Tools you need......
1. A multimeter that can display AC voltage
2. A tone cd with tones in the ranges you play....
I usually use 40Hz for sub channels and 800Hz - 1400Hz or so for my mids and highs. If you have your highs on a channel, you can use 18000Hz+ for them.
Figure out what voltage you need to have on each channel using the manf. specs:
Ohms law regarding voltage
volts = sq.root of watts x ohms
So if your amp is rated to 200 watts @ 2 ohms, then you want to have 20 volts leaving the speaker terminals.
200x2=400.....sq root of 400 = 20 volts......
To setup......
1a. Turn the amp gain all the way down.
1. Put the tone cd in and set it to loop on the track, unless you have a length track.
2. Unplug at least one side of your speaker output.
3. Turn the headunit up to about 3/4 volume, this is a safe zone for most head units.....higher will result in the HU clipping the signal before it even gets to the amp.
4. Take a reading on the amp terminals in volts.....
5. Adjust the gain until it falls into the previously configured formula.
Repeat for the other inputs.
Once it is all done, hook all the speakers back up , and then adjust the levels for the speakers playing to loudly by turning them down....you do not want to turn up any gains as they are already at max.