Mark Levinson 433 User Manual

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Nº433 Power Amplifier
Special Design Features
Thank you for purchasing the Nº433 Power Amplifier. While this 
amplifier is straightforward in everyday use, it includes several 
design features that are responsible for its outstanding performance. 
In particular, this amplifier defies the accepted wisdom that it is 
impossible to design a large, powerful amplifier that also has all the 
finesse of the finest smaller amplifiers. A few of the technical 
highlights that make this possible are described below.
Massive Power Supply
The Nº433 features three large, robust power supplies. Each supply 
includes a high-capacity, low-noise toroidal transformer, and two 
large, low ESR (“Equivalent Series Resistance”) capacitors.
Heavy oxygen-free copper bus bars enhance the efficiency of power 
distribution within the amplifier and eliminate variances intro-
duced by the wiring harnesses that are commonly found in lesser-
performance amplifiers. High-frequency power supply bypass is 
accomplished on individual PC boards by components of several 
film types. The resulting uniformly low power supply impedance 
seen by the various circuits within the amplifier lays the foundation 
for the massive power delivery and extraordinary finesse that 
characterizes Mark Levinson amplifiers.
Balanced Design
A truly balanced input topology eliminates the need for an input 
buffer amplification stage, allowing the first stage differential 
amplifier to be driven directly by the source. Matched impedances 
are presented to the source. Both signals travel through identical 
circuit paths. 
Meticulous attention to the layout of the amplifier, including 
careful mirror-imaging of circuits to cancel magnetic fields, 
minimizes magnetic field distortions that can occur with a massive 
power delivery system. A balanced input signal remains balanced 
throughout the voltage gain stages. Rejection of common mode 
noise and distortion is achieved in the final, current gain stage.