Charles H. Riggs, III wrote:

Dear fellow audiophiles,

I'm looking for the opposite of a 10db pad for my unidirectional
ECM-66B
lavalier mike. Its output turns out to be quite a bit lower than is ideal
for the Edirol R-1 recorder's mic input, averaging about 10db lower than
is ideal for good SN/R, even with the R-1's input volume set to maximum!


Looking at the spec for this device it seems its microphone input is not
very sensitive (-10dBU), although the spec seems not to distinguish between
the mic and line inputs in this respect. It does make a note about
selecting the right position for the mic type switch which appears to
provide power for suitable electret types. If your mic has a built in
battery then I would recommend setting this switch to the dyn position to
avoid sending power to it.

As it is a very small device I assume a full blown mic pre rather defeats
the object. If you only need another 10dB gain then a transformer as
suggested by others should work OK. Just be aware the input impedance of
the R-1 is quoted at 6K8 so a 3:1 ratio transformer will make this look
like about 750 ohms. This is a little low for a nominal 600 ohm mic but
your ECM-66B is likely to have a much lower output impedance so it should
be OK.

Ian

--
Ian Bell