Mackie SRM450V2 ユーザーズマニュアル

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5
The Cabinet
The SRM450v2 cabinet was designed to be the strongest 
molded composite cabinet on the planet. This material is as 
strong as concrete, and rigid enough to prevent unwanted 
vibrations in the cabinet. It has built-in fly points for    
hanging, and a socket in the bottom for mounting on a  
tripod stand. Although it is an exceptional choice for    
installed sound situations, its light weight and durable  
finish also make it ideal for portable sound system use. The 
asymmetrical trapezoidal design of the cabinet makes it 
easy to use as a floor wedge for stage monitor applications.
The Active Advantage
There are a number of advantages to using an active 
speaker system over a passive loudspeaker:   
 
•  The internal crossover is active, and its low power  
circuitry operates on line-level signals. It does not 
waste speaker-level power like a passive crossover  
with large coils, caps, and resistors.
•  The input signals are crossed over before they reach
the amplifiers, so each amplifier only receives the   
correct frequency range for its driver.
•  The amplifiers are designed specifically for these
speaker load impedances. There is no guesswork as 
to what load each amplifier has to drive, so they can 
provide maximum acoustic output from the speakers, 
yet minimize the danger of speaker damage due to 
overdriving a lesser amplifier.
•  The connecting wires between the amplifier outputs
and the drivers are kept to a minimum, so the damping 
factor of the amplifier isn’t compromised by the  
resistance of long speaker cables. In addition, all the 
power from the amplifier is transferred directly to the 
drivers with no speaker cable losses.
•  The acoustic sum of the outputs from the two drivers
is optimized electronically, as well as physically, so the 
amplitude response is flat and there is no lobing error.
•  The presence of active circuits within the speaker
cabinet allow the designer to add on extra details, such 
as a high quality mic/line input section.
In short, all the complex interconnected components 
in the system are designed to work in harmony with each 
other to produce the best possible sound. (Even for Uncle 
Bert’s star performance on spoons!)