Electro-Voice 1700 Series Operating Instructions Manual page 5

Don't let the thermometer bulb touch the metal
chassis. The chassis might be hotter than the
ambient air.
If the air temperature exceeds 60°C (140°F), place
the equipment farther apart or install a blower to
provide air movement within the cabinet. Make sure
you don't block the air intake holes located on the
bottom of the chassis or the exhaust holes on the
top cover.
Figure 5 above displays a block diagram of the mixer/power
amplifier mainframe. Study it carefully. To use the system's full
capabilities, you'll need a good understanding of the inner
workings of the mainframe. Brief explanations of how the inside
of the mainframe works follow in the text below.
The signal coming from each additional input module
simultaneously routed to the mixer/power amplifier's front-panel
nominal/peak LED indicators and to the input channel level
Figure 5. Block Diagram of 1707C / 1715C Mixer/Power Amplifiers
CAUTION
CAUTION
controls. The dual LED nominal/peak displays are pre-fader and
designed to monitor the output level from the corresponding
input module. The nominal (green) LED indicators have an
approximate 10 dB window over which they will illuminate. This
makes it easy to properly adjust the gain for each input module
while efficiently using the rest of the system in terms of
performance and headroom.
The mixer/power amplifier then sums the signal at the wiper of
each input channel level control into a true virtual ground
summing node or bus. The summing amplifier has eight input
channels - input channels one through six on the front panel,
tone generator output, and the link input or LINK IN on the rear
panel. The summing amplifier's output signal drives the link
output, or LINK OUT, located on the rear panel of the mainframe.
The E.Q. and compressor/limiter sections are in series with each
other, as shown in Figure 5. The compressor/limiter's output
signal drives the preamplifier output, or PREAMP OUT, located
on the rear panel which then provides the input signal to the
main amplifier section.
The BASS and TREBLE E.Q. controls are ideally suited to make
adjustments to the overall response of the mix. The low and
high frequency shelving equalizers provide ±12 dB of boost
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