Nos tubes 5:50

[gadgetfreak]

I put in an old Nos Rca 12ax7a and it immediately went microphonic on me, this tube was absolutely fine in my deluxe reverb, anyway other than being bummed out that it didn't like being in my express, has anyone else tried nos tubes in there amp?

I have the feeling this amp is engineered for new production tubes and that is what I'm sticking with, I just put a big order in with Doug to have some winged c's and multiple different 12ax7's to play around with. I didn't buy the so called 5:50 cocktail of tubes but just a bunch and I will see what works where the best. I know Doug meant that as a starting point so it's not gospel, you don't have to follow it to a tee, espcially since most of us have discovered that V2 is 1st gain stage and then v1 and so on. Also he recomends a Sovtek Lps in the p.i slot which is usually the last preamp tube but in this amp V5 is the reverb driver so remember this when swapping out your pre amp tubes, you might yeild better results putting your LPS in v4, I totally agree with Doug on that tube and have been using it for years in p.i positions. It's a great tube and can also work well as a starting gain stage tube, in other amps I have I immediately noticed a difference swapping in that sovtek lps.

So anyways if anyone has any stories good or bad on there nos tube woes let me know, I think I will keep my nos for my fenders and use the new ones for the mesa. Peace

 

[gadgetfreak]

I don't know what happened the tube works fine in there now :lol: Sound's freakin good to, I just picked up a couple for 10 bucks each on the bay, test results were 129/121 with 130 being the maximum and 70 the minimum, I see a lot of cheap nos 12ax7a's on the bay lately for cheap,always a gamble but gambling 10 bucks is nothing compared to say 50 which most people want for a nice branded Rca 12ax7a. Got my eye on a couple sylvania's for 30 bucks for 2 of them, test 130/130 in mint boxes, that's a steal. I'm not worried about it cause I'm the only one talking to me about this thread anyway

 

[mcbain]

I'm not worried about it cause I'm the only one talking to me about this thread anyway

:lol: :lol: :lol: As long as your not changing your voice to do it, you're fine!


So the tube started out microphonic right away, but then corrected itself naturally?!? Interesting to say the least.

You mentioned that you feel the amp likes new production tubes better, and ordered a ton from Doug's. Hows your swapping & experimenting with those going? I'd rather not spend all my disposable income on NOS tubes, so I'm definitely taking Friday's paycheck and ordering some new production ones.

MY goal is kinda the opposite of yours, I'd like to tame the modern sound/gain by about 10%. Nothing crazy, just smooth the overall tone of the gain a bit. I could probably do that with just better tubes right?? I have no idea if a cocktail of 5 different types from Doug's would be better, or a gold pinned Mesa Express set from Eurotubes. Let me know what you think.

In the case of Power tubes, what could you recommend thats a bit less expensive than the SED Wing's Cs you've been using? I don't play loud enough to benefit from power tube distortion, so I'm open to other suggestions.

 

[jpotts05]

From what I have read on this board and others, putting a 12at7 in the PI slot (v4) may just tame the gain just the way you would like.

 

[gadgetfreak]

Imo I would use a 5751 to tame your amp, a lot of guys use a 12at7 but besides being a lower gain tube it has different current as well. Wether or not it will mess your amp up Idk but I wouldn't take the chance when you can buy a 5751 which is 70percent gain,, a 12ax7 is 100percent gain.

If I were you I would buy a 5751 for V2,JJ in V1 because there not as much gain as say tungsol or electroharmonix tubes. You can get some nice Tungsol 6l6's for your amp for half the price of the winged c's and they are excellent tubes imo,, I have used them in bogners,fenders, and mesa. Never a let down. Tell you the truth I will probably get them again for my 5:50 next time, I love the SED's but I don't play at gig volume lately and I'm not really noticing a huge difference when just jamming at house level. I do crank up a couple time's a week but not like I used too.

So if your looking to get some nice tone and not break the bank get a 5751,JJ low distortion,Sovtek Lps for V4 and leave your 2 other mesa tubes in there and see how that sound's. Why break the bank when you don't have too, Really you could just try the 5751 and the new 6l6's and see how you fare, I would try that first unless your existing mesa 12ax7's are really old and of the chinese brand. If you have the better mesa tubes they will say Russian 2 on them, those are e.h's and great tubes as long as they are still doing there job.

Do you have a lot of noise and hiss, that's one thing even though I put high gain tubes in my amp, the amp is silent for hiss but still growls like a beast when pushed. So i have the best of both worlds for what I do.

I don't know where you buy your tubes but you can get a nice Jan 5751 for 29 dollars u.s.d on Dougs site, he carries the tungsols as well.

Btw I have no affiliation with Doug at all, just a faithful customer, I have never been let down with his products or service/shipping/handling.

Don't hesitate to email him and ask him the same questions and he will give his opinion which is usually on the money. Good luck let us know

 

[Don]

I've got a good supply of old tubes but was never really tempted to put them in the Express! I guess I'm saving them up for my tweed Deluxe clone and Vibrolux Reverb. It just seemed like the Express worked fine with recent tubes.

 

[gadgetfreak]

I agree Don and posted that several times, I'm more than happy with current production tubes in this amp. I have some old fenders as well and they really benefit nice from the older ones. I did try a Rca in my mesa and it was microphonic, tried it again and it was fine. weird,, works in my fender flawlessly

 

[gadgetfreak]

Just scooped up another nice Rca 12ax7a for cheap money,, tested 130/130 with 130 being max and 70 min. I put that in V1 and the tungsol in V2, Holy **** man does this thing sing. I have the best tone going today than I have ever had out of this amp. The sustain and harmonics from just touching the strings differently is so amplified. I swear tone sound's like it changes day to day sometimes even using the same tubes,speakers,guitars what have you, but i am leaving this amp alone until I hear something change. I am so f'ing pleased right now with how this bird sings I am just giddy. That is one awesome Rca and the cheapest one I've ever bought, less than 20 bucks shipped. Like I have said over and over you win some you lose some, today is a winner,, I didn't even buy the tube for this amp, I bought it for my deluxe but I just wanted to see how it sounded,geez I can't get over it. Can you say Creamy overtones.. Time to shutup and get back at.

 

[sevycat]

I changed out the V1 and V2 with NOS RCA12AX7A preamp tubes and my express 5 50 is better for it. Worth the money, I am happy with the tonal results and how it works with my single coil pickup guitars.