TriAxis Tubes and where to get them?

[bjoneill74]

I have a TriAxis, a Lonestar 2x12, and a studio .22.
I've read that changing the 12Ax7's in the TriAxis to 12aT7's (NOS) can yield better/fatter sounding results.

I've changed the preamp tubes a few times and have always just used the tubes that I've ordered directly through Mesa, but would like to experiment a bit. Most of my cleans are Lead 1 Green, while lead/solos are Lead 2 Orange and Crunches Lead 2 Red.

What tubes work best for a wide variety of styles from singing blues solos, to jazzy passages all the way to pretty darn saturated crunch tones?
And where should I look to get them? how much will this generally cost me?

 

[Cheez]

I really, really, really liked an RTF ECC83 in the MkI modes for bluesy & "pushed clean" sounds. Gorgeous. about $40. Actually, I think I may have had it in the V1 spot...

JJ 12AX7s did the trick for most of the other positions. $10 each & big improvement over stock sinos.

 

[Guitarzan]

FatBoy135 highly recommends this setup...I can't personally say ..I don't have a triaxis...but this seems to be a well tested formula...

My triaxis tube setup for the moment is:
V1-Eh gold
V2-Eh gold
V3-JJ-ecc83s
V4-JJ-ecc83s
V5-JJ-ecc83s//Svetlana 12ax7

 

[bjoneill74]

awesome, thanks for the replies.. I'll check them out.

 

[Timbre Wolf]

You could read this thread. Its a complicated topic. Consider using different tubes, in Triaxis' 5 tube positions, as they perform different functions.

As for 12AT7, I still recommend '80s Mullard 12AT7WA/CV4024, and they'll provide you with a nice fat, liquid, clean and open character when used in Triaxis V2 (main input for cleans and Lead 2; drive for Lead 1). I highly recommend Doug's Tubes for these, at $20 each (=bargain), and Doug Preston is a very helpful and friendly guy. I would not recommend using the CV4024 throughout the preamp, though.

If you have more questions after reading that long-winded thread, please ask. The more specific detail you can describe about what you want, and with which Triaxis mode, the better I (and others) can help.

- T

 

[bjoneill74]

Timbre Wolf,
I did read that thread.. it's what ultimately made me decide to join this board. The information there was very usefull, but it seems that the thread died in 2005 sometime. I figured I'd post to see if anything new was recommended and it's quite apparent that these sorts of decisions are very much a matter of opionion/taste or lack thereof.

I've simply used the stock boogie 12AX7's and 6L6's since getting the TriAxis and the 2:90.

I've changed tube a number of times, though I've yet to open the 2:90 to change the 3 12AX7's in it.

As stated before.. I mainly use the Lead 1 Green mode for most clean tones and I have the gain set to where it just starts to break up a bit when you dig in (but just barely).. I like this to be warm and shimmery at the same time.. bass, mids and trebles are pretty well balanced as far as EQ goes. The Lead/Solo tones are generally Lead 2 yellow (I have this fairly scooped as the the mesa 4x12's were very mid heavy to my ears) when I back off of the volume on the guitar or volume pedal, the sound cleans up and gets to be more of a shimmery sounding tone, when the volume is up, it fattens up, but cuts at the same time.. (think Steve Rothery, Dave Gilmour, old school Chris DeGarmo etc..) and finally the crunch tones I use are mainly the Lead 2 Red (again pretty scooped and a good amount of gain ala John Petrucci, Metallica at times).

Thanks much for your earlier reply. I find it all very helpful and enlightening.

Cheers,

Brian

 

[Timbre Wolf]

Thanks, Brian, I'm glad you found my tube ramblings useful. It is very much a matter of taste, and it really helps if you've got a collection of tubes to draw from when you're feeling experimental.

For what its worth, I also favor Lead 1 Green for my clean to overdrive transitions, and after countless hours of experimentation, nothing has unseated the Raytheon black-plate 12AX7A - Mullard CV4024 combo for me. And I've been busy trying. The only close second to the Raytheon, which I didn't mention previously, is the '50s KenRad black/silver-plate/D-getter 12AX7. The KenRad breaks up just slightly later, and has somewhat more full low-mids. I use the KenRad 12AX7 in another amp (Lexicon Signature 284).

You can still get Raytheon black-plates for around $10 each, on eBay. They're often labeled Baldwin, Schoeber, or Lowrey, for the organ companies that used them (and selected them for low-noise). These are used, but they almost exclusively test very strong - better than new, and a a fantastic bargain. Tubemonger is the only dealer I know of who sells these, and again, they are the lightly-used, test as new samples (no one sells NOS). Note the shiny black plates, and the unique partial upper-mica structure, as you can see in Tubemonger's photo - this will help you i.d. these tubes if you bid on eBay.

