Idiomas disponibles
Idiomas disponibles
The SM-500 takes up two full rack spaces (3 1/2"). If the rack in which you mount the SM-500
requires that the rubber feet on the bottom of the chassis be removed, please remember to
REPLACE the screws, as they help to reinforce the chassis.
The SM-500 should be mounted as close to the bottom of the rack case as possible. The height
of the rubber feet was chosen so that when you slide the unit in the bottom of a rack case, the
rack mounting holes on the front panel should line up with the mounting holes of the rack rail.
This prevents the SM-500 from flexing downward if the rack case is dropped. If you must mount
the SM-500 in an area of the rack other than the bottom space, a piece of wood or similar solid
material should be installed between the bottom of the rack case and the bottom of the amplifier
to prevent flexing of the amplifier's chassis. Severe or constant flexing of the chassis can dam-
age the amplifier and is not covered under the SM-500's warranty.
Don't neglect your amp after it's been installed in a rack case. Continuous transportation and
vibration can cause screws to become loose, both on the SM-500 and with your rack case rails.
We recommend that at least once a month you remove the SM-500 from the case and tighten all
outside screws (especially on the front panel), and wipe off the outside of the chassis with a
damp cloth. Then check all the connections in your rack case and reinstall the unit.
POWER-ON TRANSIENT
When the SM-500's Power switch is moved to the "On" position, you will notice a turn-on tran-
sient heard as a "thud" through your speakers. This will not harm speakers made by SWR, howev-
er, you may connect your speaker cable to the SM-500 after powering up if you choose. Just
make sure you are not playing through the unit when you make the connection, as it could cause
a speaker fuse to blow. Eliminating this transient would require a component called a relay. SWR
chose not to incorporate this type of component due to the fact that relays degrade signal quality
and often fail, causing the unit to have no output, and requiring a trip to a local service center.
A FEW WORDS CONCERNING HEAT
One of the most asked questions about our amplifiers is why they tend to get warmer than other
amps. The chassis of your amplifier can get quite warm during normal usage. This is especially
true if you are using a 8 ohm total impedance in the Bridge mode. This is because a 8 ohm
impedance (or 4 ohms per channel in Stereo mode) introduces the least efficient condition of the
unit (in other words, power drawn from the outlet in relation to power produced in the speakers).
The difference in these two figures can be quite high, resulting in the equivalent of a high wattage
light bulb in a metal box (which would obviously get quite hot).
Most musical instrument amplifiers on the market today use steel for their chassis which, in
most cases, is considerably cheaper than aluminum and does not conduct heat as well as alu-
minum. The SM-500 uses an all aluminum chassis because it has less impurities than steel, is
less susceptible to rust and is a better conductor of heat. This results in the chassis acting as a
heatsink drawing heat away from heat producing components inside and thus extending their life.
In this manner, we feel we have produced a more reliable amplifier, but, at the same time, the
outside of our units will get warmer than cases made out of steel.
You should be aware of the possibility of the power amp in your SM-500 becoming "over biased."
This condition can be recognized by turning your amplifier on and letting it sit without speakers
plugged in and without playing it. If, under these conditions, your unit becomes quite warm, it may
be over biased. This situation should be attended to and can be easily remedied in about 15 min-
utes by a service tech. A power amp can become over biased through continuous vibration or by
any large jolt received in shipping, transportation, etc.
16 • SM-500
