> I wouldn't think that impedance matching would be an issue with the
> PCM-M10. It has a very high impedance input (I think it's 20k ohms), so
> very little loss from voltage division.
John,
Think of it another way. A 200 ohm mic feeding into a 20K input is a 100
times impedance mismatch. If you fed the mic through a 1:10 transformer to=
get an impedance match, you would get a 20 dB rise in level (OK less 6dB).=
Life is not quite that easy, and the "noise optimum" match may be different=
,
but that has a long explanation. :-)
> I was thinking as I drove to work this morning that it makes sense that
> the overall signal would be higher using the built-ins on the PCM-M10
> because they are grabbing sound from all directions - they are
> omnidirectional microphones.
> Whereas the shotgun microphone (I wish we had
> a less violent word)
the director tube microphone
> is rejecting sound from the sides.
(trimmed neat description)
< '''
> But if the only sound source is, say, a single bird, and the "shotgun" is
> pointing right at it, then I would think the "shotgun" microphone would
> result in a higher level than the omnis, even if it is a little less
> sensitive.
>
> Does that make sense?
Yes, but it depends how you measure sensitivity. In a spec, it is with a
point source of sound. In the wild or in a reverberant space, we immediatel=
y
hear the benefit of a gunmic (UK term) but you won't see this in any tech
spec.
David Brinicombe
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