I also really love Lead 2 Yellow for soaring solos. This is where the CV4024 - long-plate Mullard 12AX7 combo comes to play, and it is just amazing!! Though I never seem to use the same preamp tube type twice in any amp, I could probably live in a world where the Mullard long-plate 12AX7 was the only choice. I love its responsive bark, and stellar clarity. But please, don't make me make that choice!

The most reliable and inexpensive source for long-plate Mullards I know of is SND Tubes. These are used, tested good (don't worry - they last a very long time), without clear Mullard labels (again, don't worry - the etch code "f91" or "f92" is all you need, unless you're "collecting") for $40. EBay is a crapshoot, but you can get bargains there as well - I've gotten several fine ones for less than $20 each.

So there's really not that much different going on, as far as my setup goes. I've probably tried a dozen new (to me) preamp tubes types since, and they're waiting in storage until I need their particular character in a new amp.

Cheers back to you (where's the beer stein emoticon?)

- T

 

[fatboy135]

FatBoy135 highly recommends this setup

thanks for the banner
I recomend at last a svetlana on V5.
Anyway I don´t recomend to swap a 12ax7 by a 12at7 becuase they are different features on that tubes and you must to change a bit the values of the cathode and anode resistors. Seeing the 12ax7 the only tube that could be replace it directly is the 5751, try one of them.

 

[bjoneill74]

Thanks, Brian, I'm glad you found my tube ramblings useful. It is very much a matter of taste, and it really helps if you've got a collection of tubes to draw from when you're feeling experimental.

For what its worth, I also favor Lead 1 Green for my clean to overdrive transitions, and after countless hours of experimentation, nothing has unseated the Raytheon black-plate 12AX7A - Mullard CV4024 combo for me. And I've been busy trying. The only close second to the Raytheon, which I didn't mention previously, is the '50s KenRad black/silver-plate/D-getter 12AX7. The KenRad breaks up just slightly later, and has somewhat more full low-mids. I use the KenRad 12AX7 in another amp (Lexicon Signature 284).

You can still get Raytheon black-plates for around $10 each, on eBay. They're often labeled Baldwin, Schoeber, or Lowrey, for the organ companies that used them (and selected them for low-noise). These are used, but they almost exclusively test very strong - better than new, and a a fantastic bargain. Tubemonger is the only dealer I know of who sells these, and again, they are the lightly-used, test as new samples (no one sells NOS). Note the shiny black plates, and the unique partial upper-mica structure, as you can see in Tubemonger's photo - this will help you i.d. these tubes if you bid on eBay.

I also really love Lead 2 Yellow for soaring solos. This is where the CV4024 - long-plate Mullard 12AX7 combo comes to play, and it is just amazing!! Though I never seem to use the same preamp tube type twice in any amp, I could probably live in a world where the Mullard long-plate 12AX7 was the only choice. I love its responsive bark, and stellar clarity. But please, don't make me make that choice!

The most reliable and inexpensive source for long-plate Mullards I know of is SND Tubes. These are used, tested good (don't worry - they last a very long time), without clear Mullard labels (again, don't worry - the etch code "f91" or "f92" is all you need, unless you're "collecting") for $40. EBay is a crapshoot, but you can get bargains there as well - I've gotten several fine ones for less than $20 each.

So there's really not that much different going on, as far as my setup goes. I've probably tried a dozen new (to me) preamp tubes types since, and they're waiting in storage until I need their particular character in a new amp.

Cheers back to you (where's the beer stein emoticon?)

- T

Ok so you recommend the 12AT7/CV4024 in V2 and the Raytheon Black plate 12AX7A in V1?
I'll give that a go.. the $10 - $50 per tube deal doesn't bother me so much. I'd probably prefer to go straight through a dealer of some sort.. rather than deal with ebay, but will if I must. You've definitely got me thinking that I should just study up and collect a bunch of tubes, try em out, but it helps and is interesting to see what others find work well.

Is it ok to use the 12AT7 (mullard) in the TriAxis.. There's another reply that seems to suggest that 12AT7's might not do well in the TriAxis.. Is there something else that needs to be done/changed on the preamp to work properly with a tube other than a 12AX7?

Thanks again for the remark.. and yes.. defly time for some beers...

Brian

 

[bjoneill74]

FatBoy135 highly recommends this setup

thanks for the banner
I recomend at last a svetlana on V5.
Anyway I don´t recomend to swap a 12ax7 by a 12at7 becuase they are different features on that tubes and you must to change a bit the values of the cathode and anode resistors. Seeing the 12ax7 the only tube that could be replace it directly is the 5751, try one of them.

