Mark IIb upgrades?

[Z2B]

Hi,

I've had a Mark IIb 60w black head/cabinet w/ EVM EQ & verb for about 30yrs.. fairly recently added a vertical 2x 12 Boogie cabinet to it as well. Still a great sounding amp. I'm wondering what kind of upgrades could be done to it. I read that I can't upgrade it to a C+ due to a circuit board that isn't available anymore, not that I want to per say but was considering that after all the hype on the C+. If a board could be found, what else would be involved in the conversion?
What's are the improvements in the c+ over the b? I'll start reading the C+ sticky.. but my question is specific b to c+.

Mainly I want to improve upon the channel switching popping, which it's always had. Has anyone fixed theirs, if so what exactly do I need to do? Pops with the footswitch and by pulling out the knob.

Also if you pull out the main volume boost/gain knob it pops too, how to fix this?

Would the amp benefit from doing a full cap job on it? Are their kits available for this? Any other components that should be upgraded/replaced due to it's age?
What to check for etc.. to determine this?

Biasing.. I understand that this is a fixed bias design, however again due to it's age the biasing circuit could have gone out of tolerance, so has anyone modded theirs to a variable bias for a more precise adjustment? What should the biasing voltage read?

Finally tubes, has anyone used EL84s or other power tubes etc.. in theirs? Aside from socket adapters, what mods if any would need to be done? (Always wondered how they would sound) Going to re-tube it as well.. seems people are liking the Electro-Harmonix tubes as of late..

I can do basic electronics repairs/mods.

Great board here! Need to get the Boogie ready for prime time again..

Perhaps common knowledge here but I Just learned that the name MESA Boogie came from Randall Smith working as a Mercedes-Benz mechanic and Carlos's statement when playing thru an early prototype.. "that thing really boogies".. after 30yrs I just discovered that lol

http://www.ultimatesantana.com/Mesa-Boogie-Amps.html

Thanks

 

[zodiac272]

Welcome! you might like the FX loop mod to your IIB. I don't know anything about mods, or how to perform them. maybe someone else can help. But Mike B. (who probably built your amp) is still working at mesa. he can get your amp to brand new working order. If you google search mark IIB FX loop mod, you might find more info about that. best of luck with it

scott

 

[Z2B]

Thanks for the Info..

Goggled it and got several hits..

I'll make a call out to Mike and see if they are still doing he mod, although if it changes the tone I'm not sure about that.. tone is incredible as is.. always has been. Although I do prefer smooth gain sound over brittle and harsh so if it ups the ante on that even more I may go for it.. The clean tone is incredible, and rivals or bests any modern amp out today.. so glad I've held on to it. Until now I didn't know any better on the FX loop issue, I noticed years ago that when using the effects loop with my outboard reverb unit that is was noisier when using the lead channel so I started using overdrive distortion stomp boxes instead. But to go back to getting that smooth creamy boogie distortion and using todays modern muti fx units via the loop that would be the best of both worlds to say the least.. but, how much different will gain channel sound if I go with the mod.. and could it be reversible if I don't like it... 8) Decisions decisions...

I need to hear some quality examples of the C+ sound to see if I like that over my B sound which I've always loved..

Can anyone direct me to some links showcasing the C+ sound in a variety of styles?

Thanks again

Welcome! you might like the FX loop mod to your IIB. I don't know anything about mods, or how to perform them. maybe someone else can help. But Mike B. (who probably built your amp) is still working at mesa. he can get your amp to brand new working order. If you google search mark IIB FX loop mod, you might find more info about that. best of luck with it

scott