Musical Fidelity B1 doubts

Hi,

I'm restoring an old Musical Fidelity B1 amp. I've found some pics and schematics in the web, but it seems that my model is quite different: apparently it seems to be a very first version, or even a pre-series unit (serial # 00049)

Especially, I have not found any pot able to adjust the bias current (see pictures). Moreover, R40 and R46 resistors have never been mounted. The only adjusting point is a 2K trimmer mounted at R30 place on right channel only , I suppose to allow a preset balance between the two channels.

No way to balance the DC output and to adjust the bias?

Many thanks in advance, Paolo
 

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Thx Huggygood,

I've had a look at that post, unfortunately I have not found any mention about my (pre-series?) model.

In fact, my amp works somehow but with no chance to actually control the DC offset (currently not so big, but not null, 50-100mv with no load applied) and the bias current.

I wonder if it would be possible to modify my circuit in order to allow those adjustments