Eventide H7600, Руководство по эксплуатации

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Eventide H7600 User Manual 53
input. If any external input is used as an audio source, it must have identical sample
rate as the system sampling rate, or one or more of the digital values may be lost.
This results in unwanted clicks or distortion. For example, at a sample rate of 96
kHz, an 0.001% difference (10 parts per million – more accurate than most clock
sources) will likely create a faint click every one second or so.
A very small difference in sample rates results in slipping , meaning that the sample
points “slip” past each other in time. The amount of slipping correlates directly to
the quality of your output. The results may be inaudible (slight clicks will be
masked by the signal) but its effects are always negative.
Since it is unlikely that pure chance will allow any two or more external signals to
have exactly the same sample rate, it is necessary to
synchronize
(lock) them,
meaning that the external signals derive their sample rate from some common
reference. This may be either a signal from the H7600 itself, or an external signal
feeding the H7600. It is good practice to establish a central, high-quality clock
source to which all the digital audio equipment is synchronized.
The H7600’s digital inputs incorporate optional sample rate conversion , where
new digital values are created to fill the gaps caused by sources with different sample
rates.
Using the Internal Clock
When you use the H7600’s internal clock, the system sampling rate will correspond
with the internal clock’s sampling rate.
The system sampling rate is the sampling rate used for all internal processing. If
you’re using the digital inputs while the system sampling rate is set to an internal
clock source, you must ensure that the clock of the machine being input to the
H7600 is synced to the H7600’s digital output.