Mark Levinson Model 20
A pair of Mark Levinson No. 20 Monoblock
was brought into our store with a very high noise level in 1 channel.
It failed our bench test on distortion, stability and S/N Ratio.
Diagnostics revealed faulty transistors
and zenar diodes which were replaced. The bias was
re-adjusted, and the amplifier was burned in for 48 hours.
The repair was successful, and bench test
met factory specification.