legg a couché sur son écran :
On Mon, 15 Feb 2016 09:01:57 +0100, alpibucky
wrote:

Marantz superscope MS-30

I'd be surprised if the MS-30 had output transistors. These
multichannel all-in-one one units often just used a power IC for each
channel.

Sounds like you don't know if the output circuit is the actual
problem, here, or you'd be able to quote the part number from its
physical markings, on the assembly.

RL

Hello,

Thanks for the answers.
The MS-30 has a push pull stage with pair of transistors with their
bias mounted on the cooler. But I do not have the schematic. The
problem is distorsion in the left channel.

Kind regards

alpibucky