The gain (or input sensetivity) control is designed to match the inputs of your amplifier to the outputs of your head unit. This is easy to accomplish with a test tone CD and a digital multimeter.
We know how many watts the amplifier is designed to produce. We know the impedance it needs to produce this wattage. Measuring voltage is the easiest way to measure the voltage an amplifier is producing.
JL Audio provides an interactive tutorial, though they only provide a "target voltage" for their amplifiers. (Can you blame them?) This page will tell you your amplifer's target voltage, regardless of brand.
Find out your amplifier's target voltage by filling in the blanks and clicking the button:
My amplifier is rated for watts into ohms.
Please do not try to fool your amplifier into producing more wattage than it was designed to produce. This will result in "clipping" and damage to your speakers or the amplifier itself.
- Disconnect speakers.
- Turn your gain/input sensetivity all the way down. Turn off bass boost and any crossovers.
- Turn on your head unit. Set the volume control to 3/4 of full. Set all equalization and bass/treble controls to zero. Turn off loudness and BBE processing.
- Probe your amplifier's outputs.
- Insert your tone CD. Select a tone within your amplifier's playing range.
- Play your selected tone and adjust the gain until you reach your target voltage.
- Reconnect your speakers and verify proper operation. Set crossovers and adjust levels for proper tonal balance.
Ask questions in our amplifier forum.