SAFETY PRECAUTIONS:
Always provide adequate ventilation by allowing the top vents of your 500 series power supply chassis to
remain unobscured. Due to the vacuum tube and the internal secondary power supply, the 583s will get
warm, blocking or defeating any existing vent is not recommended.
Never position the power supply directly above other heat generating sources such as a power amplifier.
Always provide a source to ground (earth.) Never under any conditions should a power cord that has the
3
rd
prong for ground missing or defeated be used with the power supply.
Do not place the 583s in an area where there is a potential for fluids to fall, spill into or come in contact
with the 583s. If you notice fluids or moisture present inside the 583s
DO NOT
turn power on! Contact
LaChapell Audio for direction.
The 583s should only be used with power supply frames that have a >120ma rating per bay.
Controls:
INPUT GAIN:
Adjusts gain within the input
stage of the preamplifier and has a typical range of
>30db via a fully variable 100kohm potentiometer.
OUTPUT GAIN:
Throttles gain to the output
stage of the preamplifier and has a typical range of
40db via a fully variable 100kohm potentiometer
.
48V:
Supplies 48v of DC current to pins 2 & 3 of
the input jack for condenser microphones.
-20dB:
Places a 20dB pad in front of the micro-
phone input transformer. This feature is defeated
when using the Hi-Z stage.
POLARITY:
Reverses the polarity of pins 2 & 3
on the output jack.
INPUT:
Allows the user to alternate between
microphone input and Hi-Z input.
All Toggle switches will illuminate red when their
associated function is active
.
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