High squeal noise from speakers.
• This is almost always caused by a poorly-grounded RCA
patch cord.
Amplifier(s) gets very hot.
• Check that the minimum speaker impedance for that model
is correct.
• Check for speaker shorts.
• Check that there is good airflow around the amplifier. In
some applications, an external cooling fan may be required.
Distorted sound
• Check that the Level control(s) is set to match the signal
level of the head unit.
• Check that all crossover frequencies are properly set.
• Check for shorts on the speaker leads.
Amplifier will not power up.
• Check for good ground connection.
• Check that remote DC terminal has at least +12v DC.
• Check that there is battery power on the + terminal.
• Check all fuses.
• Check that Protection LED is not lit. If it is lit, shut off amplifier
briefly and then repower it.
High hiss or engine noise (alternator whine) in
speakers.
• Disconnect all RCA inputs to the amplifier(s) – if hiss/noise
disappears, then plug in the component driving the amplifier
and unplug its inputs. If hiss/noise disappears, go on until the
faulty/noisy component is found.
• It is best to set the amplifier's input level as insensitive as
possible. The best subjective S/N ratio is obtainable this way.
Try to drive as high a signal level from the head unit as possible.
Protection LED comes on when the amplifier is
powered up.
• Check for shorts on speaker leads.
• Check that the volume control on the head unit is turned
down low.
• Remove speaker leads, and reset the amplifier. If the
Protection LED still comes on, then the amplifier is faulty.
troubleshooting
Troubleshooting
Speaker Connections
2 CH Mono-Bridged Output
Bridged Mono Output
speakers
LR
MINIMUM
SPEAKER
IMPEDANCE
4 OHMS!
STOP
YES! NO!
2-channel Amplifier
(Operating in Stereo)
4 ohm
4 ohm
Two 4-ohm speakers, wired in stereo,
will present a 4-ohm load to each
channel of the amplifier. Most two-
channel amplifiers will work well in this
configuration.
Two 4-ohm speakers, wired in parallel
to a bridged two-channel amplifier.
will present a 2-ohm mono load to the
amplifier. MOST TWO-CHANNEL
AMPLIFIERS DO NOT SUPPORT 2-OHM
MONO OPERATION! AMPLIFIER DAMAGE
COULD RESULT!
sound around, Inc.
1600 63rd street. brooklyn. ny 11204
4 ohm
4 ohm
2-channel Amplifier
(Operating in
Bridged Mono)
STOP
YES!
NO!
Four 4-ohm speakers, wired in stereo,
will present a 4-ohm load to each
channel of the amplifier. Most four-
channel amplifiers will work well in this
configuration.
Four 4-ohm speakers, wired in parallel
to a bridged four-channel amplifier,
will present a 4-ohm mono load to the
amplifier. MOST FOUR-CHANNEL
AMPLIFIERS DO NOT SUPPORT 2-OHM
MONO OPERATION! AMPLIFIER DAMAGE
COULD RESULT!
s
ound around, Inc.
1600 63rd street. brooklyn. ny 11204
4-channel Amplifier
(Operating in
Bridged Mono)
4 ohm
4 ohm
4 ohm
4 ohm
4-channel Amplifier
(Operating in Stereo)
4 ohm
4 ohm
4 ohm
4 ohm
2CH AMPS
LA
438
LA
538
LA
738
LA
938
LA
1438
LA
1838
LA
2038
11
4CH AMPS
LA
63
LA
83
LA
1038
4CH AMPS
LA
638
LA
838
LA
1038
2 CH Stereo plus
Mono-Bridged
Subwoofer Output
speakers
L
Mono
Subwoofer
MINIMUM
SPEAKER
IMPEDANCE
4 OHMS!
R
speaker
MINIMUM
SPEAKER
IMPEDANCE
4 OHMS!
