Madrigal Imaging N33 ユーザーズマニュアル
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Special Design Features
Congratulations on your purchase of Mark Levinson Nº33 Reference Monaural
Power Amplifiers. While your new amplifiers are straightforward in their everyday
use, they include several design features which are responsible for their outstand-
ing performance. In particular, the Nº33 Reference Monaural power amplifiers
defy the accepted wisdom that it is impossible to design a large, powerful ampli-
fier that also has all of the finesse of the finest smaller amplifiers. A few of the
technical highlights that make this possible are given below.
Power Amplifiers. While your new amplifiers are straightforward in their everyday
use, they include several design features which are responsible for their outstand-
ing performance. In particular, the Nº33 Reference Monaural power amplifiers
defy the accepted wisdom that it is impossible to design a large, powerful ampli-
fier that also has all of the finesse of the finest smaller amplifiers. A few of the
technical highlights that make this possible are given below.
Massive Power Supply
The Nº33 incorporates two 2.45 kVA low noise toroidal transformers in a fully
balanced power supply. In this design, there is a separate power supply (each
with its own power transformer) for both the inverting and non-inverting halves
of the amplifier. Twelve 39,000
balanced power supply. In this design, there is a separate power supply (each
with its own power transformer) for both the inverting and non-inverting halves
of the amplifier. Twelve 39,000
µ
F low ESR capacitors are used in each amplifier.
The power supply of each Nº33 provides almost
1
⁄
2
a Farad of capacitance and
1200 Joules of energy storage.
Heavy oxygen-free copper bus bars enhance the efficiency of power distribution
within the amplifier and eliminate variances introduced by the wiring harnesses,
etc. more commonly found even in high performance amplifiers. High frequency
power supply bypass is accomplished on individual PC boards by a total of 56
components of several film types. The resulting uniformly low power supply im-
pedance seen by the various circuits within the Nº33 lays the foundation for both
the massive power and the extraordinary finesse that characterizes this amplifier.
within the amplifier and eliminate variances introduced by the wiring harnesses,
etc. more commonly found even in high performance amplifiers. High frequency
power supply bypass is accomplished on individual PC boards by a total of 56
components of several film types. The resulting uniformly low power supply im-
pedance seen by the various circuits within the Nº33 lays the foundation for both
the massive power and the extraordinary finesse that characterizes this amplifier.
AC Regeneration
In recent years, the detrimental sonic effects of noisy, unbalanced AC mains sup-
plies have become widely known. Various passive AC “line conditioners” are avail-
able for use with line level components such as preamplifiers and digital audio
processors to address these problems. In most cases, these line conditioners pro-
vide some filtering of the AC mains, along with some measure of surge protec-
tion. None of these devices may be used to good effect with power amplifiers,
however, since they cannot handle the large instantaneous currents which power
amplifiers require during normal operation. In effect, passive line conditioners
become a “bottleneck” in the otherwise free flow of power through the amplifier
to the speakers, reducing dynamic impact and musicality.
plies have become widely known. Various passive AC “line conditioners” are avail-
able for use with line level components such as preamplifiers and digital audio
processors to address these problems. In most cases, these line conditioners pro-
vide some filtering of the AC mains, along with some measure of surge protec-
tion. None of these devices may be used to good effect with power amplifiers,
however, since they cannot handle the large instantaneous currents which power
amplifiers require during normal operation. In effect, passive line conditioners
become a “bottleneck” in the otherwise free flow of power through the amplifier
to the speakers, reducing dynamic impact and musicality.
In the Nº33, a more sophisticated approach is used that provides greater line con-
ditioning benefits than the commercially available passive devices can hope to
provide, while simultaneously avoiding any performance “bottlenecks.”
ditioning benefits than the commercially available passive devices can hope to
provide, while simultaneously avoiding any performance “bottlenecks.”
A distortion-free 60 Hz sinewave is regenerated within the Nº33, and then used
to power a separate power supply dedicated to all the voltage gain stages. AC
power is delivered from the wall to the primary supply of the Nº33, where it is
rectified, filtered and regulated into positive and negative DC voltages. A portion
of this DC power is then used to drive an oscillator circuit which regenerates a
pure 60 Hz sinewave without any of the noise or contamination so common to
the AC mains as delivered to our homes by power utilities.
to power a separate power supply dedicated to all the voltage gain stages. AC
power is delivered from the wall to the primary supply of the Nº33, where it is
rectified, filtered and regulated into positive and negative DC voltages. A portion
of this DC power is then used to drive an oscillator circuit which regenerates a
pure 60 Hz sinewave without any of the noise or contamination so common to
the AC mains as delivered to our homes by power utilities.
The regenerated, pure sinusoidal AC wave is then sent to a dedicated secondary
power supply, where it is converted to positive and negative DC power to be
used by all of the voltage gain stages. This dedicated supply for voltage gain
stages benefits from having a truly balanced source (unlike the dissimilar imped-
power supply, where it is converted to positive and negative DC power to be
used by all of the voltage gain stages. This dedicated supply for voltage gain
stages benefits from having a truly balanced source (unlike the dissimilar imped-