BSS Audio
DPR-402 User Manual v3.0
Page 13
10
.3 Attack Time
The response of the
DPR-402
compressor to signals above the threshold point is
further defined by the ATTACK TIME control.
The
DPR-402
ATTACK TIME control has 11 calibrated positions from 50
microseconds to 100 milliseconds, and determines how quickly the compressor
responds to signals once the threshold is exceeded.
As explained earlier, for fast transients, a fast attack time is desirable. For other
types of program material a slower time will be more useful. It is always preferable
to start with a slower time, and progressively speed up the response as necessary,
since too fast a time may cause distortion of the sound.
10
.4 Release time
Another parameter which affects the compressor performance is the RELEASE TIME
control.
The release time control has 10 calibrated positions from 5 milliseconds to 5
seconds, and determines how quickly the compressor returns to normal gain
following a transient in excess of the threshold. The setting of the release time is
very much dependant on program type, and the setting of a wrong speed will result
in either of two conditions:
If set too fast; the overall volume level will jump up and down, exactly following
the peaks above threshold, and this will produce an objectional and unsettling
effect.
If set too slow; quiet parts of the program immediately following loud transients
will be subjected to 'breathing' or 'pumping' effects caused by the VCA releasing
its attenuation (or effectively the system gain) during the quiet program period,
when it is not required.
10
.5 AUTO TIME
This feature of the
DPR-402
is provided to overcome some of the settling problems
associated with the attack and release time control features. It is accessed by
switching the released time control to the 'AUTO' position, whereupon the circuit
automatically adjusts itself to provide the required attack and release time settings,
depending on the program type.
The circuitry combines a program related attack time setting and a two part
program related release time setting. The two part program dependant release
provides:
A fast release to restore below threshold gain as soon as the transient has passed.
A much longer following release to avoid rapid gain change effects.
