Classe Audio CP-500 - Manual (Page 24)

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rotary Th e rotary knob on the front panel does not directly control the volume.
Instead, it controls circuitry that does so with greater fi delity and precision than
traditional volume potentiometers could ever achieve.
Since the volume control circuitry is under software control, it is possible to
customize its behavior under various conditions. To better understand why this
is so valuable, consider two scenarios:
Person A places a high value on precision in achieving exactly the
volume setting that makes the music most realistic; being able to
easily change volume setting by a fraction of a decibel is critical to his
enjoyment of the system.
Person B just wants to jump easily from low volumes to a reasonable
listening level, and is less concerned with the fi ner points of precision
than with getting what he wants with a quick twist of the knob.
You can see the problem in these scenarios: Person A wants extremely fi ne
gradations on the volume control, which will require many rotations to go from
extremely low setting to normal listening levels; Person B wants to get from one
to the other with a “quick twist” of the knob, requiring coarse gradations in
order to cover so much range in so little space. What happens when Persons A
and B live in the same house? Or if Person C wants to have both, depending on
their mood at the moment? (In fact, most of us are probably like Person C.)
Classé solves this dilemma by altering the response of the volume control, based
on several factors.
Since it is rare to listen at extremely low (barely audible) volumes, the low range
adjustment of the volume control allows for faster response to knob input when
the volume setting values are low. When activated, you will get from extremely
low to middle volume control settings a bit faster than you would otherwise.
Th
is eff ect can be subtle, and may not even be desirable when the speakers used
have extremely high sensitivity (since this results in using the lowest part of the
range more than you would otherwise).
Th e most signifi cant factor in the perceived responsiveness of the volume control
is the speed at which the knob is being turned. We all naturally tend to move
volume knobs more quickly when we need to make a bigger change, and we
tend to slow down as we approach our desired volume. Th
us, if the CP-500 sees
the knob moving relatively quickly, it uses coarse steps to eff ectively accelerate
the action of the circuitry. As the knob begins to turn more slowly, the CP-500
will actually increase the resolution of the steps, which slows down the action
of the volume control and yields greater precision in choosing an appropriate
setting.
Of course, it is possible to bump into the knob by accident, which might
result in its spinning very quickly indeed. Rather than increasing the volume
uncontrollably under these conditions, the CP-500 actually slows everything
down again as a safety measure against accidentally blowing your speakers. In
fact, if you like you may establish a speed limit beyond which the knob will
simply be ignored.