Specifications
11
Operating Manual - ne24.24M Matrix Processor
be crystal clear sound directly in front of any one loudspeaker can be unintelligible at the farther reaches of the venue with direct
line-of-sound to multiple loudspeaker sources.
The solution is to delay the audio signal to the loudspeakers located further away from the primary source, so that
sound comes out of the distant loudspeakers at the exact time that sound from the main loudspeakers arrives. Within the Protea
ne24.24M, up to 682 milliseconds of time delay are available on each input channel, allowing secondary loudspeakers to be
time aligned with the primary speakers up to 771 feet (235m) away. Set the TEMP text box to the current air temperature to get
the most accurate display of delay distance.
Fine tuning delay settings is accomplished using the <up/down arrows> on the keyboard. Course changes of 1mS are
quickly accomplished using <PageUp/PageDown> buttons.
8.1h Input EQ
The Protea ne24.24M input EQ section offers 15 custom
lters per input. Types of lters available for each band include
parametric, 1st order and 2nd order low shelf, 1st order and 2nd
order high shelf, and all-pass.
Shelving EQ lters: 1st order lters use a gentle 6dB
per octave slope, while 2nd order lters use a 12dB per octave
slope for a more pronounced boost or cut. All shelving lters
have a boost/cut range of +/-15dB. Low shelving lters have a
frequency range from 20Hz through 2kHz, and the high shelv-
ing lters range from 3.886kHz through 20kHz. Shelving lters
are most useful as broad tone controls to boost or cut the high
end or low end of an audio signal’s frequency content. Because
they affect a wider spectrum of audio, they are not as suitable for
feedback control as parametric lters. Course and ne tuning of
shelving lters can be performed using <page up/page down>
and the <up/ down arrows> on the keyboard.
Parametric EQ lters: These are peak lters with the
ability to control boost or cut, frequency center, and bandwidth,
also called “Q” for this type of lter. Think of one band of
parametric EQ as a single graphic equalizer fader except that
the frequency is variable, not xed, and that the bandwidth, or
how “wide” the lter affects the frequency spectrum at the center
frequency, is completely variable. The smaller the bandwidth
(higher Q), the less the audio signal on either side
of the frequency center is boost or cut, whereas
a larger “wider” bandwidth (lower Q) produces
an audible change to the overall tone of a signal.
Parametric lters are best used to hunt down and
eliminate problem feedback frequencies, add or
remove a characteristic “hot spot” from micro-
phones, or clean up room resonance situations. It
is well worth the time becoming procient with
parametric EQ lters, as they offer the best solu-
tion to many EQ problems.