CHAPTER 3

M’elodie is performing within its acoustical specifications and operating at a normal temperature if the limit LEDs are lit for no longer than two seconds, and then go off for at least one second. If an LED remains on for longer than three seconds, that channel enters hard limiting, with the following negative consequences:

■Increasing input level will not increase volume.

■Distortion increases due to clipping and nonlinear driver operation.

■The lifespan of the driver is reduced because it is sub- jected to excessive heat and/or excursion, and eventual damage over time may occur.

NOTE: The limiting circuitry utilizes optical limiters that add no noise and have no effect

on the signal when the limiter is not engaged and the LED is inactive.

COOLING SYSTEM

The M’elodie amplifier modules rely solely on natural convection for cooling. The heatsinks used in the amplifier modules allow natural convection cooling from air flowing over the heatsink. The efficient design of the amplifier and heatsink profile helps keep the temperature on the amplifier low even when the loudspeakers are being used at high ambient temperature, in tightly packed conditions, and/or at high continuous levels.

If the temperature of the heatsink reaches 75° C (167° F), the On/Temp. LED on the rear panel turns from green (On) to red (Temp.). The unit continues to operate normally even if the On/Temp LED is red, but this is an indication that the unit is reaching its maximum dissipation. A reduction of the SPL is recommended at this point.

NOTE: In the highly unlikely event that the heatsink temperature reaches 95˚ C (203° F),

the M’elodie loudspeaker automatically shuts down until AC power is removed to allow the heatsink to cool down. If the M’elodie loudspeaker shuts down again after cooling and reapplying AC power, contact Meyer Sound for repair information.

CAUTION: The heatsink can reach temperatures of up to 95° C (203° F) during

extreme, high-level operation for extented periods of time. Use caution when approaching the rear of the cabinet.

CAUTION: To keep the heatsink from getting too hot, ensure proper ventilation around the

loudspeaker.

When the heatsink temperature decreases to 65° C (145° F), the On/Temp LED changes from red to green.

CAUTION: If loudspeakers in a system begin to shut down due to excessive heatsink

temperatures before reaching the required SPL, consider adding more loudspeakers to satisfy the SPL requirements.

TIP: The RMS remote monitoring system can be used monitor the temperature of the

heatsinks.

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