Mark IIB that I don't understand and need some love! help.

[Danne]

Hello. I know I'm new, it's just that now I have a Mark IIB (EQ/ 100-60 switch-reverb) and I need some advice / protips.

I love the way this amp sounds. CLEANS shine and distortions are not crunchy, but RAW, articulated and in ur face powerfull (Lead gain at 9, lead volume at 9... V shaped EQ... drooools)

Mesa changed all the caps and fixed other stuff, added a new reverb tank (a $400 service) restoring this amp to like new conditions.

However:
(1) There is a significant VOLUME drop in the fx loop and no mix/blend in the fx loop make this amp unusuable for flangers, phasers and delays. How can I wah really good if this fx loop is like this? Is this normal in these Mark IIBs? Even if it is, or isnt normal, how can I mod so I can have a REAL FX loop. This bothers me. I love pedalboards and, since I AM NOT using a distortion overdrive (i just love the mesa dist so much) I need to modulate the original mesa dist via fx loop, which to my surprised, sucked. And I am not happy with this.

(2) Even tho reverb tnk is new, reverb is not functional. SUCKS too, because I would love to try some sort of surf licks, which i dont know if they can be delivered, because the reverb is non functional. There is some kind of ground cable in the tube socket part of the reverb, and the springs are slightly noticeable thru teh speakers when u move them manually, but the reverb knob don't work.

(3) SOMETIMES I listen to the footswitch pop, sometimes i dont. How can i fix this? Changing the switch in the pedal? Or is it in the amp?

(4) Yes, a silly question I will ask. How can I mod/change this amp into the sought after Mark IIc+ with all the wonderful pluses. Is it even possible? The shared EQ/settings are kind of a pain in the ***, but usuable.

(5) In terms of functionality, not soundwise or subjective stuff, how does the IIB compare to the IIC or IIC+?

I found some schems and I have a friend that can service this amp. And I have the receipt from MESA that they serviced this amp. But I should know if this **** is normal or what. So... yea, you should know by know what to do.

Sry for the long post and TNX for any replies. Ill be sure to keep u guys posted. This amp (s/n 8,6xx) kick ***

 

[>Photi G<]

Well, first, let me tell you that it is now impossible to upgrade a B to a C+. The differences are in favor of the C+, with a REAL FX loop, great reverb, quiet footswitching, and of course, more gain. You can have the FX loop modded so that it responds better. The B had the first FX loop ever on a guitar amp, so there were bound to be problems with it. The reverb definitely has a problem, and should be checked out, and if the footswitch is popping, the LDR's could be bad, or this could be an early B with relays for switching.

And a kind word of advice, Stay away from schematics! They're all wrong! Mesa has a history of cutting corners with their schematics. For example, the IIB's schem is just a modified version of the IIA's. None of the upgrades were added, just the FX loop in the spot that was most convenient for their technician/draftsman at the time. Also, the IIC+/III's schems are just modified copies of the IIC schematic, with some added components. They are really innacurate, so I wouldn't trust'em.

 

[Danne]

Tnx for ur reply.

So I am assuming that my FX loop "problem" is normal, the volume drop thing? I love the clean channel of the MkIIB, is the C or C+ channel the same? How's the reverb in the MkIIB?
(Whats an LDR?)

 

[av8or3]

Mike Bendinelli @ Mesa can do the FX Loop mod for about $300. This will make the the Loop usable and add another volume knob to the back that can be used almost like an attenuator, or alternately to add gain. It's pretty cool, I had it done to my amp and I feel it was worth the money.

Also, the reverb fix could be as simple as being plugged in wrong, try reversing the leads where they go into the amp.
Good luck with your new amp
Jim

 

[gonzo]

i have a 1981 mesa mark 2B cream head, 60 watt, GEQ, no reverb, original owner. i used it for 4 years of fulltime road work, and have used it for gigs and recording ever since.
i post tunes in the song forum all the time, if you want to hear it in action.



#1- i've never experienced any kind of level drop in my FX loop, not using stomp boxes, or rack gear. something must be wrong with that loop.

#2- usually these types of fixes are not expensive. take it to a registered mesa repair guy.

#3- my switch always had a little pop with it. i learned to time channel switching with covering the sound up with either my delay kicking in as a result of the change, or a snare hit, or something that is in time musical. no one EVER commented on the pop sound, not live or in the studio.

