doughnut shaped transformer commonly used in electronics,
speand amplifiers in particular for its low noise, low resistance
to current flow, and power output for its size. Most good
quality amplifiers use toroidal transformers.
in general are used to capture power from a wall outlet
and convert it to a high-power supply that can be used by
the amplifier or electronic device. The transformer is one
of three pieces in a power supply. The rectifier follows
the transformer and turns alternating current into direct
current. The final pieces of the power supply, the capacitors,
store energy for latter use by the amplifier or electronic
quality power supplies need high-capacity capacitors and
large, powerful transformers. The transformer should be
able to output several times the maximum power output of
the amplifier to the speakers. Thus if the peak power of
an amplifier is 300 watts, the transformer should be able
to output 600 to 900 watts of power. This may be less if
the amplifier is class AB, or it may be more if the amplifier
is class A.
transformers generally weigh around a pound for every 30
watts of output they can produce. Thus a toroidal transformer
capable of outputting 600 watts would weigh around 20 pounds.
Transformers must be large and necessarily heavy to output
large amounts of power for high-powered, high-quality amplifiers.
Amplifiers claiming 500 watts output but weighing only 15
pounds should generally be avoided assuming they must have
a poor power supply. While an amplifier's weight is certainly
not its defining characteristic, most amplifiers with good
quality power supplies are fairly heavy thanks to a large
toroidal transformer. The transformer and the power supply
are vital to a well-designed, well-built amplifier (or any
other electronic component).