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Special Design Features
Thank you for purchasing the Nº 320S Preamplifier. A direct
descendant of the Nº 32 Reference Preamplifier, the Nº 320S
features audio circuits, controls, architecture, and optional phono
modules based on the critically acclaimed Nº32. In fact, some
audio circuits, such as the proprietary discrete volume attenuators,
are identical to those found in the Nº 32.
With a single-chassis design, the Nº 320S achieves separation of audio
circuit, control circuit, and power supply sections similar to that of
the dual-chassis Nº 32. The internal structure of the Nº 320S separates
these sections, while a steel shield box protects the power supply
and other circuits against electrostatic and magnetic interference.
Filtered AC power is routed outside audio circuit sections, providing
audio circuits with the quiet, shielded environment essential for
superior sound.
Like most high-performance audio components, the Nº 320S relies
on clean, noise-free AC power to deliver maximum performance.
Unfortunately, most AC power does not meet these standards.
Common household appliances such as refrigerators, TVs, and
computers often contaminate AC power lines with line noise,
spikes, and other irregularities that make it difficult for audio
circuits to perform up to their full potential.
To compensate for this, the Nº 320S offers a series of highly effective
noise suppression and isolation techniques that begin filtering AC
power for noise as soon as it enters the chassis. Audio and control
circuit sections use independent power supplies, each with its own
low-noise toroidal transformer. The audio circuit power transformer
includes a Faraday shield between the AC power line and low-
voltage secondaries for improved isolation.
In addition, the Nº 320S uses two active voltage regulation stages
for audio circuit sections. A high-power stage absorbs line-voltage
and temperature variations, while a second high-performance
stage provides local, high-speed, low-noise power for audio
circuits.
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Getting Started
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