New Boogie day: rackmount Mark III blue stripe

[Whoopysnorp]

Though I've been running a rack setup with a Studio Preamp and a Simul 395 for a long time, this is my first 'official' Mark series purchase. I just got back from giving it a little volume down at the rehearsal space. Basically it's replacing the Simul 395 so I can stop carrying two output transformers and sets of tubes around with me in my rack when I only ever use one. Right now I'm just patching the Studio Pre into the effects return, but soon I plan to rig up a switching system where I can switch between the Studio Pre or the effects send of the III. That way I've got instant access to four useful channels, and five if I do the R2 mod! The Studio Pre has the best cleans, so I'll probably keep using it for that, plus it has a smoother lead tone than the III. With the III I can have maybe a pushed clean, whatever I get happening on R2, and of course the high-gain tone of death on the lead mode. That rack is looking pretty intimidating right now with two separate graphic EQs and all the knobs.

I did have one question--the amp came with a quartet of Mesa STR440s but I put a set of Svetlana EL34s that came out of a Marshall I used to have in the outer sockets. I think I'm liking the tone a little better that way, but I don't know what kind of current they're drawing (my bias probe is broken at the moment). Is it as critical with the class A pair to have them in Mesa's bias range as it is with the A/B pair?

 

[robredo_mattila]

sounds cool! I've been thinking about rackmounting my Purple stripe instead of getting a flightcase.

Got any pictures?

 

[camsna]

The class A pair is cathode-bias. Should be fine

 

[Whoopysnorp]

I'll take pictures next time I'm down there.

 

[Whoopysnorp]

Finally took some photos of this monstrosity. I swapped out my Roadready 4x12 for this 2x12 (it's a Lopo cab with a V30 and a G12T-75) because the volume level isn't so out of control. This rig is now definitely complicated enough that I'd probably have to give a crash course to any other guitarist who wanted to try it out!

 

[trem]

The class A pair is cathode-bias. Should be fine

No, it's not cathode bias. It's fixed bias, same with the inner sockets, but hotter. You can't put just any tube, it should still be within Mesa's bias range. In a straight 6L6 setting, put a hotter pair in the inner. But since in EL34 setting it runs pretty cold, go with the hottest pair you can get on the outer (white on Mesa's range).

 

[ned]

Very cool. Can you share some clips?

 

[Whoopysnorp]

The class A pair is cathode-bias. Should be fine

No, it's not cathode bias. It's fixed bias, same with the inner sockets, but hotter. You can't put just any tube, it should still be within Mesa's bias range. In a straight 6L6 setting, put a hotter pair in the inner. But since in EL34 setting it runs pretty cold, go with the hottest pair you can get on the outer (white on Mesa's range).

If the EL34 pair I happen to have running is on the colder side, that shouldn't pose any danger to the amp, right? It sure sounds good to my ears.

Very cool. Can you share some clips?

I haven't any handy at the moment, but I'll make some soon.

 

[trem]

If the EL34 pair I happen to have running is on the colder side, that shouldn't pose any danger to the amp, right? It sure sounds good to my ears.

How cold is cold. At least take it to a tech to get the current draw probed. Clips would be awesome. We need more caliber clips.

 

[Whoopysnorp]

You know what, I was going to measure the current draw when I put them in, when I found out that my bias probe is busted (just the switch to change between measuring plate voltage and cathode current--easy fix but I'm waiting for parts). When I get that fixed, I'll measure it and make some clippage. It sounds awesome, by the way. There are a few additional things I want to do to make all the modes of the III usable at any given time, such as do the R2 mod and get an attenuator after the effects send so it doesn't clip my pedals, but at the moment I have it set up so I can switch to the Mark III lead on the fly. R2 is almost at the right level to match with the other stuff, but it's a hair on the loud side. R1 is too hot to use currently, but the clean on the Studio Pre sounds nicer anyway.

 

[Whoopysnorp]

Bumping for a clip: www.genitalhercules.com/~mcrowe/Mesa.mp3

First section is Studio Pre rhythm, set for a nice clean. Next I switch to R2 on the III, which I actually wish I could get a little cleaner and use as more of a pushed clean, but this will do. Next I switch to lead mode on the Studio Pre, which is my basic crunch and lead tone. Finally I switch to lead on the III, which is set for a very high-gain sound. You can tell when that comes in when the sound gets hairier and more middy. At the very end I switch back to the Studio's lead to demonstrate the difference. I recorded this in Simul with 6L6s in all sockets using an Epiphone SG copy with GTS pickups. Speaker cab is a Lopo 2x12 with a V30/G12T75 combo. I had an MXL V69 on the V30 and a Sennheiser e609 on the T75.