-18-2005, 05:57 PM

I was looking into some other options on improving my sound quality and was thinking about either going the DSP route or gettting a line driver or both.

If I add a DSP like the Panasonic CY-AC300 to replace my soundcard and use the optical out on my via M10K, will this improve my sound?

I know that some people have suggested using line drivers...does the Panasonic DSP have this built into it?

If not, would I just be better off with a line driver?

**TheLandYacht** · 11-20-2005, 03:04 PM

Originally Posted by StrataG

Most definately you will need to turn up your gains on the amp. The sound card is likely putting out 1/10 of the voltage that your headunit was.

Or the other solution to this is to add what's called a "line driver". You can get a fancy in-dash one or a fairly plain one that goes inline and can be hidden away.

The purpose of these is to take the fairly puny output of whatever your source is and bump up the voltage to something more like what your amplifier is expecting to see.

**XxAndyxX** · 11-20-2005, 05:38 PM

Originally Posted by StrataG

Using a multimeter is great and all, but your ear should be the final test. I personally don't bother with a multimeter because I've never had the greatest results from it. I always just set my volume to 75-80% and then tune my gains with my ear.

^I don't recommend doing this. Use a multimeter because if you try to do it by ear you could potentially clip your amps without knowing it, and dammage your equipment. First, tune it by a DMM to see what the max your gains can be at before clipping, then tune it by ear making sure you don't go past the maximum output you just set.

**StrataG** · 11-20-2005, 05:47 PM

I never said that it is bad to use a multimeter, I just said when I have, I wasn't happy with the results. I've never had an amp/speaker blow on me, and never had any audible distortion in my systems. Once I tune it at 75-80%, I put it up all the way to see if I hear any bad clipping. If I do, I back down the amps a bit more. Obviously tuning to 75-80% will yield some clipping at full volume, but if I hear bad clipping at 100% I turn down the gains a bit more. The multimeter route has always yielded higher gain settings than I've ever set by ear. Maybe I'm overly cautious with my settings by ear, but I'd rather be anyway.