lilyplants wrote:
> Dan,
> are you saying that gina had an external mic preamp between her mics
> and both mic
> inputs to use all the amplification from the external mic preamp or
> add to the FR2-LE pre
> amp?
To add to it. My exclamations referred to the incorrect connection of
the preamp's line output to the recorder's mic inputs. That connection
almost guarantees either a noise or an overload problem. The Fostex
has line inputs, but apparently XLR to TRS cables weren't available to
connect up the preamp properly. But I don't think she needed a preamp
at all.
> Secondly, are you saying you used your external mic preamp for one
> channel and the FR2-
> LE mic pre amp for the 2nd channel?
Yes.
> And that the results were that you got an equal gain
> from both mics with that configuration?
Equal gain when the channel with the preamp on it had its gain trimmer
(the tiny knobs) all the way down, and the channel with the mic
directly into it had its gain trimmer all the way up.
The important part of the experiment was listening to see whether
there was significantly more noise on one side or the other. Didn't
seem like it, but as I said we didn't really finish the job by
listening in a quiet place.
> If that's true, I don't see why you have to turn the gain (volume?)
Same thing; engineering vs consumer vocabulary. Volume controls are
gain controls. But "gain trimmers" are usually in the feedback loop of
the preamp and don't go silent at the minimum position. Also gain
trimmers usually have a big jump in gain at the maximum position. So
they are designed to be set rather than moved a lot.
> all the way up to get
> enough levels to read.
What level you see on the meter will depend on the sensitivity of the
mic, and how loud the sound is. The Fostex doesn't have a lot of extra
gain, but it has enough for quiet soundscapes with reasonably
sensitive mics.
The FR-2LE has two gain trimmers and a master record level control.
You could also call it a master fader.
Running the trimmers all the way up isn't a problem. Inexperienced
people hear the big jump in gain when they approach the maximum and
think "whoa, that's too noisy." But when you turn the gain up, you
turn the headphones down and all is well.
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 = 0dBFS, +/- 5dB. That setting will
work for 99% of soundscapes.
> Sorry, I'm new at this (had to look up MP-2).
We're here to help.
-Dan Dugan
|