MARK LEVINSON No27L

Commentary

This stereo power amplifier was developed based on the know-how obtained in the development process of No23L.

A dual monaural configuration is adopted in which the left and right sides are completely separated from the power transformer.
Two toroidal transformers and a total of 45,000 μ F capacitor are used in the power supply section, and power is supplied to the power transistor at the shortest distance by the oxygen-free copper bus bar.

The voltage amplification stage consists of two stages of cascaded transistor differential amplifiers and a discrete stabilized power supply circuit. The current amplification stage consists of three stages of Darlington SEPP.

We studied the circuits required for power amplifiers from Mark Levinson's unique point of view. The input impedance is constant at 50k Ω over the entire band and does not vary, and the internal impedance of the output stage is sufficiently low.

A π - type high-cut filter and -cut filter and a DC-cut capacitor are inserted into the input terminal, and a line filter is inserted into the AC line.

Equipped with a surge limiter circuit to protect the power supply parts from large current when the power is turned on, and a protection circuit to protect the output stage of the amplifier and the speaker unit from damage.

In addition to the normal input via the CAMAC connector, the balance input via the Canon connector is incorporated.

Bridge connection allows for use as a high-power monaural amplifier.

Model Rating

Type	Stereo power amplifier
Configuration	Dual monaural configuration
Rated output	350W + 350W (2 Ω) 200W + 200W (4 Ω) 100W + 100W (8 Ω) 700W (4 Ω, bridge connected) 400W (8 Ω, bridge connected)
Frequency characteristic	4 Hz to 140 kHz -3dB
Signal-to-noise ratio	106dB
Input impedance	50k Ω
Pwer	100 VAC, 50Hz/60Hz
Power consumption	175W (idle) 400W (8 Ω, at rated output)
External dimensions	Width 483x Height 175x Depth 450 mm
Weight	31.5kg