#4- simple answer, no.

#5- i've played the IIc, and the C+, and i prefer my IIb. it's purely subjective.

 

[BMcNibbnles]

Although most of your questions have already been answered, allow me to give my thoughts as well:

1. I had a Mark IIB combo and my effects loop SUCKED. I don't remember a volume drop, but I remember thinking that the quality of the effect wasn't very good and it should have been. For example, I have a T.C. Electronic Nova Delay pedal that literally sounded better in the effects loop of a $300 Peavey solid state amp. Through the Mark IIB, it sounded muffled and actually kind of distorted. I read somewhere that the IIB was known to have problems with its loop. There IS an effects loop mod that fixes the problem, though. Just call Mesa, they'll tell you about it, apparently.

2. My reverb was awesome on this amp, so I don't know what to tell you here.

3. The popping sound was annoying as hell. I hated it. Like the effects loop problem, the popping between channels was a widely known issue. I never had to worry about it because I only used the amp's lead channel because, if you want a really great lead tone, the clean channel is unuseable. But, the few times that I did change channels (even accidentally), it was extraordinarily frustrating. Not sure WHY it happens, just letting you know that it's a known issue.

4. You can't mod a IIB to a IIC+. I think it was possible a while back, but there are some components that aren't in production anymore and, without those components, it's impossible for Mesa to upgrade the IIB to a IIC+.

If you want a IIC+, but can't afford it - I highly suggest getting a Mark III, which is what I did. I got sick of not having a two channel amp, not having a good effects loop and not having enough gain, so I got myself a Mark III. It was the best decision I could have made. The III pretty much sounds like a IIC+, but more aggressive and with more gain. In other words, it's A LOT closer to a IIC+ than a IIB is. The IIB is an amazing amp, but it's not for everyone.

5. The IIB doesn't compare to the IIC+ at all in terms of functionality (at least for me). Like I said, I could never get a great lead tone AND clean tone at the same time because you have to CRANK the clean channel's volume, which for some stupid reason, affects the lead channel. In my opinion, it was a really stupid design. The IIB could have been a phenominal amp, but for that very reason alone, the amp irritates me. Two great, fantastic tones at your fingertips, yet you can only have one at a time - especially when the fix would have been easy - PUT ANOTHER KNOB FOR THE CLEAN CHANNEL! How difficult would that have been?

That's my biggest problem with the "functionality" of the IIB compared to the IIC+.

 

[>Photi G<]

Tnx for ur reply.

So I am assuming that my FX loop "problem" is normal, the volume drop thing? I love the clean channel of the MkIIB, is the C or C+ channel the same? How's the reverb in the MkIIB?
(Whats an LDR?)

Yes, the effects loop problem is normal. Keep in mind that the IIB was ANYBODY's, not just Mesa's, first attempt at an effects loop. Like most electronics, failure, or poor functionality is usually discovered while the product is in use, and as the problems surfaced, they were rectified, until the FX loop was refined in the IIC/+.

I can't speak for comparison purpouses, as I've never owned or played either the B, C, or C+. I had the chance to own a B once, but I passed it up, stupidly.

An LDR, or Infrared Optocoupler, is a solid-state switching device that is used as a substitute for mechanical switching devices, such as relays. It consists of an infrared LED, and a photoresistor, or Light Dependent Resistor. When the LED is lit, the photoresistor allows current to pass through it. The IIA used relays for channel switching, but they were found to make popping sounds when switched, so in the IIB, LDR's were used instead, to quiet it down.

 

[gonzo]

well, i just don't get it.

seems a lot of folks have issues with their 2b effects loop....

and i never have.

sounds exactly the same when i yank everything out of the loop, as when i have my yamaha DG stomp plugged into the loop, but sitting on idle.

that unit, has an input trim and output trim, i always just match it to unity gain, and it sounds perfectly fine.


i wonder if there is something odd, unusual, unique or tweaked in mine?
i bought it directly from boogie, brand new, and MB has his initials on it.......?

i've never had any problem matching my volumes between clean channel and lead channel...

granted, you have to compromise the gain settings, but for me it's not an issue-
i find the clean gain i like best, at volume, then i tweak the lead drive and volume to give me the crunch i want, and use pedals to drive it harder for solos.

but you're right, if you want to dime the lead, and have the clean sound good, you can't, because they share controls.
it just really depends on how you use it.

i can gig with it just fine, but i mostly use it for recording these days, and i always twist the knobs from scratch at every session anyways......

