> I see. Interesting. I probably shouldn't worry about this, but I can't help
> myself! If the input and output impedances are nearly equal, the input
> voltage is being cut in half, correct?
Right.
> And that would mean that the output noise is getting very close to the LS-11
> EIN limit.
Yes, but it is probably still no problem with the low EIN of the LS-11.
> Is it difficult to modify the battery box circuit for the mic capsules to
> lower the output impedance? I am using 6.8k resistors with a 9v battery to
> power two EM172 capsules.
>
> circuit diagram:
>
> http://www.megalithia.com/elect/BATTBOX.pdf
I think the only way to improve the circuit would be to insert a preamplifier
that acts as an impedance converter. Unfortunately, such an additional active
part might in turn also increase the noise floor, if not selected properly. In
other words, one would probably end up with a complete preamp stage with some
gain (let's say 20 dB). But I'm not sure whether that can be really justified.
Regards,
Raimund
|