Power Supply - SPL DynaMaxx 9735 User Manual

Special care has gone into the design of the power supply of
the D M because the power supply is the heart of any elec-
YNA AXX
tronic system, and the better it is, the better the whole system
works. In an audio system, this translates into better sound
quality, lower noise and lower distortion.
The power supply is based around a 15 VA torroidal transformer
and is designed to minimize induced hum and noise due to the
lack of an air-gap.
The primary voltage may be selected between 230V/50 Hz and
115V/60 Hz by means of a recessed slide switch on the rear panel
and a rear panel ground-lift switch is fitted for use where ground
loops are causing hum problems. When the GND LIFT switch is
depressed, the circuit ground is isolated from the chassis ground.
The detachable power cord is a standard 3-wire type fitted with
an IEC mains connector; the transformer, power cord and mains
connector have VDE, UL and CSA approvals.
The fuse has a value of 315 mA.
On the secondary side of the power supply, an RC combination
is used to filter out noise and hum voltages. Both half-waves are
smoothed with 10,000 microF capacitors in the positive and
negative supply path, and both lines use precision voltage regu-
lators for optimum stability. Deviations of only a few millivolts
can impair audio quality, introducing artifacts such as loss of
stereo imaging or a diffuse sound character.
Particular care has gone into the circuit layout and component
choice to minimize crosstalk between the audio circuitry and
control voltages.
DynaMaxx

Power Supply

Torroidal transformer
Voltage selector
Ground-lift switch
Transformer, power cord and
mains connector with VDE, UL
and CSA approvals.
FUSES (primary voltages):
115 V: 800 mA
230 V: 315 mA
Positive and negative voltage
paths are smoothed with
10,000 mF capacitors
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