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Scott Dorsey Scott Dorsey is offline
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Default Attenuate or run hot mic directly into A/D convertor?

wrote:
We've got some nice pres here (Millenia, Symetrix, Great River, Manley)
but consistently run into problems of too much gain when tracking kit.
E.g. with the Millenia on its lowest settings a 451 on the bottom of
the snare clips our A/D convertor.


On the lowest setting, the HV-3 has about 18 dB of gain. I think the Great
River can be cranked down almost to unity.

I'm considering two options, neither of which I know much about and
would appreciate any advice as to the merits of either:

1. Using an inline pad on the mic cable - Shure A15AS or Audio Technica
8202. Do these degrade the signal? Do they pass phantom power ok?


They don't degrade the signal and they pass phantom power fine. Every
studio should have a drawer full of these. They are absolute and total
lifesavers for field recording work.

2. Skipping the preamps altogether and running the mics directly into
the A/D convertor. Would this work? My concerns are (i) would it be
loud enough? (ii) impedance issues? (iii) How to handle phantom power?
If we buy an inline phantom power box is this going to blow up the A/D
convertor? And does the quality of the phantom power unit affect the
sound quality? (e.g. Behringer do cheap little ones).


The phantom power unit has at least blocking capacitors and maybe a
transformer (unless it's the AKG unit, which allows phantom to appear
on the _output_ as well as the input). The quality of those capacitors
or transformer is still important.

The impedance is still an issue, but if you're going into an old-style
600 ohm input, most mikes will be happy. I used to run the RE-20 as a
kickdrum mike directly into the inputs of the Ampex with no problem.
There's no reason you can't do that also.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."