Need advice on Mark IIB.....

[BMcNibbnles]

A lot of questions here, so whatever you guys can answer would be great....

I own a 1981 (or, 82, I can't remember) Mark IIB with the following specs: 60/100 watt, reverb and graphic EQ. No simulclass. I have heard good things about sending older amps to Mesa for a good "cleaning." I have a couple of questions:

1. What exactly do they do when you send it to them?
2. How much does it actually affect the TONE? (i.e., how does the tone become better?)
3. How much does it cost? (aside from shipping, which I will have to figure out on my own)
4. What does the "effects loop mod" do and how does it affect the tone?

And, this is one of the most important questions I have....

5. Since the knobs on the IIB pretty much all work together, is it possible to install a knob on the amp that controls ONLY the volume of the CLEAN channel, but allows you to keep the "volume I" knob cranked up so you can get the good high gain setting on the lead channel? If this were possible, you could switch channels and not have to worry about a DRASTIC increase in volume on the clean channel.

Any answers to any of these questions would be greatly appreciated.

 

[av8or3]

Hi, Welcome to the forum. I'll try and help you with some of your questions.
1. They will replace the filter caps along with some of the smaller electrolytics,clean the pots,tighten the sockets and repair/replace any bad components they uncover.They will also test your reverb tank and perform a mod that will allow it to perform better. Call ahead to get a RA# and an estimate on time/$. They will need only the chassis/tubes and the reverb tank. 707-778-6565

2.The amp will open up with more of a dynamic range,become more touch sensitive, have better lows and have smoother and better sustain,especially with single coil pickups. Boogies love humbuckers but it sounds better with single coils after the work is done.

3.The cap job/tune up about $200. The effects loop mod $300.

4.The effects loop mod reconfigures the amp to allow you use all the front panel control knobs in the send signal and adds a third volume knob on the back that allows you to adjust the post level anywhere you like. With nothing in the loop it can be used almost like an atenuator. Set up all your controls to get the tone you like and then turn down the overall output of the amp to suit the room you're playing with very little change in tone, Usually requiring only small tweaks to restore any loses. The third volume knob can also be used to add gain ABOVE what the amp would normally produce.When you get the amp back Mike will have marked the new volume knob with a white dot to indicate where "normal" output is,usually about 8, above that it's all extra (louder) gain.

5.The effects loop mod will help with this. You will find that the two channels will have moved closer to each other as far as levels/output are concerned.

There you go. I had all the above work done to my IIB and can recommend it whole heartedly. Well worth the $.


Good luck,
Jim

 

[BMcNibbnles]

Thank you for that extraordinarily thorough reply!

 

[gonzo]

i had my '81 mark2b locally refurbished/tuned up, by an authorized boogie repair guy.

saved me BIG BUCKS, the shipping alone was more than what i paid for a full cap/clean/electrolytic upgrade.


i decided against the effects loop mod, don't feel like my unit needed anything changed.
the fx loop works great with my Yamaha DG Stomp, which has both input and output control, so i can dial the fx loop into unity gain very easily, sounds great.

i don't record with the FX loop, so when it really counts to me, it's not even an issue.

just another idea if money's tight, like it is/was with me.