--- In Rob Danielson <>
wrote:
>
> At 11:15 PM -0600 7/4/06, Bruce Wilson wrote:
> >Clay has pointed out that my nifty new all-singing all-dancing
apparent
> >noise is just the self noise (in dB) - 34. The 34 comes from 94
dB SPL per
> >pascal minus the 60 dB I assumed for a small signal. I'll leave
it for now,
> >but it isn't saying anything that the self noise in dB or dBu
didn't already
> >say.
> >
> >I've begun to version the spreadsheet. v1.1 is now available.
> >
> >http://science.uvsc.edu/Wilson/downloads/MicrophoneComparson.xls
>
> Your numbers look about right in terms of ranked performance but
it
> wouldn't it get tricky when the "App. Noise-A dB/1 mPa" numbers
are
> close? For example, it seems unlikely that the self noise
produced
> by two mics with the same net number would produce a close,
audible
> "match."
>
> Is the Rane Note 148 Chart 3 useful in providing a rough estimate
of
> the net noise output taking mic self-noise and sensitivity into
> consideration? http://www.rane.com/note148.html. Rob D.
>
>
Column J in Bruce's spreadsheet seems to calculate the
same values shown in this table, at least based on my
spot check of several mics, incl, Rode NT1A, NTG-2 and
a handful of Sennheiser MKHs.
cheers,
clay
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