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David Nebenzahl David Nebenzahl is offline
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On 11/19/2010 7:45 AM Scott Dorsey spake thus:

In article , Randy Yates
wrote:

No. There's an informal standard used in the film industry and in
many broadcast applications of +4dBu = -20dBFS, but it's never
been codified as an official standard. The informal standard,
though, is (I believe) based on an rms scale -- in other words, a
tone that would read 0 VU on a VU meter calibrated to +4dBu would
be -20dBFS. Correct me if I'm wrong on that last bit, but that's
what I think is the case.


There seems to be no universal agreement, but you are close to what
this guy says (under "Here come the numbers..."):

+22dBu = 0dBFS == +4dBu = -18dBFS.

I'm still not sure if that's FS sine or FS square.


That's assuming a sine wave.

Unfortunately if you use that standard and you record a trumpet with peaks
at 0 dBu, you'll clip the hell out of your converters.

This is because trumpets aren't making sine waves.


Nor violins. (Make pretty close to a triangular wave, I believe.)


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