Bruce,
Thanks, you are welcome. I'm also doing that for my own reference in
order to better understand the performance of the various recorders.
> For table at the link below, I'm trying to figure out what the
"Input Level"
> column is. Is that the maximum signal level that gives no (or very low)
> distortion when the recording level is set at maximum?
Exactly, it is the maximum signal level that can be processed by the
A/D converter without clipping (and which corresponds to 0 dBFS).
> If so, maybe reporting dBu AND mV might be easier when comparing
> mics (or at least define what dBu's are and which way is bigger.
0 dBu corresponds to 0.775 Vrms. For instance, -40 dBu would be
equivalent to 7.75 mV. I just added the mV numbers to the table.
> And how are you handling those
> recorders that have level limiters when the signal gets big? That
would add
> distortion, so maybe a measurement of the max signal level at, say, 0.1%
> distortion, might make the comparison more uniform.
That's a good question. I generally disabled the limiter options on
all recorders. Otherwise, it would be difficult to provide uniform
numbers. Actually, I do not measure the input levels directly.
Instead, I record a 1 kHz reference signal that provides a level well
below 0 dBFS. I then calculate the input level that would correspond
to 0 dBFS.
Regards,
Raimund
> But overall I think you have done the community a very great service by
> making these measurements available. Thanks!
>
> Bruce Wilson
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