Mark 2b overhaul/update

[needtoknowbassist]

I just saved a 60watt, EQ, no reverb, 1x12 Mark 2b from going into the dumster. It was blowing fuses. I changed the power tubes and now no more blown fuses. I was looking for a amp project and this fell into my lap. Very intregued by the chance of a fender clean sound and a Marshal rythm sound. I used to gig with a 2x12 Maverick back in the 90's and loved it. Become for a fender guy since, so the Mark 2 sounds like it could be the best of both worlds.

I have a few questions:
1. What should be replaced on a 25 yr old Boogie besides the tubes? Filter Caps?
2. How can I lower the output/ volume?
3. What can I do to make it lighter? I'm looking at the Jensen NEO speakers.
4. Is there a way to get rid of the pop when footswitching?

Thanks

 

[RR]

I have a few questions:
1. What should be replaced on a 25 yr old Boogie besides the tubes? Filter Caps?
2. How can I lower the output/ volume?
3. What can I do to make it lighter? I'm looking at the Jensen NEO speakers.
4. Is there a way to get rid of the pop when footswitching?

Thanks

1 Yes filter caps, you said you changed power tubes so you should be fine and if you are not experience microphonic tubes, your preamp tubes seems fine.

2. Boogies especially Mark I, II are loud and headroom clean, only way I think I could lower the volume is use less efficient speakers.

3. I familiar of NEO magnet speaker technology, but can't make comment on Jensen you mentioned since I personally haven't experienced current line of Jensens.

4. Mark II runs on a relay to change channels, well mine does. I think changing the relay to a different channel system is major work. One solution that may quiet down the pop, is changing the Carling footswitch if the pop is unusual loud.

Yes, I love Mark IIs, as well as vintage tweed, BF, SF Fender. Glad there's some members that like moderate gain and I'm looking for a Maverick too. The LoneStar Special looks pretty cool.

 

[BPski]

I have a few Mark IIB's.
1) I changed all the electrolytic capacitors in the amp. The filter caps are the most important followed by the cathode bypass caps.
2) I have found that using a less efficient speaker will lower the overall volume and punch of the amp. Another thing I do is use the 4 ohm jack with an 8 ohm speaker. The mismatch lowers the output and punch a step further.
3) I have tried the Jensen Neo speaker and it sounds pretty darn good. I liked it much better than the Celestion. I think Eminence has one out now that I have not tried. The Fane AXA12 is a light speaker that handles 100 watts, has an alnico magnet and sounds great.
4) All my Mark IIB's have a pop when you switch channels. When I am not playing the pop is significantly lower than if I switch while playing. I think the later IIB's are more quiet. All mine are early ones. Call Mike B. at Mesa. He may have a solution.

I hope this helps. Have fun!!!!

 

[needtoknowbassist]

There is no hum. Does that mean my all my caps are good? The clean sound sounds great. The distorion is a little flabby sounding. I'm not a high gain guy, 7 on the master, with a either a Telly or a Thinline with Humbuckers.

Sounds like the Jensen might get things heading in the right direction.

Thanks

 

[BPski]

A hum is only one indication of bad filter caps. Mushy bottom end, ghost notes or weird noises along with the notes are indicative as well.

I tweaked my Lead channel to be a little less flabby. The filter caps will help as well. You can try a 5751 in the V3 spot and will clear up the Lead sound. It has less gain than a 12AX7.

The Jensen sounds good. I have one in my 60/100w IIB. It sounds tight in the bottom end and has a nice texture to it. It's not too stiff for a high power speaker. That Fane AXA12 is a really good one too. The Jensen sounds better for clean playing though. The Mesa MC-90 is a good speaker as well and not too heavy.

Have fun!!!!

 

[RR]

.... That Fane AXA12 is a really good one too...

I don't wanna hear more about this Alnico Fane, its killing me :x

Kidding, I love Fanes, I have both a pair of Crescendos and Axion AX12 Ferrite and now eyeing the AX12A Alnico. But the price, :shock: Alnico are warmer but expensive speakers in general.

4. Mark II runs on a relay to change channels, well mine does. I think changing the relay to a different channel system is major work. One solution that may quiet down the pop, is changing the Carling footswitch if the pop is unusual loud.

Mark II (not sure about the Mark IIC) runs off an analog relay where the later Mark Series as well the other model runs off digital control (correct me if I'm mistaken) relay. Installing a digital control relay I would guess is major work. Sometimes the pop comes from the Carling Footswitch going out, (contact not as clean). It then needs to be replace.

 

[RR]

.... That Fane AXA12 is a really good one too...

I don't wanna hear more about this Alnico Fane, its killing me :x

Kidding, I love Fanes, I have both a pair of Crescendos and Axion AX12 Ferrite and now eyeing the AX12A Alnico. But the price, :shock: Alnico are warmer but expensive speakers in general.

4. Mark II runs on a relay to change channels, well mine does. I think changing the relay to a different channel system is major work. One solution that may quiet down the pop, is changing the Carling footswitch if the pop is unusual loud.

Mark II (not sure about the Mark IIC) runs off an analog relay where the later Mark Series as well the other model runs off digital control (correct me if I'm mistaken) relay. Installing a digital control relay I would guess is major work. Sometimes the pop comes from the Carling Footswitch going out, (contact not as clean). It then needs to be replace. Mine is not that annoying, its just a light pop. I did wear out the original Carling footswitch .