zapco DC-352, Owner'S Manual

Gain Setting

Matching Your Components for Best Sound

Proper gain setting is one of the most important factors in setting up a stereo

system. At the same time, gain setting is most 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. Music, hiss, or any other noise, it doesn’t matter. 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

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 DC-Series

                   Sound Quality / Integration Amplifiers

-17-

Keep the amplifier out of the engine compartment and other locations that

     may cause excessive heat or moisture.

     Make sure your ground point is at the frame or a chassis point with direct

     frame contact. Note: the "quiet metal" on many new cars make body

     panels very bad ground points, so always try to use the frame.

     Do not mount the amplifier to a subwoofer enclosure or any other place

     that may have excessive vibration!