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shown here. Just like the stereo
width enhancement, the lighted area
in the OLED and numbers in both lo-
cations are arbitrary and relative.
Use this enhancement technique with some caution. A hawker
of toilet tissue who seems to fill the listener’s automobile may
be a bit intimidating to driver and passengers alike!
Stereo enhancement effects can be subtle, depending in large
part on program source. In making these adjustments, switch
between
Active
and
Bypass
in judging the action. This will make
changes more clear than simply moving the sliders back and
forth. Keep this in mind also: seasoned broadcast engineers
concur that overuse of stereo enhancement techniques exacer-
bate FM multipath effects… and make them worse, too!
THE FIVE-BAND ‘MULTIPRESSOR’
The heart of DAVID IV’s dynamics processing is the 5-band
Multipressor (Multiband Compressor). This processing block
divides the program audio into five discrete frequency bands
with nominal crossovers and filter slopes optimized for each
range of frequencies. Each band undergoes dynamic range
compression, with the threshold, waveform response and trans-
fer function engineered for the most effective action within
each band.
Optimum Multipressor parameter settings were derived from
exhaustive tests by a core of listeners comprising both tech-
nical and non-technical types, including those with extensive
musical training. Many of these parameters are fixed, as
providing user control over the thousands of parameter permu-
tations would make setup a veritable nightmare… not the ob-
jective of this product. Some parameters, those that most read-
ily define ‘sonic signature,’ have been made available for user
adjustment over a reasonable range.
Compressor
Drive
Master Drive (dB):
varies the total signal level going into the
DAVID IV multiband compressor section. The setting of this
control determines how hard the compressor will work, overall,
and to a large extent how ‘busy’ or dense the program will
sound. Incidentally, density is only one factor affecting per-
ceived loudness. Additional discussions on the subject of
loudness follow in due course.
Master Drive (dB):
has been afforded a very wide range. At the
minimum setting of 0dB, program material may not even ‘tickle’
the compressors, giving no visible indication of gain reduction
(G/R) in any band. Advanced all the way to 30dB, all five bands
will probably be dancing down close to the bottom of the bar-
graph displays.
Содержание DAVID IV 719 N
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