Correctly setting the Gain controls on your amplifier is easy if you have some signal test discs and an oscilloscope! But, if you don't happen to have those available, then you may have to do some common-sense guesswork to "dial-in" your amplifier.
The gain control is NOT a volume control! The gain adjustment (or control) is a level-matching potentiometer that matches the amplifier pre-amp inputs with the pre-amp outputs of the electronic component used IN FRONT of the amplifier. The electronic component(s) could be a source unit, an equalizer or a crossover. You can find out the electronic component's pre-amp output voltage in the owner's manual, as most manufacturers know this is beneficial in order to dial-in your level settings for your system.
Essentially you're telling the amp how much signal you're putting into it so the it's output devices will reproduce the signal cleanly. If you have the gain set too high (gain overlap,) the amp will make full power right away, and you'll have problems with distortion and excessive "clipping". If the gain is set too low (gain underlap,) the amp may still make full power, but it might not sound as loud as it should, and you'll think you aren't getting much "volume."
You change the amplifier's pre-amp sensitivity by adjusting the gain control clockwise (more sensitive for low-power sources like 1-Volt) or counter-clockwise (less sensitive for high-powered sources like 4-Volts.) It is nearly impossible to have "too hot" of an input signal into the amplifier. For sources that have very high output voltages (example: 9V) you'll keep the amplifier gain settings adjusted lower than traditional lower powered sources.
Since most of the time, there are not "indicators" or markings on the side of the amp to indicate gain levels for specific input voltages, you will have to do a little "educated guessing" to set the controls up correctly. An oscilloscope's signal-measuring capabilities would come in handy, as you could read the output levels of the amplifier while playing test tones (like a 1KHz tone) to determine at what point your amplifier "clips", and that's where you stop turning up the gain control.
If you don't have any of this cool stuff, then you'll have to assume the gain control is like a progressive-gain dial that becomes more sensitive as you turn it up (clockwise).
- After setting the system up, turn off the system.
- Adjust all amplifier gain controls to minimum.
- Adjust the main volume control on the system 3/4 way up.
- Increase the amplifier gain controls until it's at the maximum audio level you'll ever listen to the system.
***While these suggestions are by no means 100% accurate, they will work fine most of the time. When in doubt, have a professional double-check your work.***
As far as the Bass control, setting it correctly is a matter of both personal preference and the type of enclosure you are using for your speakers. If you are using your amplifier with a speaker (or set of speakers) that are loaded into sealed enclosures, then generally we recommend setting your amplifier's Bass control no higher than 1/4 of the way up. If you are using a ported enclosure for your speaker(s), then we generally recommend setting the Bass control no higher then 3/4 of the way up. Because the Bass control is really an equalizer, you should not use it if you already have an EQ hooked up to your system (unless your EQ does not cover frequencies below about 70Hz).
***Note: If you're unsure of the best way to set up the gains or bass controls on your amplifier, we recommend you seek assistance from a professional and the advice of your local Electronics dealer. They have the knowledge and equipment necessary to be able to set your gear up right!***
