How to Adjust Balance on JL 300/4 Amp [Archive]

Matt Ion

September 19th 06, 04:59 AM

Jason Danziger wrote:
> How do I adjust the balance on a JL Audio 300/4 amp? I know I am supposed
> to play with the input sensitivity but how do I know how much and which way
> to put it?

If by "balance" you mean the relative levels between front and rear, what I'd
probably do is set the front input level first to what's "appropriate", then
adjust the rear input to the "proper" level to match.

Of course, what's "proper" is whatever sounds best to YOUR ears.

> Also I get a bit of hissing at higher volumes. Should I increase the volume
> at the HU and lower the gain at the amp?

The more you turn up the gain on the amp, the more you boost the signal AND
whatever noise is produced by the HU and picked up in the cables.

The method I usually use is to turn the amp gain down low, then turn the deck up
until the sound starts to distort: this is the level where you're either
overdriving the deck's output, or clipping the amp's input. Back it off a hair
from there, and you'll have the hottest signal your deck can provide cleanly.

Leaving the deck volume where it is, then start brining up the input gain on the
amp's front channel, again, until you start getting distortion/clipping,
indicating either the amp's maximum clean output, or the speakers' max handling.

Finally, bring up the rear input level to about the same point as the front, and
sit in the car as you would when driving normally (doors, trunk, windows
closed). If necessary, adjust the rear level to balance out with the front.
Theoretically, you want the sound to appear to be coming from directly in front
of you, so the rear speakers would normally be a bit lower than the fronts, but
once again, unless you're building a competition system, think more about what
sounds good TO YOU.

Hope that helps....