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Subject: Re: Microphone.
From: langhaarrocker (phil_at_x-phobie.de)
Date: 2002-10-20


On Sun, 20 Oct 2002 01:19:11 -0500, "Garrett"
<GaryD_at_AdFreeInternet.com> wrote:

>If you want to capture the full frequency range you will need a condensor
>mic, not a dynamic. (A dynamic mic is essentially an electromagnet, with the
>coil mounted on the diaphram. This weighs down the diaphram and kills the
>high frequencies.)

If it was that easy there wouldn't be any dynamic microphones around
any more. Every microphone sounds different and it is a question of
taste, not a question of the frequency range, which mic to choose.
Concerning the upper frequency range: especially with the jukebox
recorder you can almost neglect this as it's analog input doesn't
capture frequencies > 15kHz. That's about the range of a Shure SM58,
the standard vocal mic (dynamic).

>A condensor mic is essentially a capacitor. The diaphram has to be charged
>all the time, so the mic needs a constant direct current, i.e.
>"plug-in-power" or "phantom power".

The mic doesn't draw a constant current. It has to be supplied with a
voltage, though. The voltage source must have quite a high inner
resistance -> striclty speaking it can't be a constant voltage source
as this would disable the condenser mic to alter it.

>Since the JBR has only line in (meaning
>5V, way more than a mic produces), you also need a mic preamp (or else a mic
>with a built-in preamp).

Watch out! 5V exceeds the absolute maximum ratings for the analog
inputs of the MAS! (Datasheet Page 56) The datasheets claim the MAS to
clip at 3.2 V on analog input when operated at 3V.

Phil



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