I guess I do not understand the impedance issue as well as I thought I did.=
I thought the main problem was when the impedance of the microphone and th=
e impedance of the input on the recorder were nearly equal, in which case t=
he voltage gets divided, cutting the input voltage in half. I have observed=
this in action using the EM172 capsules (2.4k ohms) with my LS-11 (2k ohms=
). The EM172s work better with the PCM-M10, with its 20k ohm input impedanc=
e. =0D
=0D
It has been my understanding that the ideal situation is for the recorder i=
nput impedance to be about 10 times higher than the microphone impedance. I=
believe that has been stated on this list quite a few times, but maybe I d=
idn't understand.=0D
=0D
John=0D
=0D
=0D
---In <> wrote :=0D
=0D
=0D
John, =0D
=0D
Think of it another way. A 200 ohm mic feeding into a 20K input is a 100 =
=0D
times impedance mismatch. If you fed the mic through a 1:10 transformer to=
=0D
get an impedance match, you would get a 20 dB rise in level (OK less 6dB).=
=0D
Life is not quite that easy, and the "noise optimum" match may be differen=
t, =0D
but that has a long explanation. :-) =0D
=0D
=0D
=0D
=0D
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