C250 amplifier, producing a much more
rich and open sound.
Having a Power Plant built into the Clas-
sic 250 to regenerate a clean AC signal for
the input gain stage is one of the factors
that sets this amplifier apart. It is worth
noting, however, that the Power Plant is
only regulating the input stage. Therefore,
additional levels of AC regeneration can be
implemented to improve the amplifier as
a whole, for example with a P1200 Power
Plant. In other words, a clean, well regu-
lated AC power line will make a difference
with the C250.
The X1 output current stage
Typically the output stage of a power
amplifier is tied to the input stage and
together they form a “team” to produce the
power. Not so in the C250. This revolu-
tionary and one-of-a-kind current stage is
an absolutely separate and independent
standalone current converter. It has its
own power supply, its own feedback loop
and is physically separated from anything
else in the amplifier.
The C250 can handle loads less than 2
Ohms and still breathe easily. To accom-
plish this we incorporated 20 high current
output devices per channel. Each of the
40 output devices in the Classic 250 can
handle 30 amps of power.
The main power supply
Obviously the purpose of a power ampli-
fier is to generate power. Pure, clean and
musical power that has no limitations.
Inside the C250 are two completely inde-
pendent toroidal transformers and power
supplies and a short signal path to main-
tain the highest possible power quality.
Each of the two toroidal supplies is a mon-
strous 800VA transformer that is housed
under its own chassis, isolated from the
main body. These transformers feed a
robust 80,000 mFd’s of energy storage.
Operation
Front Panel: Power
The front panel of the C250 was designed
to bring both a level of elegance and sim-
plicity into your system. The power button
(on/off) is located directly in the center,
below the meter display.
Plugging the C250 into the wall activates
both the regenerator (power plant) and
voltage gain (input) stage. The meter dis-
play will light up in yellow for 17 seconds
while these two circuits activate, during
which the power button will not respond
to your touch. These sections are kept
powered up at all times. After the initial 17
second activation period, the yellow light
in the meter display will go dim. Still, the
output section has no power.
Pressing the power button will initiate the
power up sequence, which lasts for 40
seconds. During this period, the meter will
light up in yellow and the PS logo in blue,
indicating the standby status. It is not
advisable to try and play music during this
period.
The C250 becomes fully operational once
the meter display lights up in blue. This
indicates that the C250’s output stage is
engaged. Once fully powered up, pressing
the power button again will turn the output
stage off.
Front Panel: Display
The front panel display window in the
C250 contains an analog meter that reads
several useful statistics.
The top line, labeled “DCV,” is a represen-
tation of the voltage that is available to the
output stage. There is a direct relationship
between this value and the input AC volt-
age. For example, feeding the C250 with
120 volts should present a DCV value of
80 volts.
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