> The S-to-N Ratio on the Sony threw me off. I thought the higher the numbe=
r on that, the better. The "18db" spec seemed low indeed.
>
>>> FR: 40Hz ~ 20kHz
>>> Dynamic Range (Typical) 80dB or more
>>> Signal-to-Noise Ratio 18dB SPL (Average) ???????????????
>>> Maximum Input Sound Level 100dB SPL or More
The S/N figure is obviously a mistake. I'm going to assume that they mean "=
self noise" with that 18 dBSPL figure. I also suspect that an ignorant edit=
or changed "A" to "Average." If you subtract the 80 dB Dynamic Range from t=
he 100 dBSPL Maximum Input Level, you get 20 dB, which is close to the 18, =
and if the Dynamic Range figure is broad-band and the self noise is A-weigh=
ted, it all makes sense.
Yes, with real Signal-to-Noise Ratio figures larger is better. The "signal"=
in the case of microphones is 94 dBSPL, so you can figure the self-noise b=
y subtracting the S/N from 94.
18 dBA self noise is fine for most applications, it could deserve to be cal=
led "low noise," but it isn't quiet enough for distant sources or quiet amb=
iences. Our colleague here Rob Danielson has established a specification of=
16 dBA self-noise as the maximum acceptable for soundscape recording.
Using that standard a mic suitable for nature ambiences should have an S/N =
of at least 94 - 16 =3D 78.
-Dan
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