Nº32

The Nº32 Preamplifier is a revolutionary Mark Levinson component. It is the first preamplifier to earn the Reference label.

Separating power-supply and control circuitry makes sense in a modern, Reference-level preamplifier. AC power supplies, microprocessors, LED displays — essentially, anything that generates noise — are housed in a separate chassis from the low-level audio signals (the Nº32 Reference Controller), while all of the audio-preamplifier circuitry is housed outboard (the Nº32 Reference Preamplifier). Thus, the audio circuits are exposed only to quiet, regulated DC power and the audio signal itself.

Two master power supplies are located in the center section of the Reference Controller: one is dedicated to control and communications; the other is used for the audio circuits. The power from the AC line is pre-filtered, and the two master supplies are isolated from one another. The power supplies use custom-designed transformers featuring multiple secondary windings, which substantially improve isolation between separate circuit blocks. Separate rectification, filtering, and regulation circuits are used to supply DC to the control/communications circuits, a Nº25 phono DC supply output, and the 400Hz oscillator circuits used in power-supply regeneration.