 

[Danne]

tnx everyone for ur wonderful replies. In a couple of minutes I am going to upload pictures of MkII and the fix and problems and other stuff. Keep posted.

 

[Danne]

 

[Danne]

First of all:

(1) Tnx; the reverb somehow was wired wrong, so we just had to put the switch the cables. Love this reverb, A LOT. Even tho I prefer the twangy surfy Fenderish thingfor surf rock, obviously.

(2) Secondly: What the X means? I know it is Export, some kind of transformer, but why would it be so important that it gets written in the chasis anyways? This amp was made the same year I was born. I love it.

(3) About dist and clean: To me, distortion is a bit tricky to get, but there is no way I can get a bad clean tone with this. every clean just sounds blissfully right. I'm using a telecaster with an EMG81/EMG60 active pups. The EMG60 takes care of the cleans, of course

(4) This amp was restored: the previous owner bought this amp in non working condition, send it back to mesa and they made a huge work putting new tubes, and caps to the amps (you can notice, the caps are as new) I dont know a lot about whats new and not, but please rate the pictures and conditions. It was a $400 work and I would like to know ur opinion if it was worth it.

(5)FX Loop. We actually found out that there is NO VOLUME DROP inmy fx loop. My crappy phaser have a volume drop that I never really noticed via input but it was lot more obvious in the fx loop. HOWEVER, fx loop sounds really crappy, delay didn't went thru really well. The fx loop is unusable.

I just dont want to have a overdrive in my pedalboard since i fuckin love this distortion. It's legendary and unique, believe me. So, I wantedto use my effects via the fx loop. My friend, who is a lead guitar (I dont solo, just rythm) told me that it was about time I used some good overdrive to crank the original dist and with that I would be able also to use via input my modulation.

How can I make my amp's distortion come reallly modulated with fxs? would the OD thingy work? Also, He is recommending me a BB Pre amp (I know dists I use in clean channels, i dont know anything about tube screamers and let alone anything about a overdrive over my original distortion). What ODs would you guys recommend for this amp? I think is more feasible spending a couple of bucks in a OD/Dist so i can use my pedal in the input, than spending me 300 to fix the loop.... which gets e to another point

(6) Does anyone knows how to do the FX loop mod, DIY?

(7) Setting of other MkIIBs would be appreciated, specially if someone is using EMGs. Does anyone here have posted settings of some sort so I can try them out?

(8) There is a 5th preamp tube near the power tubes (refer to pics) whats the purpose of that tube? another 12ax7 thats being used as power amp and just placed there? Oh, and pleas enotice in the pictures where you can see the date of the amps, in the middle there is about 4 inputs (2 of those are for the reverbs) but I wonder why Mesa put other inputs there? What are those for?



SORRY for so many questions. I'm just fascinated with the amp and by how knowledgeable you guys are. Peace.

 

[BMcNibbnles]

Yeah, like I said, the effects loop really sucks on the IIB. I know Gonzo apparently doesn't have any problems with his and, from what I've heard, he gets an INCREDIBLE tone from his Mark IIB.... but, I'd like to make the point that a lot of that is in the fingers, too. [that's a compliment, by the way, Gonzo, not a dig on your opinion toward the amp]

What you mentioned about the delay not sounding right is exactly what I experienced. It sounded distorted and unpleasant. Something was definitely wrong with the design of the Mark IIB's effects loop - or, the components they used. Either way, it sucked - for me. (and, Danne)

Danne, I'm not exactly sure what you're asking about your distortion. You asked: "how can I make my amp's distortion come really modulated with effects?" What do you mean by that? You mean modulated as in a CHORUSED effect? If that's what you're asking, you're doing the right thing by using the loop. Unlike delay, chorus CAN work if you try putting it in front of the amp (rather than the loop), so if the loop sucks, then try putting the chorus pedal in front of the amp. I don't like delay in front of the amp with a distorted tone, though, but that's just me.

I have a feeling that you're probably not going to be satisfied with your effects on the IIB unless you get the effects loop mod, which apparently makes the loop on the IIB much more useable.

