Power Amplifiers

Mark Levinson No 53 Monoblock Power Amplifier

ARTICLE INDEX

Introduction

Mark Levinson is a state-of-the-art brand, whose products are purchased by consumers whose bank accounts are also state-of-the-art. Levinson makes no apologies for their prices, nor do they have to justify them. The axiom is simple: If you want the best, it costs a lot. The latest addition to their power amplifier line takes a huge leap from the previous designs, which were Class AB, and which usually were biased well into Class A operation. The Mark Levinson No 53 is a monoblock power amplifier that is a switching design, i.e., the output stage is operated in switching mode, but it is unique in that it interleaves eight switchers (Levinson calls it Interleaved Power Technology, or IPT) to produce a fully balanced output, at a realized switching frequency of 4 MHz.

It weighs 135 pounds, which, at first, surprises those of us who are familiar with switching amplifiers. They usually are very light weight, due to their efficiency.

Specifications

  • Design: Solid State Monoblock Power Amplifier; Switching Output Stage
  • Power: 500 Watts RMS into 8 Ohms, 1,000 Watts into 4 Ohms
  • MFR: 10 Hz - 20 kHz, ± 0.1 dB
  • THD+N: Not Specified
  • S/N: 85 dB (@ 1 Watt into 8 Ohms)
  • Inputs: XLR and RCA
  • Input Impedance: 100 kOhms Balanced (XLR), 50 kOhms Unbalanced (RCA)
  • Outputs: Two Sets of Speaker Binding Posts for Bare Wire or Spade Lugs
  • Other Connections: Ethernet, Link Port (connection to othe Levinson products), Trigger
  • Dimensions: 20.4" H x 8.4" W x 20.4" D
  • Weight: 135 Pounds
  • MSRP: $50,000/pair USA
  • Mark Levinson

The reason the No 53 weighs so much is that it uses a conventional power supply. The switching occurs only in the output stage. The power transformer is a 2.8 kVa toroid, and there are 188,000 µF of power supply capacitance. There is an additional 106,500 µF of local capacitance for circuits other than the rail voltage.

The amplifier is rated at 500 watts RMS continuous output into 8 ohms and 1,000 watts into 4 ohms. It is capable of delivering short transient power levels much higher than the rated output.

The rear panel has the inputs near the top, both RCA and XLR, plus an Ethernet port for communicating with other Levinson equipment in your home network, a port for direct hard wire communication with other Levinson products, and a trigger. There are two sets of speaker binding posts that accept bare wire or spade lugs. The hole that would otherwise accept banana plugs is blocked with a plastic insert. The on/off toggle switch is at the bottom, and you can put the amplifier in two states. One is that the power button on the front panel switches the amplifier from a cold start off, or from a warm standby, selectable with a switch on the top of the rear panel.

A close-up of the networking jacks is shown below.

mark-levinson-no-53-power-amplifier-photo-rear-panel-closeup