User's Manual

10
Troubleshooting
This section suggests several possible solutions to some com-
mon problems encountered by USW-1P users and is not
intended to be a thorough troubleshooting guide. Contact
Meyer Sound for additional information and documentation.
The On/Temp. LED does not illuminate, there
is no audio, and the power supply fan is
off.
1. Make sure the AC power cable is the correct type for the
regional voltage and that it is securely connected to the
AC inlet then unplug and reconnect the AC cable.
2. Use an AC voltmeter to verify that the AC voltage is
within the ranges 88–264V, 47–63 Hz.
3. Call Meyer Sound Technical Support.
The On/Temp. LED is illuminated but there is
no sound.
1. Verify that the audio source (mixer, EQ, delay) is send-
ing a valid signal.
2. Make sure the XLR cable is securely fastened to the
XLR audio input connector.
3. Verify that the XLR cable is functioning by substituting
another cable or by using the cable in question in a
working system.
4. Send the audio signal to another speaker to insure signal
presence and that the level is within the proper range.
Turn the source level down before reconnecting the
audio input and increase the level slowly to avoid a
sudden blast of sound.
5. If possible, monitor the audio source with headphones.
Hum or noise is produced by the speaker.
1. Disconnect the audio input. If the noise persists, the
problem is within the USW-1P. In this case return the
unit to the factory or nearest authorized service center. If
the hum ceases, the noise originates somewhere earlier
in the signal path.
2. Make sure the XLR cable is securely fastened to the
XLR audio input connector.
3. Send the audio signal to another speaker to insure signal
presence and that the level is within the proper range.
Turn the source level down before reconnecting the
audio input and increase the level slowly to avoid a
sudden blast of sound.
5. Hum or noise can be produced by a ground loop. Since
the USW-1P is effectively ground-lifted, the loop must
be broken elsewhere in the system.
The audio produced by the speaker is dis-
torted or compressed but the limit light is
not illuminated.
1. Make sure the XLR cable is securely fastened to the
XLR audio input connector.
2. Send the audio signal to another speaker to insure that
the level is within the proper range. Turn the source level
down before reconnecting the audio input and increase
the level slowly to avoid a sudden blast of sound.
3. Monitor the audio source with headphones.
The audio produced by the speaker is highly
compressed and the limit light is constantly
red.
1. Turn down the level of the input signal to the speaker
system.
There is sound but it is does not seem to
be at full power and the On/Temp. LED is
yellow.
This occurs in conditions where the heatsink temperature
reaches 85°C (185°F), indicating that the amplifier is ther-
mally overloaded. The limiter threshold has dropped to a safe
level, so the audio level is reduced.
1. Make sure there is enough clearance above, below, and
behind the unit.
2. Make sure there is sufficient air flow around the unit.
3. Avoid exposing the heatsink to direct sunlight if the
ambient temperature is high.
4. If the ambient temperature is greater than 30° C and this
condition occurs frequently, contact Meyer Sound to
order the optional Fan Kit.
See the section Amplification, Limiting, and Cooling
System on page 6 for a complete discussion about the
cooling system.
There is no sound, the On/Temp. LED is
dim or off, and the power supply fan is on
high speed.
This extremely rare event occurs when the power supply over-
heats, causing a 1-2 minute interruption in operation. The unit
turns on again when the power supply has cooled sufficiently.
1. Make sure there is at least six inches clearance behind
the unit.
2. Make sure there is sufficient air flow around the unit.
See the section Amplification, Limiting, and Cooling
System on page 6 for a more information about the power
supply’s internal fan and cooling system.