Setting gains with amp and outboard soundcard

Quack · 06-08-2006, 12:08 PM

I'm looking for a method to set the gains on my m-audio USB MobilePre soundcard and Alpine MRV-F450 amplifier. I would love to find something like JL Audio's gain tutorial that basically spells out what voltage to shoot for at the amp's speaker outputs. Can't find anything like this for Alpine though...and the extra component in the MobilePre soundcard adds a level of complexity.

I'm not using a headunit...rather I'm controlling everything including volume from FrodoPlayer on my touchscreen. Any help would be appreciated!

RedGTiVR6 · 06-08-2006, 01:26 PM

that's a pretty damn good tutorial, very nice find!

on another note, it's a bit too precise for most people, and unless you are looking to do some serious competing or are just super anal retentive, it's not really necessary.

Set the levels on the sound card at something reasonable, and then tune the gain on your amp like you would any other system.

If you're unsure about how to do that, check here:

http://www.350z-tech.com/zwiki/Tutor...plifier_Tuning

Eternalodyssey · 06-10-2006, 05:22 AM

Another good idea could be to make friends with someone at a car stereo installation store and find out what levels they are setting systems they are installing. Another good option is to possibly borrow a decibel meter and measure the decibels at at each speaker to help maintain sound staging you would be surprised how many products can differ in the level of output they produce. But the biggest suggestion would be to ask around at an installation place if possible. I have found most people are friendly enough to give you advice to keep you from starting your car on fire.

Quack · 06-10-2006, 08:33 AM

Red - Thanks for that link. Assuming those are sine wave files at 60 Hz and 1000 Hz, I could actually measure the signal through my RTA software's oscilliscope mode to visually see when the signal distorts. Then I've got visual and audible confirmation of where everything breaks up. Oh fun...a good reason to break out the RTA!!

Quote: Originally Posted by Red GTi VR6

that's a pretty damn good tutorial, very nice find!

on another note, it's a bit too precise for most people, and unless you are looking to do some serious competing or are just super anal retentive, it's not really necessary.

Set the levels on the sound card at something reasonable, and then tune the gain on your amp like you would any other system.

If you're unsure about how to do that, check here:

http://www.350z-tech.com/zwiki/Tutor...plifier_Tuning

RedGTiVR6 · 06-10-2006, 05:03 PM

heh - enjoy!