DAN:
>> Getting started: set the master at 2:00. Hold your left mic at arm's
>> length and talk to it in a normal conversational voice while
>> adjusting
>> that channel's gain trimmer so that the meter reads about -5dB. Put
>> your two mics together and adjust the other channel so the sound in
>> the headphones is right in the middle of your head. Cut three little
>> tape triangles to mark the positions of the knobs. Voila, you're
>> balanced and calibrated to 70dBSPL =3D 0dBFS, +/- 5dB. That setting
>> will
>> work for 99% of soundscapes.
>>
HECTOR:
> Thank you for sharing this information. Have you done this calibration
> with the AT-3032?
Roughly, with Gina's system at the workshop.
> If yes then what was the trimmers' final position?
I used all the way up.
> I
> just tried this with my FR2-LE and AT3032s and the trimmers ended
> almost all the way up.
Sounds good to me.
> Actually it was a little difficult for me to do
> it because it seems I'm getting the -5db right at the point where the
> trimmers start the big jump and this is a quite difficult spot to fine
> tune, specially when trying to make both mics equal.
Yes, that's why you want to use the master level control for most
adjustments after you're done fiddling.
If something is so loud that the master is below 10:00, better lower
the trimmers. I'm just guessing, careful experimentation with the
overload level would determine the precise point.
You're right, being in the touchy range of the trimmers makes
calibrating to a mark difficult or useless.
I'm dreaming of a cheap acoustic calibrator for nature recording--like
a tiny bullhorn with a radio antenna that pulls out to set a standard
distance from the mic.
-Dan Dugan
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