I don't really remember this thread but I will chime in here
As far as the resistors go? it's really pretty simple IMO here is a general consensus among experienced builders myself and others notice.
If you want the amp to take on a more aggressive stance go with the MF's in the signal path since they can be (depending on the resistor type) a bit brighter more articulate and for lack of a better word "in your face". The feel is generally tighter as well
.CF's go the opposite direction can color the sound somewhat again depending on the resistor type. These tend to be a bit smoother sounding less aggressive less focused and adds a bit of 2nd order when in OD, so it's a matter of taste and style of music you play. The BM is already designed to be more of an aggressive sounding amp for Rock and Blues (hence the name Bluesmaster) The BM can be at times bit bass heavy with a looser feel mainly due to the hotter (Marshall style) PI design 50K mid pot and .022 mid-cap and lower slope resistor less GNFB no NFB V1 etc.etc.As far as the Mustards go?.Go for it.I've used these in ODS amps with good results!
The problem IMO with going to a cathode biased OPT section is when in OD and the amp cranked you may have a problem with the low end being too loose and muddy sounding and at high vol levels may experience some blocking distortion...I wouldn't go any higher than 5uF on the cathodes and for higher volume use, add a fixed bias/cathode biased switch on it.But that is just me
Again! these are subtle changes..Some people notice it? others not so much.It all depends on your frame of reference, what amp you are comparing it too and other factors(guitar/speakers/cabinet type/tubes, and how you run the thing)
The Bluesmaster is IMO Dumbles response to the popularity and those wanting something more JCM 800-ish which was a wildly popular amp in the 80's
.If you really study the design "the BM is a combination of both the JTM 45 (on clean channel)and JCM 800 (Overdrive channel boost on)"
Tony
