Genz-Benz 300 ユーザーズマニュアル

 –  The Shenandoah

®

 Compak 300  is equipped with 2 types of input jacks. The ¼” input is unbalanced and 

“line level” with a usable sensitivity from 100 mV to 1.6 volt. The input impedance is 270 k ohms. The ¼” input will also 

accept most active balanced line sources, automatically unbalancing them by recognizing the tip portion of the 

balanced signal.  If an instrument offers an unbalanced output it should be connected to the unbalanced input of the 

Shenandoah

®

 amp.  Additionally, the precision input scaling preamp contains a 45 Hz, 12dB/octave high pass filter 

(more effective and less intrusive than the more common 6 dB filters) and an “RFI” filter (radio frequency interference) 

to eliminate unwanted noise. The XLR input jack is balanced and “microphone level”, with a usable sensitivity from 

-60dBv to -30 dBv.  It is not a line level input. It contains a precision full range differential microphone preamp with 

phantom power. For use with higher-level sources (such as the balanced line level output from a keyboard or other 

instruments), a balanced pad network will be necessary to use the balanced input. For instance, a Rapco, “Pad Blox”, 

-20 or -30 pad or similar product could be used.

 – A unique feature of the Shenandoah

®

 Compak 300 is the ability to mix the 

XLR balanced and ¼” unbalanced inputs. In many situations, this effectively makes the amplifier function as a 3 chan-

nel amplifier. The most effective way to use this feature is to set the volume on the channel using the XLR microphone 

input and then adjust the level control on the instrument itself (assuming that it has one) to blend levels between the 2 
inputs. Equalization will be common to both inputs on the channel.

 –This red O/L LED senses the input signal to the preamp section and warns of input overload.  

For the cleanest signal possible, this LED should only flash with the strongest signal peaks. Adjust this sensitivity with 

the volume control of your instrument and the Shenandoah

®

 Compak 300’s channel volume. Adjust the final overall 

volume with the amps master volume.

 –  Each channel is provided with a phase reverse switch. By reversing the phase of the input  

signal, feedback tendencies can be reduced if caused by sympathetic vibrations between the speaker and the 

instrument. Under some conditions, changing the phase can drastically improve the acoustic output from the amplifier 

and can improve the playability of some instruments.

 – The Shenandoah

®

 Compak 300 contains a studio 

quality 24-bit, 15 program digital effects processor. Using pro audio industry digital processing hardware, we have 

achieved realistic, high quality effects algorithms. Level differences are normal when switching between different ef-

fects; just adjust the channel send and master level controls accordingly. The effects level control on each channel 

adjusts the send level to the digital effects processor. The digital effects level in the master section controls the effects 

return level from the processor.  In general, turning up the channel effects send will yield more lush effects. 

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