Fatboy 135,

Thanks.. So you are saying that a 12AT7 isn't a good idea?
I should stick to 12AX7's??

Thank you for the suggestion on the svetlana on V5, I'll give that a try, along with the EH Gold tubes and others listed on your behalf above.

Brian

 

[Timbre Wolf]

Is it ok to use the 12AT7 (mullard) in the TriAxis.. There's another reply that seems to suggest that 12AT7's might not do well in the TriAxis.. Is there something else that needs to be done/changed on the preamp to work properly with a tube other than a 12AX7?

I've been running my Triaxis for over three years with the Mullard 12AT7/CV4024 in V2, and it works better than ever. I've tried many 12AT7s, and other tube types, such as 12BH7, 12AU7, E180CC/7062, 5751, and 12BZ7 in every position in the Triaxis, and none are problematic. Some of these tubes draw more current than the 12AX7, but Mesa's over-engineering allows for these substitutions (even though they explicitly prohibit it for warranty service).

It is helpful to use caution, and knowing a little bit of theory helps one in this. Some people get stuck in theories, or get confused by them, and talk about things they have no experience with. But in my book, there is nothing like direct experience. As always, on the Internet especially, it helps to have a finely-tuned b.s. meter. And no, you don't have to swap out any electronic components, other than the tubes - no soldering required!

I'd like to hear back from you, as you experiment. Also, pm me if you want to further discuss tube types to try, some I'd recommend to avoid, buying tips, etc.

- T

 

[fatboy135]

Theory saids to me that 12at7 and 12ax7 are not directly swapable you will need to change a bit the resistors that fixes the bias point of the tube, you could also test like TW saids, just to experiment, but remember not all the wheels that are rounded could swap into your car, and not all the noval tubes could be place on a 12ax7 socket. I instead recomends you to try a 5751 before a 12at7, they are very closer but the 5751 will work very well.
P.d: I had tried a lot of 12at7 on many tube amps and the best position for that kind of tubes is in reverb circuits.

 

[Russ]

12at7 in reverb is a good idea...

The Mark IVa has a 12at7 in the reverb socket.

I have found some success in taming Marshalls but I am unsure what it would do to a Mesa or even in a rack piece. With my old rack stuff I never had trouble so long as I stayed with what was intended for the circuit. This is not to say that a 5751 or 12at7 would not work but I found that the rack stuff seemed a little more sensitive than a regular head. As far as the other noval tubes go, the 12au7 would severely neuter you triaxis. The gain comparison for that tube is down at 20% of what you would get from a 12ax7. The 5751 would be much closer with a gain factor near 70% whereas the 12at7 is nearly 60%. A 12ay7 would give you around 45% while a 12av7 would be nearer to 40% of your intended gain. I don't think I would try a 12bh7 because it really isn't quite the same either. It is a med gain dual triode but it is much taller not quite the mini that the others above are. If I am not mistaken the 12bz7 is another taller tube type.

If you decide to experiment, be sure to take it easy until you are sure that you are doing no damage. Remember that Mesa is not going to support your tone quest in their warranty so be careful by all means.

 

[Timbre Wolf]

12BH7 and 12BZ7 are both 3/8" taller than a 12AX7, as are E180CC. The back of the Triaxis is open, so tube length is not an issue with these tubes. I've experimented with low-mu tubes (12BH7, 12AU7, E180CC, etc.) and would not normally run them in my Triaxis (12AT7 is as low as I go), but would not hesitate to do so for recording purposes, in order to extend the shades of clean-to-breakup. I run both the Triaxis and my 20/20 power amp with 12BZ7 in them (TXS: V5, 20/20: V1), and have for years, now.

If you decide to experiment, be sure to take it easy until you are sure that you are doing no damage. Remember that Mesa is not going to support your tone quest in their warranty so be careful by all means.

I encourage informed experimentation, as well. Thanks for the reminder, Russ - step outside of Boogie's stated tube parameters, and you're on your own. Fortunately, after years of experimenting, I've not had need of my Triaxis warranty (which expired probably 12 years ago).

- T

 

[bjoneill74]

yep.. My Warranty has long expired.. if the TriAxis gets damaged.. I'm paying to have it serviced/replaced anyway.

I did order one Mullard 12AT7/CV4024
and a Raytheon 12AX7 Black-plate.

I'll see what they do.

with the 12AT7 in V2.. where (which modes) can I expect gain/distortion drops?
I do tend to use the Lead 2 Red for crunches and while I wouldn't call it buzzsaw crunch.. it's got a fair amount of crunch to it.

