.
Once one side of the grille is located, the other side of the grille can
be forced into place. This requires a bit of pressure because the
grille must be forced back into its curved contour. When both edges
of the grille are seated against the face, the socket head screws of the
clamps can be re-tightened. If they were loosened five full turns to
remove the grille, then five full turns will be sufficient to re-clamp
the grille. The clamps should not be over-tightened; they should
only be tightened sufficiently to engage and secure the grille. This
can be checked by hooking the short arm of the key through the
grille near the clamp and pulling upward. Once the screw is
tightened to the point that the grille does not move when it is pulled
up with the key, the clamp is sufficiently tightened.
11
WHAT AMPLIFIER SHOULD YOU USE?
There are several things you should keep in mind when selecting an
amplifier. First, you need an amplifier with enough output power.
Even if you are not planning to run your system very loud, an
amplifier needs to have enough power so that the dynamics of
speech and music will not cause “clipping.” An amplifier that is
pushed beyond its output power capability will clip signals. Not
only does this sound bad, but the effect on a low frequency speaker
or mid or high-frequency driver is similar to hitting the cone or
diaphragm with a hammer. Because of this,
too small an amplifier
can be more damaging to speakers than one that seemingly has too
much power.
Peaks in speech or music signals can easily exceed the
average power levels by a factor of ten. If your amplifier is not big
enough, these peaks become clipped and distorted.
So how many watts can this baby handle?
You’ve heard this question a thousand times. The answer is “it
depends on the thermal/mechanical limits of the drivers and
crossover components.” It also depends on the input signal, its
peak/average ratio, rise times, and spectral (frequency) content.
Actually the question is not what is the power handling, but what is
the OPTIMUM power to use? For Community loudspeakers the
best answer lies in the PROGRAM power rating. This is the size
amplifier you should use. If you can’t find an amplifier with that
exact rating, multiply the PROGRAM power rating by .80 and again
by 1.25 to find the recommended power range. For example, the
range for a 500W PROGRAM power rating is from 400W (.80 X 500)
to 625W (1.25 X 500). Anything larger is potentially excessive.
Anything smaller can cause damage. The amplifier will clip before
activating the Thermal-Link™ thermal protection circuits.
Our RMS rating represents the thermal power limit for the
loudspeaker. It is also a standard number for comparing to other
products. The impedance or speaker load the amplifier "sees" is very
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