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Subject: Re: Microphone.
From: Garrett (GaryD_at_AdFreeInternet.com)
Date: 2002-10-20


Sound Professionals has a collection of small mic preamps, some designed
with the JBR in mind:
http://www.soundprofessionals.com/cgi-bin/gold/category.cgi?category=540

Also check out the mics, incl. mic/pre combos and stealth mics.

---Here is a short microphone tutorial for JBR users---

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.)

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". 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). Some preamps (including the SP-PREAMP-2 and
SP-PREAMP-3 at Sound Professionals) will supply the needed plug-in-power to
the mic. (If the preamp does not supply plug-in-power, you must get a
separate battery power supply, or a mic with one built in.)

At the same price level, omnidirectional mics generally provide a wider
frequency range than cardiod (unidirectional). However, cardiods target the
sound better and reject ambient noise and room echo.

A "stereo mic" of course is two mics mounted together; a good choice for mp3
recorders.

For further reading: Stereo Microphone Techniques by Bruce Bartlett.
Or the web page: "Stereo Mic Techniques for Field Use":
http://home.sprintmail.com/~markgriswold/articles/articles/stereo/stereo.htm

---Garrett---



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