Rockville DB Marine Series, Owner'S Manual

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17
PROBLEM
Amp is clipping
Distortion, background noise,
crackling, or hissing in the
speakers
3. If the gain setting is too high, this can cause the amp to clip. The proper way to set your gain is to turn
your receiver volume to 75% of the max, and then slowly turn your gain up. The second you hear any
slight distortion, turn it down one notch and leave it at that setting. Amps are not meant to be played with
the gain up to the max. If this is the case, lower your gain slowly until you hear the amplifier stop clipping.
4. A poor ground cable connection can cause your amp to clip because improper power is getting to the
amp. Check your ground connection and make sure that the cable is securely tightened.
5. A very common cause of amplifier clipping is power and ground wire that is too thin of a gauge size for
the amplifier. Determine the proper wire gauge necessary and replace existing wires.
6. If using multiple devices that all have a volume control (such as an equalizer or processor, receiver, and
the amp) then you would need to lower 1 or 2 of those devices to stop the amp from clipping.
1. First check to see how your wires are run. If your RCA cables and speaker wire are run alongside your
power cables they will pick up feedback. If this is the case, you will need to run the RCA cable on the other
side separate from your power cable.
2. A poor ground cable connection can cause your amp to clip because improper power is getting to the
amp. Check your ground connection and make sure that the cable is securely tightened.
3. Engine noise – You will know it is engine noise if every time you rev your engine the noise gets louder.
You can install a ground loop isolator on the receiver’s power lead to cut down on signal pollution. Most of-
ten, however, engine noise comes from a loose or intermittent ground connection. Make sure your ground
connection is tight and that you are using the proper gauge cable.
4. If your gain on your amp is set to the max, and your receiver has a high preamp voltage it will cause
some unwanted noise. To properly set your gain, play a CD or other music. Now put the receiver volume
to 75 – 80% of the max. Then slowly turn the gain of the amp to a setting where you do not hear a loud
hiss. A low hiss is acceptable as with music playing you will never hear it. Please note the amp gain is not
a volume control. It is meant to be matched to the preamp voltage of a head unit. It is important to properly
set your gain when you buy a new amp.
CAUSE/SOLUTION