Mackie SRM450V2 Benutzerhandbuch

12

HEATSINK

THERMAL

PEAK

LOW CUT

The amplifiers inside the SRM450v2s are 
convection cooled by a large heatsink. 
For efficient cooling, it is important to 
allow at least six inches of free space 
behind the SRM450v2.

If you use the SRM450v2 on its side for 
stage monitor applications, we highly 
recommended that you engage the rear 
panel LOW CUT switch. This will allow 
more power for useful monitor    
frequencies, while reducing the    
possibility of overheating.

If the ambient temperature in the room is high, though 

highly unlikely, it could cause the amplifiers to overheat. 
In this case, you should try aiming a fan at the heatsink to 
increase the air flow through the fins.

During a performance, don’t have it cranked so high that 

the rear panel PEAK LED is blinking frequently or lighting 
continuously. You should turn down the LEVEL control a 
notch or two to avoid overheating the amplifiers or your 
neighbors.

If the amplifiers do overheat, a built-in thermal  

switch will activate, placing the amplifiers into standby. 
When the amplifiers have cooled down to a safe  

 

operating temperature, the thermal switch will reset    
and the SRM450v2 will resume normal operation.

Be sure the SRM450v2 is plugged into an outlet that is 

able to supply the correct voltage specified for your model. 
If the voltage should drop below 97% of the specified line 
voltage, the built-in amplifiers will no longer be able to 
supply rated power. (They will continue to operate down 
to 75% of the rated line voltage, but won’t reach full power, 
resulting in lower headroom).

Under maximum SPL conditions, where musical peaks 

are clipping, the SRM450v2 120V model draws 2.5 amps on 
average (1.3 amps for the 240V model). Under normal  
conditions, the current draw is below 1 amp.

We recommend that a stiff (robust) supply of AC power 

be used because the amplifiers place high current demands 
on the AC line. The more power that is available on the line, 
the louder the speakers will play and the more peak output 
power will be available for cleaner, punchier bass. A    
suspected problem of “poor bass performance” is often 
caused by a weak AC supply to the amplifiers.

A 240 VAC center-tapped service entrance transformer 

serves the majority of AC outlets encountered in homes  
and clubs (in the U.S.). This provides two phases of AC 
power on either side of the center tap, at 120V each.

If lighting is used in a show, it is preferable to power 

the lights from one leg of the service, and power the audio 
equipment from the other leg. This will help minimize  
noise from the lights coupling into the audio (particularly  
if SCRs, or light-dimmer switches, are used).

Wherever possible, connect all of your equipment to the 

same electrical circuit. This will help reduce the possibility 
of a ground loop problem causing an annoying hum in your 
speakers. 

Low power components such as tape decks, mixers,  

effects processors and CD players should be connected to 
the same outlet as the SRM450v2s. Use fused power strips 
as shown in the diagram on the next page. Make sure that 
the total current draw of your components does not exceed 
the capability of the outlets and power strips.