coil bottoming out makes a lot of noise, and
if they don’t notice that, the loudspeaker
blowing apart shortly thereafter is a sure
indicator.
over-heating, on the other hand, is not
very well understood or simple to measure
and document. Think of the loudspeaker’s
voice coil as if it were a space heater: apply
a certain amount of voltage, and the coil
heats up. Very little voltage produces very
little heat. A lot of voltage will produce a
lot of heat, until the voice coil is producing
more heat than it can handle and burns
up. Unlike a room heater’s glowing red
element, a loudspeaker voice coil is made
of fine, fragile wire. To help it survive the
kind of power we expect in pro audio, the
voice coil is cooled both by sinking heat
into the magnet assembly it rides in, as
well as by pumping cool air around the
magnet structure through the motion of
the cone. Modern voice coils can handle
a great deal of heat, but there are still very
definite limits. see Exhibit 3.
Exhibit 3 - Jim Bowersox.
CREST FACTOR
what complicates the amount of heat a
driver can take is something called “crest
factor.” The crest factor of a waveform is
the ratio of its peak amplitude to its RMs
value, which can be expressed in dB. A
pure dC signal has 0 dB crest factor. A
pure sine wave has 3 dB crest factor. Pink
noise has a crest factor of 6 dB. Any two
signals that have identical RMs values will
create the same amount of heat, but the
one with the higher crest factor will have
higher peak amplitude, which can make a
large difference in the way it sounds. Most
importantly, live music commonly has a
crest factor around 20 dB, 100 times more
peak power than RMs!
This crest factor is the reason that
loudspeakers and components are
XP Series Professional Syste
m Controllers
Smart and Cool, Just like You.
XConsole
Ethernet
Supplied with XConsole GUI
2x4, 3x6, 4x8 and 8x8 in-out configurations
Precise DSP algorithms
Excellent audio quality, 96 kHz- 40 bit floating point DSP
Up to
16 devices in the same network
31bandsEQoneachinput,8bandPEQoneachinputandoutput
650ms delay,
30 presets, password protection
Connectivity over RS232, USB and Ethernet (wireless ready)
Also available with Microphone inputs (M Suffix)
Options: XPanel remote wall controller
