Phoenix Audio DRS-1R - Mono Class A Microphone Pre-Amplifier/DI in API 500 Series User Manual
Page 5
Additional Setup Information
Firstly, unlike a lot of mic-pre's, the Red LED is not a warning that the
output of the unit is clipping. It is purely there to indicate +16dB output
level.
You can turn the output knob all the way up to maximum and still be sure the
output of the unit will not clip. The amount of headroom on both the input
AND output stage is HUGE!!! There will never be a time when you can't get
a hot enough output, only occasionally too hot an input (then you just simply
turn down the Mic Sens. knob (in Mic mode).
When the DRS-1R is switched into DI mode, the Mic-Sensitivity switch
becomes disconnected and not in use in DI mode.
For Microphone Input:
1: Set the output knob to about the 12 'O' Clock position.
(or just over half-way)
2: Set the mic input level so that the 0dB green LED is just beginning to
come on solidly. (this indicates around 0dB OUTPUT level)
3: If the Red LED is coming on (+16dB OUTPUT level) and you think the
unit is clipping it is NOT the output stage, just step the input gain knob
back one click or two.
4: Turn the output knob up to the level you would like (If you wanted a very
hot output level, ignore the Red LED.
Lets try to explain a little more.............The LED's on the front panel are there
to give you an indication of output level only. This is because most semi-pro
(and indeed, a lot of Professional!) equipment cannot handle the full output
of the DRS-1R, and the LED's give you a good indication of output level so
that you can determine where in the audio chain you may be getting clipping.
They do NOT indicate that the DRS-1R's OUTPUT stage is clipping.