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Subject: RE: Re[2]: Microphone.
From: Matthew P. OReilly (
Date: 2002-10-19

Hello M.,
Hey, U!!

(Sorry, I couldn't resist.) <grin>

I had the same problem: I wanted to connect an electret condenser mic
capsule / such a mic to the AJB. I think the only way is to connect a
mic amplifier to the AJB.

I soldered one with an operational amplifier in it - that means it needs
power, which I took from a 9V battery. The mic capsules also needs power
(>1,5V, ~2mA).

JimG and I had a good off-list discussion about this... he sent me some good
links, which I pass on to you:
(This describes part of the problem, but doesn't give really us an
applicable solution.)
(This one actually gives three solutions. The middle one is the one we're
interested in. There's a really good link
to a white paper about transformers, too.)
These are actual products which should do what we want. The Shure cable is
about $50 *less* than the other one.

I just ordered one of the Shure cables from:

Big thanks to JimG for finding all this.

A dynamic mic has a greated output power, so it works with a smaller
amplification (or maybe without an amplifier?). There exist simple
amplifiers with transistors. So I think that's why the Archos mic is a
dynamic mic.
I'll try both when I receive them and let you know what the verdict is.
Hopefully this cable will be sufficient for either type of mic.

Bye, Uwe.
Heh, see "U".

(Last one, I promise. :-)

Page was last modified "Jan 10 2012" The Rockbox Crew