ACHERON OPERATING INSTRUCTIONS
17

AMPLIFIER COOLING SYSTEM

The Acheron uses a forced-air cooling system with two fans
(one variable-speed, ultra low-noise primary fan and one
reserve fan) to prevent the amplifier module from overheat-
ing. The fans draw air in through ducts on the front of the
cabinet, over the heat sink, and out the rear of the cabinet.
Because dust does not accumulate in the amplifier circuitry,
its life span is increased significantly.
When the Acheron heat sink temperature is below 42° C, the
variable-speed primary fan runs continuously at its slowest
speed with an inaudible operating noise. The primary fan
increases speed when the heat sink temperature reaches
42° C; the primary reaches full speed at 62° C and is barely
audible near the cabinet, even without an audio signal. If the
the heat sink temperature reaches 74° C, the reserve fan
turns on. The reserve fan turns on if:
■The primary fan has failed (check status immediately)
■High source levels are encountered for extended periods
■Dust has accumulated along the cooling path
The reserve fan turns off when the heat sink temperature
lowers to 68° C.
NOTE: In the unlikely event that the reserve fan
does not keep the Acheron heat sink tempera-
ture below 85° C, the unit automatically shuts down
until AC power is removed and reapplied. If the
Acheron shuts down again after cooling and re-
applying AC power, contact Meyer Sound for repair
information.

Dust and the Amplifier Module

Operating the Acheron in dusty environments, or for pro-
longed, intensive periods, may cause dust to accumulate
along its airflow path, thereby preventing normal cooling.
Under these circumstances, it may be necessary to periodi-
cally remove the air intake foam and use compressed to air
to clear the dust from the foam and air ducts.
In addition, if the amplifier gets unusually hot, you should
remove the amplifier module and use compressed air to
clear any dust from its heat sink.
CAUTION: Make sure to unplug the AC power
from the Acheron before cleaning its amplifier.
CAUTION: To keep the Acheron from getting
too hot, allow for proper ventilation, 3–4
inches, behind the loudspeaker.
Airflow for the Acheron
Heat sink/
amplifier
Air filter
Power
supply
Air
intake
Low-
noise
fans
!
!