Bruce Wilson wrote:
> To be fair, those could be the correct numbers if the overall gain
is very
> low (for example, if the noise figure was calculated at 13 dB gain
rather
> than 53 dB gain) and the 0 dBFS level is very high (like 1000 v or
something
> absurdly high). Since the unit is primarily intended for concert
recording
> it might likely be used at low-gain settings, though it is still very
> unlikely anyone will get 1000+ volts out of any known mike, even at
an AC/DC
> concert.
Yes, according to their specification, the -140dbFS figure applies to
the minimum gain setting. However, there is currently no A/D converter
chip available that could provide a dynamic range of 140 dB.
Nevertheless, the specified FFT-based 140 dBFS is not completely wrong
(if would be accurate if the FFT size was declared). In this way, one
could create any desired large number just by increasing the FFT size
(and decreasing the frequency bin width).
Regards,
Raimund
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