Studio Caliber 22+ Tubes

Ive had this since '86 as a practice amp. Its begining to have more hiss. I think it may be time to retube the whole amp (5) 12ax7's and 2 EL84. I think...can anyone give suggestions on which tubes I should replace with? Thanks

86??? Its a miracle it still works at all. I guess there's the proof that older tubes are far superior to the new production. If you want it to last another 20 years and dont mind spending a small fortune, NOS is the way to go.

(TimbreWolf please chime in here...he seems to be our resident expert on NOS glass, and certainly better equipped to help you if you decide to go this route)

For new-production tubes, I would recommend JJ's as they are reliable, sound great, and are dirt-cheap. Dont expect them to last 20 years though.

www.eurotubes.com (JJ's only)
www.dougstubes.com (other brands, competitive prices)
www.kcanostubes.com (a variety of NOS and new-production)

(TimbreWolf please chime in here...he seems to be our resident expert on NOS glass, and certainly better equipped to help you if you decide to go this route)

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Uh oh, what have I become?:roll: Well, thanks NGNC! I'm not sure I could say more than I've already said in that Triaxis thread ( http://www.grailtone.com/forum/viewtopic.php?t=749 ), and I'm not directly familiar with the Studio Caliber 22 (LilSteve, check out the manual to find out which tube does what). Besides, we each have our own tastes. I'm just trying to urge you guys to experiment some...

Please, any of you, write up your impressions if you start delving into the deep end of tube madness.

I guess I haven't expounded on my EL84 experiments yet. In a nutshell, I favor Tungsram EL84 for my 20/20, but would recommend Mullard, Sylvania (black plate), Amperex, RCA (black plate), and Tesla (original, emphatically not JJ), and Matsushita, roughly in that order of preference. This all depends on matching tubes to the fixed-bias of the amp. I know it's more interesting to find out exactly why one prefers one tube type over another, but I don't have the time today. Caveat: some amps respond well to power tubes that sound terrible in others, and vice-versa, so much depends on the circuit, and how you use the amp.

So looking at the back of the amp V1/V2 are lead mode and V3/V4 are rhythm and V5 is reverb, right? (help me here) So I need two matched sets? Correct?

Could I replace V1 with a 12au7 to control the gain and mellow out the amp?

While were at it, what about a replacement speaker?

LilSteve -

Is it the Studio Caliber (6 12AX7s), or the Studio 22+ (4 12AX7s)?
I'm not directly familiar with either, but you can download the manuals (available to download from M/B http://www.mesaboogie.com/manuals/user_manuals.htm ) and see what they say. Or contact Mesa if the manual is too vague.

I do know that you do not have to buy "matched sets" of preamp tubes ("matched set" concerns only apply to power tube pairs or quads).

As for speakers, I'm a fan of Ted Weber's designs ( http://www.tedweber.com ), but I have not tried a lot of other aftermarket options other than these. Ted is always very helpful, and you can contact him directly by email to ask his help, just make sure to describe how you'd like to improve your sound. All my Weber speakers have been an improvement (stereo rig: 12" Alnico Silver Bell and Blue Dog combo; 12F150 in another combo amp). What do you have, and how would you like to improve it?

By the way, I'm supposed to receive an email notification when a reply is posted, and I have not been getting these. I'll have to check if that feature is malfunctioning.

Studio 22+

4 12AX7 + 1 12AX7 (for reverb) =5 total

I spoke with chris at Boogie and DL'd the manual. Im not hi-gain player, would replacing a 12au7 in V1 smooth out the amp?

Wow, that manual is not very useful - it only identifies four 12AX7s. It's a little difficult to answer your question with the detail I'd like, since I can't trust the manual. According to the manual, V1 is for the lead mode only, and it seems that V2 is the main input/rhythm mode. I would suggest substituting at V2 (second from the right) first, and see how it effects your sound. I've found I like having the lower-gain tube earliest in the circuit. But try V1 too, and see what that does (it doesn't hurt to experiment).

I would not recommend a 12AU7 because the gain drop is so extreme (down to about 20% of a 12AX7). Many people prefer a 5751 (70% gain) for this purpose, especially when they hear that this is a trick that Stevie Ray Vaughan may have done. But I found I prefer a 12AT7 (60% gain) - specifically, the Mullard 12AT7WA/CV4024 ('70s or '80s production), which has "smooth" written all over it.

Let us know your results.

Ok so I swapped out V1 through V4 with EH 12AX7. They really took the hiss out and quieted the amp down some. I havent found a 12AT7 to replace in V5. Also swapped the EL84 to Groove tubes (hey they were cheapo @$19 bucks)

It brought back a little more gain. On the rhythm channel (clean) there is a little more breakup. Might swap 84 again to NOS (dont know what yet) Sounded good for blues/rock cleaner tones, but looking at keeping this as my clean amp.

Don't have a studio .22+, but I have a .50cal+, which is the same front end with 6L6 power amp.

What happens with V1, according to the schematic published in the Tube Amp Book, is that the first section of V1 is on all the time, and the second section of V1, along with some other circuitry, gets turned on in lead mode. It really isn't a 2 channel amp, but it's really a switchable extra gain stage.

The answer to your question about 12AY7 is yes, it will reduce the gain of the amp. I have done it myself. I got a NOS RCA for $12 with shipping on EvilBay. It does clean up the rythym "channel" fairly nicely. Anyway, it's a cheap experiment. AFAIK, any 12**7 tube will substitute for another.