On 11/19/2010 10:01 AM, Randy Yates wrote:
+22dBu = 0dBFS == +4dBu = -18dBFS.
I'm still not sure if that's FS sine or FS square.
dBFS is a peak level. But since good peak reading meters
(and good average reading meters as well) are pretty rare,
generally we look at the RMS value of a sine wave when
expressing levels.
I determine the maximum input level experimentally by
feeding in a sine wave, watching the digital meter, and
looking at the RMS value of the sine wave when the overload
light just comes on. To be more accurate, I'll record a bit
and examine the level for clipping, boosting the input level
incrementally until I'm sure I'm reaching full scale on peaks.
For outputs, I'll use a program to generate a 0 dBFS sine
wave, play it, and read the RMS level of the output.
--
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it seems that it can be operated without a passing knowledge
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