Concerning OD pedals for the IIB, here's my personal take on that:

The IIB is very dark sounding (at least that's how I set it up). I always had the presence all the way down because it was way too fizzy for me - even on really low settings. I had bought a Fulltone OCD pedal before I fully realized how dark the IIB was and the problem is that the OCD is ALSO very dark sounding. So, my advice is.... do NOT get an OCD pedal for the IIB.

The BB Preamp, on the other hand (which you mentioned) is more on the bright/ trebly side (in a good way) and I personally think it would make a good match for the IIB. A friend of mine has a Mark V and it sounds AMAZING with that amp. I think it'd sound awesome with a IIB.

By the way - don't put your distortion/ overdrive pedals in the loop. Make sure you have those pedals going into the front of the amp, as well as your wah pedal. You really only want time-based effects going in the loop (chorus, delay, etc.). Some people say volume pedals and boost-type pedals are good in the loop, though, but I don't know. I have never tried those things in the loop.

To answer another one of your questions - whether you should spend money on a pedal or to fix the effects loop - what happened to me was, I didn't think the IIB had enough gain, so I tried to "give" it more gain by buying the OCD. The OCD gave it more gain, but it just never felt completely natural. It always felt a little fake. I then began to realize that I was trying to make the IIB something that it's not.

So, my advice to you is this: if you KNOW that you 100% are in love with the amp and that you're going to be keeping it, I'd get the effects loop mod. I personally can't live with crappy sounding effects and, if you have good pedals or other equipment, it sucks to have their tones compromised. I contemplated sending my IIB in for the effects loop mod, but decided against it because a) I knew I needed a different type of distortion for the lead channel, anyway and b) I could get a Mark III that had a better distortion AND a better effects loop, so I decided against modding the IIB. There was just no point to doing it. But, if you are really digging the amp otherwise, then it's totally worth it.

 

[Danne]

Yeah. I was kinda figuring that out. Mi flanger and phaser just don swoosh the distortion enough in the input, and well, the fx loops is failing too. Other effects via the input (delay, dists) works fine. Fx loops was to modulate distortions with fx like, lets say, a wah or a flanger. Those always sound crappy in the input. they should be in an fx loop.


I am considering the mark III or mark IIC+ thing, but I dont know where to look or if someone is just willing to trade or where to find one at a great price, same way i found this.

Yeah, like I said, the effects loop really sucks on the IIB. I know Gonzo apparently doesn't have any problems with his and, from what I've heard, he gets an INCREDIBLE tone from his Mark IIB.... but, I'd like to make the point that a lot of that is in the fingers, too. [that's a compliment, by the way, Gonzo, not a dig on your opinion toward the amp]

What you mentioned about the delay not sounding right is exactly what I experienced. It sounded distorted and unpleasant. Something was definitely wrong with the design of the Mark IIB's effects loop - or, the components they used. Either way, it sucked - for me. (and, Danne)

Danne, I'm not exactly sure what you're asking about your distortion. You asked: "how can I make my amp's distortion come really modulated with effects?" What do you mean by that? You mean modulated as in a CHORUSED effect? If that's what you're asking, you're doing the right thing by using the loop. Unlike delay, chorus CAN work if you try putting it in front of the amp (rather than the loop), so if the loop sucks, then try putting the chorus pedal in front of the amp. I don't like delay in front of the amp with a distorted tone, though, but that's just me.

I have a feeling that you're probably not going to be satisfied with your effects on the IIB unless you get the effects loop mod, which apparently makes the loop on the IIB much more useable.

Concerning OD pedals for the IIB, here's my personal take on that:

The IIB is very dark sounding (at least that's how I set it up). I always had the presence all the way down because it was way too fizzy for me - even on really low settings. I had bought a Fulltone OCD pedal before I fully realized how dark the IIB was and the problem is that the OCD is ALSO very dark sounding. So, my advice is.... do NOT get an OCD pedal for the IIB.

The BB Preamp, on the other hand (which you mentioned) is more on the bright/ trebly side (in a good way) and I personally think it would make a good match for the IIB. A friend of mine has a Mark V and it sounds AMAZING with that amp. I think it'd sound awesome with a IIB.

By the way - don't put your distortion/ overdrive pedals in the loop. Make sure you have those pedals going into the front of the amp, as well as your wah pedal. You really only want time-based effects going in the loop (chorus, delay, etc.). Some people say volume pedals and boost-type pedals are good in the loop, though, but I don't know. I have never tried those things in the loop.

