That Gain Knob

[salty james]

Question, folks. Around The gain knob are the levels for line and mic. I'm pretty certain that line level is the outside numbers and mic the inside numbers, and that unity for line level is at roughly 10:00. But where is unity for mic level? is it that zero at 7:00 / full counter clock wise?
Great forum. Thank you all!
Salty

 

[Phil Tipping]

My understanding is that there is no unity mark for mic signals as they will always need amplification. Line-level signals are higher in level, so are closer to the inner working levels of the machine. This means they may need amplifying or they may need attenuating, so the pre-amp is designed to do both. The unity mark is where no gain or attenuation is required, which gives the best signal to noise ratio.

 

[Max Relic]

I'd say that musical instruments and devices usually present standard +4 / -10 dB input/output level, which simplifies the design of an input stage. Microphones present a more wide range of sensitivity and output level hence I see trying to define a "unity gain" point is more challenging in design terms. IMO

 

[shredd]

I'm no expert (Resident Maroon here)...but I'd be willing to cast my vote that the "unity" marking on the solid white ring marking the range (-10 > +40) of the control is for the LINE input. The INNER ring, for MIC input, is graduated, ranging from 0 > +50. Two SEPARATE scales (as you observed in OP), to use depending on what sound-source is in use at the time. That "unity" marking would apparently apply only to the LINE scale.

I guess I'd risk implying you're as stewpyd as I am if I reminded you to observe proper gain-staging practices...at the very least, use the "clip" light and PFL-metering function...