Zapco Z-series B - Manual (Page 5)

Gain Setting
Matching Your Components for Best Sound
Proper gain setting is one of the most important factors in setting up a stereo
system.
Unfortunately, gain setting is quite often done wrong. Turning up the
gain of an amp is the very last thing you should ever do to a system.
An amplifier is a step up transformer. Period. Any signal you put in is boosted by a
fixed factor
, whether it's music, hiss, or any other noise. A large number of
noise problems are simply a matter of improper gain settings. The goal of gain
setting is to achieve the maximum amount of musical output from the amplifier
while getting the least amount of hiss or noise from the system. Your Z-Series
amplifier accepts an extremely wide range of input levels. As little as .5
volts
on the RCAs to as much as 8 volts. The basic gain setting is very simple and
requires no special tools. Whether you have a simple system with a deck and an
amp, or a system with a deck, line driver, equalizer, crossover, and amp, the
procedure is always the same. First, hook up the system with all gain controls at
minimum (turn the gain pot fully counter-clockwise with a small screwdriver).
Then turn on the head unit and turn up the volume. If you achieve clean sound,
and, more volume than you want, you don’t need to make any adjustments.
However, if you turn up the volume and begin to hear distorted sound before it
becomes loud, you are clipping (distorting) the deck (probably a little over ¾
volume). Turn the deck down just enough to hear clean sound again, and then
move to the next component in your system. With the deck playing at “maximum
clean volume” adjust the gain of the next component to its “maximum clean
volume”. If you adjust your gains this way, always starting at the head unit and
working down the line to the amplifier, you will get the most performance out of
your amplifier(s) with the least amount of unwanted distortion and noise.
Presenting
The Zapco Z-Series Amplifiers
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