Brian

 

[Timbre Wolf]

yep.. My Warranty has long expired.. if the TriAxis gets damaged.. I'm paying to have it serviced/replaced anyway.

I did order one Mullard 12AT7/CV4024
and a Raytheon 12AX7 Black-plate.

I'll see what they do.

with the 12AT7 in V2.. where (which modes) can I expect gain/distortion drops?
I do tend to use the Lead 2 Red for crunches and while I wouldn't call it buzzsaw crunch.. it's got a fair amount of crunch to it.

Brian

V2 is always in the circuit, one way or another, so you'll likely have to make adjustments to every preset. Stretch your hands frequently to avoid tweaker's finger :wink: V2 is the clean mode input tube; in Lead 1 it is the drive tube (with V1 as input), and Lead 2 modes it is the first input tube.

I have a difficult time getting Lead 2 Red to not crunch, so I don't anticipate any problem for you dialing in what you need.

If you're truly seeking cleaner signals, I'd recommend a (black-plate) 5751 in V3. It clears the cobwebs (less compressed, less distorted) in a bold way, in my experience.

I'd like to hear your impressions, once you've made the change.

- T

 

[bjoneill74]

will do..

I'm looking at the tubes that arrived and the numbers on the Raytheon might not be what I was looking for.
The label is actually Raytheon... not Baldwin or anything else.
There is a longer plate which is shiny/black.

The only numbers I see are 280
then 62-13 under it.

USA AS

???

Brian

 

[Timbre Wolf]

will do..

I'm looking at the tubes that arrived and the numbers on the Raytheon might not be what I was looking for.
The label is actually Raytheon... not Baldwin or anything else.
There is a longer plate which is shiny/black.

The only numbers I see are 280
then 62-13 under it.

USA AS

???

Brian

That's the same Raytheon 12AX7A I know and love. The shiny black plates have squared-off tabs (not rounded) protruding through the mica disks. Check out the partial mica that's between the upper mica disk and the round getter wire, as confirmation. "280" is the EIA code for the manufacturer (Raytheon), and the "62-13" means it was made in the early spring of 1962, which fits right in the time window during which these were manufactured. There is an earlier Raytheon black-plate 12AX7 with a square-getter, and, in my experience, it is nearly identical character to the 12AX7A/halo-getter model.

For what its worth, the only other 12AX7 I know of with shiny black plates that are long (17mm) is the Sylvania. It'll have a square getter, and the plate tabs that protrude through the mica disks will be more rounded. RCA black-plates are dull black, and KenRad (or sometimes marked "GE" = same) are also dull, but they're black and silver, as if some of the black (carborundum) has flaked off. These are all great 12AX7s, but they've got different characteristics than the Raytheon.

Hope you enjoy it!

- T

 

[bjoneill74]

excuse me as I'm not as knowledgeable on these things.

I'm assuming the getter is the thing that sort of hangs above everything else (in this case it's a ring or a halo). It doesn't seem to have the extra mica thing that you are talking about. I'll have to take a picture of this tube to post or something.
The other thing is that it seems only to say 12AX7 and not 12AX7A.

The plates are indeed longer and definitely shiny compared to other 12AX7 tubes that I have. The tabs protruding through the top mica disk are indeed squared off.

It actually does seem to have a bit of micah further up, but not like the pictures on the site you sent me to check them out.

Are these the correct ones.. yeah they look similar to what I got.
http://www.tubemonger.com/mm5/merchant.mvc?Screen=PROD&Store_Code=T&Product_Code=223&Category_Code=83

***another edit***
I did a quick photoshop thing of the tube part I think you are talking about... the partial mica ring..

http://www.gerbhost.net/~bjoneill/tewb/tewb.jpg

I tried to highlight it in pinkish/red..

My tube actually does have that.. it's attached to the middle protruding pin on each side, but this tube seems to have that bit on the inside of the tubes rather than running on the outside as it seems in the pic from tubemonger.
It's also much smaller as the pics on tubemonger are larger than life.


Brian

 

[Timbre Wolf]

I tried to highlight it in pinkish/red..

My tube actually does have that.. it's attached to the middle protruding pin on each side, but this tube seems to have that bit on the inside of the tubes rather than running on the outside as it seems in the pic from tubemonger.
It's also much smaller as the pics on tubemonger are larger than life.


Brian

The area you highlighted (in salmon) is what I was referring to as the partial mica. To me, it's shape is vaguely reminiscent of a paper clip. I don't know about the inside/outside question, but that part is basically what I was referring to, as another identifying feature of this tube. You've definitely got the right thing.

Here's a tube part diagram, f.y.i. What I called a mica disk, they called an insulating spacer. Although this is not a dual triode tube diagram (12AX7 is dual triode), I hope it helps: