Meyer Sound UP-4XP ユーザーズマニュアル

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When wiring UP-4XP loudspeaker 

cables, it is extremely important that each pin 

be wired correctly. Make sure the 48 V DC from the 
external power supply is wired directly (and only) to 
the 48 V DC pins on the UP-4XP loudspeaker con-
nector, and that the polarity is observed (negative to 
negative, positive to positive) to avoid damage to the 
loudspeaker. In addition, make sure that audio pins 
are wired correctly; polarity reversals for audio signals 
affect system performance.

The UP-4XP has a three-color LED on its rear panel that 
changes color to indicate the loudspeaker’s status.

When powering up the UP-4XP loudspeaker, the following 
startup events occur and are indicated by the LED:

1. The LED flashes multiple colors during power-up 

sequence.

2. After a pause, the LED turns solid green, indicating the 

power-up sequence has completed and the loudspeaker 
is ready to reproduce audio.

If after the power-up sequence the 

LED does not turn solid green (instead flashes 

multiple colors or stays solid red) and the UP-4XP 
does not output audio, the loudspeaker has encoun-
tered an error and may need to be serviced. Contact 
Meyer Sound Technical Support.

If after the power-up sequence (or 

during operating) the LED turns solid red and 

the loudspeaker continues to output audio, the loud-
speaker’s voltage may have dropped below 25 V DC. 
When encountering these conditions, operation of 
the loudspeaker should cease and its power supply 
and cabling should be verified.

The UP-4XP LED turns yellow to indicate limiting. When the 
LED is solid yellow, limiting is engaged for the high-fre-
quency channel. When the LED flashes yellow (on and off), 
limiting is engaged for the low-frequency channels. When 
limiting is engaged for a channel, its gain is reduced. When 
engaged, the limiter protects the loudspeaker’s drivers and 
prevents signal peaks from causing excessive distortion in 
the loudspeaker’s amplifier, thereby preserving headroom 
and maintaining smooth frequency responses at high levels. 
When source levels return to normal, below the limiter’s 
threshold, the LED turns green and limiting ceases.

The UP-4XP performs within its acoustical specifications at 
normal temperatures when the UP-4XP LED is green, or 
when limiting is not continuous. If limiting activity is continu-
ous, the loudspeaker is nearing the limits of its operating 
capabilities where:

■

Increases to the input level have no effect.

■

Distortion increases due to clipping and nonlinear driver 
operation.

■

The drivers are subjected to excessive heat and excur-
sion, which will compromise their life span and may 
eventually lead to damage over time.

The UP-4XP LED turns yellow when 

the loudspeaker’s signal rises 2 dB above the 

limiting threshold, and indicates a safe, optimum level 
has been exceeded. If the UP-4XP loudspeakers in a 
system begin to limit before reaching the desired 
SPL, consider adding more loudspeakers to the sys-
tem to achieve the desired SPL without exposing the 
loudspeakers to excessive levels and possible over-
heating.

The UP-4XP LED turns solid yellow when its heat sink tem-
perature reaches 65° C (145° F), indicating the unit is reach-
ing its maximum heat dissipation and a reduction in SPL is 
recommended. While the UP-4XP will continue to operate 
while the LED is yellow, the limiter threshold is lowered to a 
safe level (causing the output level to be lowered by 3 dB) to 
prevent the loudspeaker from overheating. When the tem-
perature of the heat sink cools to 50°C (122°F), the LED 
changes from yellow to green and the limiter threshold 
returns to normal.