I've decided to convert my Holland Amp to Master Volume. It's just too damned loud to get it to impart some natural overdrive. Even when playing live, I seldom have to volume up above 4 on the control and it's still pretty clean at that level.
I'm going to use a variation of the Ken Fisher "type 2 MV" that is called the LarMar mod. It involves fitting an additional volume control after the last preamp valve (called the phase inverter).
I order the parts ( a volume pot and 2 resistors) on Tuesday - they were delivered this morning - pretty good considering that they came from the U.S.
Unfortunately I was presented with a demand for import duty / VAT by the courier delivering - hadn't factored on that. It's slightly annoying because the company I ordered from (Digikey) redirects to a U.K version of their site - all priced in pounds. It doesn't make it obvious that the goods will actually be shipped from the states - another similar company (Mouser) operate in a similar way but actually despatch from a European Distribution Centre - cutting out Import Duties.
Still, at least a have the bits - albeit they are far more expensive that I'd bargained on.
I want to be able to lower the output level to the extent that at "4" on the current volume control, I'm getting a bit of amp "crunch". I'm realistic, not expecting the MV to deliver fantastic tones at bedroom levels so we'll see how it goes. I'm going to fit the new Volume control on the reverse of the amp so as not to mess the front panel up.