Original Manuf. of Mesa SP12AX7s from Mid-90s?

[scott from _actual time_]

i'm trying to reduce the sizzly high-end on the high gain channels in my Mark V. i like thick high-gain sounds, but the stock JJ preamp tubes were too bright for me.

i've put a Tung Sol reissue in V1. i've tried several tubes in V3: JJ 83S (too bright, probably since it's the same tube as the stock ones), Penta Labs Chinese version of the 9th gen Shuguang 12AX7 (not quite enough gain), unlabeled Chinese tube from 10 years ago (nicely thick but a bit sizzly in the high-end), Sovtek 12AX7 WXT+ (also thick but sizzly).

i've heard of good results in V1 and V3 with Mesa SP12AX7s from the mid-90s. does anyone know what tube brand/manufacturer Mesa used for the SP12AX7s 15 years ago? any chance it's the same brand they're using for these tubes nowadays? (these tubes are the ones with the gray shrink-wrap tubing on them).

i know Mesa's regular preamp tubes these days are JJs. is the SP12AX7s a different original brand, or is it just a JJ selected for lower microphonics?

or (last question, i swear ), does anyone have a recommendation for a different tube to try in V3. it's the 3rd Gain Stage for Ch1/Ch3, 4th Gain Stage for Ch2. should i try a Tung Sol reissue there too, or the Electro-Harmonix 12AX7? or would a long plate tube be a better one to try, like maybe the JJ 803S or the New Sensor Mullard reissue?

thanks very much for any suggestions.

 

[Old BF Shred]

WOW! :shock: :shock:
Wish I could help you. You may be searching for quite a while....
You see, the JJ's are what us Stiletto owners often use to tame brightness.
So if they are too bright, nothing currently made is likely to help.

Maybe certain NOS (ie JAN Philips) or those SPax7's........

Otherwise, I can't help but wonder if you have a technical problem in that amp(?)
Where are you running the "presence" control?
Most Mesa's I've played go a long way with presence kept very low.....(9 o'clock or less)

I sincerely wish you.....
Good luck!

 

[crane]

JJ too bright ? strange... like Old BF Shred if find them "high"-less.
I find JAN philips tube very bright, you probably won't like them. Try a Mullard reissue, it could be the one you're looking for. But it's a particular tube, you could love it or hate it. Don't hesitate to try every places for him (V1 to V... how V in the MkV ?).
You can ask for a high gain version (some dealers have this option).

 

[scott from _actual time_]

i'm almost positive there's nothing wrong with the amp. the Mark V just seems to sound rather bright, to more than a few people, and especially with the stock JJs.

i'm running pretty dark speakers, Celestion Classic Lead 80 and a CL80 clone, and i've already swapped the 6L6s for russian 5881s. i'm running the Presence from 8 o'clock to off, and it's still pretty bright.

the Mullard reissue--do you mean the New Sensor one? i could certainly try one of those. or do you mean the Groove Tubes one that is sold out everywhere? i doubt i could get my hands on one of those.

 

[crane]

I mean the new sensor reissue.
Otherwise you can try a NOS Mullard 12AT7WA (20-30$), not very bright, fantastic cleans ! But if you like lot of gain it could be unappropriated.
Note that the old and reissue have nothing in common, especially their sound.

 

[212Mavguy]

Just about any tube will sound at least somewhat bright when it is brand new. For a thick sounding lead tone with a smoother, less harsh top end try a well used old stock Mullard shortplate 12ax7 or a vintage REAL Tung Sol long grayplate 12ax7. Sounds like your amp has a pretty bright sounding circuit, and a very well used, vintage tube will roll off the highs a fair amount. Some of the old Mullards and Tung Sols sound great without being excessively microphonic, but it might take getting a few to get a really saweeeet one.

My Maverick was from the 90's and the 12ax7's that came with it were Chinese...before I yanked them and replaced them with a mongrel mix of top quality vintage old stock 12ax7's handpicked for each position...

It sounds more like a Mesa should now than when it had the stock tubes.

If you are using non Mesa tubes in your amp it could cause a warranty issue if it were sent to Mesa for servicing during the warranty period with a non Mesa tube installed in it. :wink:

 

[scott from _actual time_]

For a thick sounding lead tone with a smoother, less harsh top end try a well used old stock Mullard shortplate 12ax7 or a vintage REAL Tung Sol long grayplate 12ax7. Sounds like your amp has a pretty bright sounding circuit, and a very well used, vintage tube will roll off the highs a fair amount.

If you are using non Mesa tubes in your amp it could cause a warranty issue if it were sent to Mesa for servicing during the warranty period with a non Mesa tube installed in it. :wink:

how are those vintage Mullards or Tung Sols usually in terms of gain? i play rather high-gain sounds, and i like having tons of gain available if i need it.

yep, i know about the Mesa tubes and warranty issue. i'm keeping all my stock tubes in case something happens and i need to swap them back in. :wink:

 

[212Mavguy]

Unless you run your amp with gain dimed to the max frequently there should not be a significant problem. Only way to know for sure is to get 'em and roll 'em.

Even old 12ax7's testing at the lower limits of good or below good :shock: in a tube tester can put out lots of gain, more than I thought before I got my Hickok Cardmatic tester. You might be surprised how much gain you can get out of a vintage 5751 such as a GE grayplate.