Apogee APL-220, Руководство пользователя

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The power supplies are robust and reliable. They each provide 650 watts of
continuous power, giving the system considerable headroom above its nom-
inal 500 WRMS per channel rating. Each of the two amplifiers is capable of
delivering 500 WRMS, and as much as
1 600 watts of instantaneous burst
power.
Why the large difference between WRMS and instantaneous power? WRMS
is a measurement that occurs over a long period of time and is limited by
many factors including thermal considerations. Instantaneous power is a sim-
ple function of the peak voltage supplied to the speaker driver and the
impedance of the driver. Apogee’s APL series' amplifiers use a 80-volt bus (V)
with a 4-ohm driver (R). The instantaneous power calculation is:
Pi = V
2
/R
or
80
2
/4 =
1
600W
An amplifier's ability to handle musical transients is a function of its instanta-
neous power capability.
When installing and using the APL-220, -500, or -800, some simple precau-
tions should be followed. These include:
(
1
) Maintain Proper Air Flow
The APL-220, -500, and -800 are convection-cooled devices. Convection
cooling is more dependable than forced air cooling because fans are often
unreliable and require high maintenance. Apogee's APL-220, -500, and -800
do not need filter changes to protect the circuitry from contamination by
dust and dirt. The aluminum heat sink mounted on the rear surfaces provides
primary cooling of the system. Care must be taken to locate the loudspeak-
er away from heat registers, heat-generating appliances, lighting equipment,
and any other apparatus that could raise the temperature of the nearby air.
The APL-220, -500
,
and -800 require unimpeded air circulation in order to
function properly (this is especially important when multiple units are used
in stacked and/or tight-pack configurations). The APL’s rear surface should be
located at least
1
2" away from walls and/or ceilings. Sunlight and artificial
lighting, especially of the high intensity or theatrical type, should never be
allowed to shine directly on the heat sink.
1 6
Installation