Record Levels - what is +4dB / -10dB

[Bob Zimmer]

At 10:51 PM 4/19/96 -0500, you wrote:
>...  Also, be aware that digital recorders don't have "headroom" above 0dB,
>which means a louder signal will cause non-musical distortion.  Since
recording >engineers are used to tape, where an extra-hot signal will
sort-of saturate the >tape ( not really causing distortion ) the
manufacturers of ADATs and other >digital recorders adjust the scale to give
more apparent headroom.
>

0 Vu actually represents the highest value that can be stored digitally.  If
the signal exceeds that level, it is clipped.  What happens is that the top
of the waveform (the portion that exceeds that highest level) is cut off in
a straight line.  This makes a most unpleasant sound!

As mentioned, to allow some notion of headroom, some manufacturers will
purposely set 0 Vu to be a couple of dB below the actual clip point to allow
for unexpected peak levels.

Bob
 

  >=== Bob Zimmer -- Philadelphia PA ===<
  >=== bzimmer at voicenet.com          ===<