Soundstream 644s 用户指南

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The REFERENCE644s amplifier employs an extremely efficient  Auto High 
Current™ power supply (patent pending).  This new power supply circuitry 
automatically customizes your amplifier for optimum efficiency and power 
output into virtually any impedance load.  When other brand amplifiers are 
driven at low impedances (i.e., 1 ohm or less), they shut down, squash 
dynamics and power output (called current limiting), or waste huge amounts of 
power (i.e., low efficiency).  All of which reduce the "real world" power the 
amplifier can produce in the car.  Soundstream's Auto High Current™ power 
supply allows the REFERENCE amplifiers to be one of two types of amps:  
either producing maximum power at higher impedances (perfect for satellites) 
or at lower impedances (usually with multiple subwoofers).  This is done by 
letting the amplifier's power supply continuously monitor the impedance of the 
load the amplifier is driving.  If the impedance drops too low, the power supply 
will automatically switch into High Current mode.  It will stay in this mode until 
the amplifier is turned off.  The next time it is powered up, it will be in the High 
Power mode.   
 
Unlike other amplifiers, Soundstream’s REFERENCE644s amplifier can be 
configured to drive virtually any impedance and make maximum power!  The 
major advantages of this power supply are: 

 

•

awesome dynamic power capabilities 

•

added continuous power with higher voltages 

•

increased amplifier efficiency and reliability 

 
Because of the dynamic properties of most music, all audio components 
should be able to react accordingly.  Thanks to their unique power supplies, 
the REFERENCE amplifiers can comfortably exceed their rated power for 
dynamic portions of the music. 

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