| Four independently
rectified and filtered voltage rails! The power supply of
any component is the foundation of the device. Everywhere
the signal goes, it sees the power supply. Any noise,
crosstalk, or spurious voltages in the power supply will
ultimately leak into the sound. Once you introduce garbage
into the sound, there is nothing you can do to remove it.
The
Model 18b starts with two different transformers: an alloy core for the digital circuits,
and a low emission torroidal for the
analog circuits. These specialized ac waveforms are then converted to DC
voltages by four independent rectifiers, each with their own
filter capacitor and shunt capacitors. This creates four
completely isolated DC voltage rails, whose oscilloscope pattern
is every doctor's worst nightmare - an absolutely flat, flat line.
This design completely isolates the digital circuits from
the analog circuits, while providing each with the specialized
type of power they need. Smart, very smart.
Now
that the unruly ac power has been cleansed and sterilized, let's
see how it is put to use.
The
digital duo...
|