To answer another one of your questions - whether you should spend money on a pedal or to fix the effects loop - what happened to me was, I didn't think the IIB had enough gain, so I tried to "give" it more gain by buying the OCD. The OCD gave it more gain, but it just never felt completely natural. It always felt a little fake. I then began to realize that I was trying to make the IIB something that it's not.

So, my advice to you is this: if you KNOW that you 100% are in love with the amp and that you're going to be keeping it, I'd get the effects loop mod. I personally can't live with crappy sounding effects and, if you have good pedals or other equipment, it sucks to have their tones compromised. I contemplated sending my IIB in for the effects loop mod, but decided against it because a) I knew I needed a different type of distortion for the lead channel, anyway and b) I could get a Mark III that had a better distortion AND a better effects loop, so I decided against modding the IIB. There was just no point to doing it. But, if you are really digging the amp otherwise, then it's totally worth it.

 

[BMcNibbnles]

Yeah, there's no right way to do it. I don't like having delay in front of the amp at all (with distortion - clean is okay), but I'll try the wah in the loop. That's actually one thing I haven't tried.

As for the Mark III/ IIC+, keep in mind that you'll pay an arm and a leg for a IIC+. If you can afford one (somewhere between $1,500 and $3,000+, depending on the features), your best bet is actually ebay, or even this forum. I'm sure you could find someone who is willing to sell you a IIC+ here. I couldn't afford even close to what a IIC+ costs, so I chose the III and I love it. It doesn't hurt that I got a red stripe, which some say is the closest one to a IIC+. Not sure how true that is.

Oh, and there's also Cragslist, if you're in the U.S. Just make sure you try it out, inspect it, etc, before you throw down money. Maybe even check the serial number with Mesa....

 

[Danne]

Yeah, there's no right way to do it. I don't like having delay in front of the amp at all (with distortion - clean is okay), but I'll try the wah in the loop. That's actually one thing I haven't tried.

As for the Mark III/ IIC+, keep in mind that you'll pay an arm and a leg for a IIC+. If you can afford one (somewhere between $1,500 and $3,000+, depending on the features), your best bet is actually ebay, or even this forum. I'm sure you could find someone who is willing to sell you a IIC+ here. I couldn't afford even close to what a IIC+ costs, so I chose the III and I love it. It doesn't hurt that I got a red stripe, which some say is the closest one to a IIC+. Not sure how true that is.

Oh, and there's also Cragslist, if you're in the U.S. Just make sure you try it out, inspect it, etc, before you throw down money. Maybe even check the serial number with Mesa....

cool. im interested in a mkiii, to try it or listening it out. clips? also, whats the value/cost on those? they look an awful lot like the mkii

 

[BMcNibbnles]

Just go on You Tube and find some clips. There are tons of clips. I've seen them as low as $500, but as high as $1,500 (hasn't seen them higher than that, myself). It all depends on the seller and the particular amp.

 

[Danne]

cool. The clips I listened sounded kinda like my Mark IIB. Does someone know what the inputs in the chassis are for in the mark IIB?

 

[>Photi G<]

There are 4 inputs at the bottom of the IIB. The 2 RCA jacks are for the reverb, as you've figured out by now. One of the 1/4" jacks (can't remember which) is the junction between the Pre/Power amp, so you can either take the raw preamp sound out of here and feed it to a power amp, or insert the signal from another preamp and use the IIB as a power amp. The other jack is the EQ/Reverb footswitch jack. On some models, it actually controls the EQ/Gain Boost functions. You'll find out when you try it. Any 2 button footswitch with a stereo cable will work.

BTW, nice pics. That amp has been used and abused! You asked about the HRGX on the side of the chassis. H= Hundred Watt power amp, R= reverb, G= graphic EQ, X= export model. Export model means that your IIB is equipped with an export Power Transformer (Model X101). Possibly the best option you could get to improve your tone on any Mark II. The X101 PT allows you to switch the input voltage taps via a selector switch on the back panel of the amp. So, If you live in the US, you would choose 117V. If you lived in Europe, you'd choose 220V, or 240V, depending on your region. Either the original owner of this amp lived outside the US/Canada, or they planned on traveling often.

 

[Danne]

Tnx for ur rply. That's a really bad place to put a footswitch jack, specially since the channel selector footswitch is in the front of the amp. it would be nice if it were for the reverb. I'll mess with that as soon as I got the time.