Eventide BD500, Руководство оператора

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Page 20 Appendix A Optional AES/EBU Digital Audio BD500 Broadcast Profanity Delay
©Eventide Inc. 1995-1999
doc release 10
has been present since power-up. The AES/EBU outputs will be active and the rate will be the same as the
input analog sample rate. If the fallback variable is set to
UNL
(unlock) the unit will mute the outputs.
Notes and Warnings for AES/EBU Operation
The input attenuation (
INP
) configuration parameter does not change the audio levels for AES/EBU inputs.
The output attenuation (
OUT
) configuration parameter does affect AES/EBU outputs.
The AES/EBU source must be stable before putting the unit in-line. If your AES/EBU source's clock rate
changes, or if the AES/EBU is disconnected, or if the AES/EBU audio source is turned off while the BD500 is
processing audio (in-line and powered on), the BD500 may add artifacts to the audio, or may indicate a failure
with an error message.
The BD500's purpose is to store audio and play it back with a delay. If the rate of audio into the unit changes
while audio is stored, the audio played from the delay will change pitch. Thus if the AES/EBU source's sample
rate changes or stops altogether (cable is disconnected), the BD500 may play out audio with a significant pitch
shift! If the unit falls back from AES/EBU to analog input at a different sample rate there will be a pitch change
in the audio already delayed through the unit. Your digital system must be set very close to either 32000 or
48000 samples per second or using the fallback option in the BD500 will allow several seconds of pitch changed
audio to pass.
If the AES/EBU clock rate changes drastically the BD500 may drop some audio, even while at 0 delay. If
this happens many times over a short interval, the BD500 will assume that something is wrong with the hard-
ware and will display an error message. If the clock rate goes over 48000 samples per second the unit will
display a message that scrolls across the display with the text " GLITCH ."