Hmmm, who'd have thought a 50w marshall would be too loud cranked - rock on,Mine has the original Celestion G12-70 speaker. I play it in a smaller room with low ceilings. I wonder if that has something to do with it. Plus, it gets way too loud when it is cranked. Maybe it just sounds harsh because of the volume.
Does adjusting the bias affect the overall tone and gain of an amp just when it is played at higher volumes or will you notice a change even at lower volumes(preamp dimed)?
An Eminence V12 would help things out considerably-I've used one in my 4210 combo for about 3 years now,and it helped tighten up the low end as well as smoothing out the high end a good bit.Overall,it makes my amp sound like it's running through a closed back 2X12 or 4X12.Try one out if you get the chance.