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Time for Power tubes; EL84s

Started by Dante, May 15, 2023, 09:19:45 AM

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Dante

Hi Y'all,

Just played a great gig on the patio of a local brewpub last Friday night. The breeze kept the hot temps from killing us, and put a nice layer of dust on all our equipment, since there was an empty lot next door. My amp has a plexiglass front, so I could easily see all the dust inside the next day. I took the amp apart and dusted it out.

It was then that I realized my tubes were all Groove Tubes - all the preamp tubes and power amp tubes. All this time, I thought I saw the red circle on each tube as a JJ, but it was the GT logo.... I'm pretty sure there are better options out there.

Not that I've been unhappy at all with the sound of that amp, it can do everything, very versatile. I just think I'll try some different EL84s in the power section first, to see if I get any clean headroom (that's about the only drawback, it's a struggle to get clean headroom with some guitars/pickups).

I have a boatload of preamp tubes I can try, but one thing at a time....let's swap out those power tubes

I'm leaning towards some Tung Sols, also looking at JJs and TADs. The JJs are notorious for sounding great and dying quickly, but they're cheap so you can buy extras. The Tung Sols are probably getting the nod so far

Harley Hexxe

#1
Dante,

    Personal choice: TAD

     JJs, like you said. cheap but die quickly. I'm hearing through the grapevine that Tung-sols and EHX are just rebranded JJs, but I don't know that to be a fact.

     BTW, How are the cabs working out for outdoor gigs?
I only have two brain cells left, ...and I'm saving them for the weekend!

Dante

I have no problem with TADs, I believe I can get them from TubeDepot

Cabs; Working beautifully, drummer is very pleased ;) Thanks man

rnolan

Hey Dante, nice little setup and range of guitars to pick from  :whoohoo!: .  Are you sure the wedges have enough power (2500 w)  >:D .  New Sensor do the Tung-sols last I looked (so being Russian, may be hard to get??). EHX are definitely rebadged, probably JJs but maybe Chinese??.  Interesting with the GTs, when I opened up my Carvin TS100 it has all GTs (4 x 12 AX7s and 4 x 6L6s), they sound fine (nice and clean) and look really nice.  When I eventually retube it I'll probably go for Mullard long plate 12AX7s and Mullard EL34s.
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

Harley Hexxe

Dante,

   I'm glad that worked out with the cabs, and also that the drummer is happy with it, but the most important thing is; does it still fill the air with enough guitar out in the open. It seems like it does. Anyway, it was a cheaper fix than buying new speakers.  :thumb-up:
I only have two brain cells left, ...and I'm saving them for the weekend!

Harley Hexxe

Richard,

     Doesn't New Sensor also make JJ's?

     It's hard to keep track of who makes what these days :crazy:
I only have two brain cells left, ...and I'm saving them for the weekend!

rnolan

#6
Hey Harley, JJ's are made in Slovakia.
(JJ Electronic, s.r.o is a Slovak electronic component manufacturer, and one of the world's remaining producers of vacuum tubes. It is based in Čadca, in the Kysuce region of Slovakia.)

So I think the manufacturers are: 
Slovakia (JJ's) 
China (there's quite a few including TADs IIRC)   
Russia (New Sensor brands, Mullard, Tung-sol, EH, etc. They bought a bunch of brand names) but (On March 11, 2022, Russia imposed a ban on the export of some 200 goods in response to the sanctions imposed on it over the current conflict in Ukraine. We have confirmed that the ban applies to our seven brands of Russian tubes. Currently, the ban is set to remain in effect until the end of the calendar year).
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

Harley Hexxe

Hey Richard,

    Okay, JJs are former Czech Republic, got it.
    As for the Mullards, the last several sets I've bought of those have been unimpressive. In fact, pretty generic sounding and not at all like Mullards. So they can keep their stock to the end of the decade.
    The Chinese have come up in their quality, even though their tubes don't last any longer than the average life expectancy of modern day tubes.
I only have two brain cells left, ...and I'm saving them for the weekend!

rnolan

Hey Harley, the original NOS Mullards (not that I've bought any as they are so $$$ive) are quite different (or so I believe) to the New Sensor long plates I've been buying.  The New Sensor ones work great in my MP-2s and have been reasonably consistent.  I swapped a pair into a MP-1 also and they sounded way better than the EHs' that were in it, although it was a quick test at my Techs when I was picking up some stuff. 

I had heard the Chinese tubes were getting better, which is a good thing  :thumb-up:   Of note, since you have quite a few Fender amps, I went to a tube rolling thingy a couple of (or more) years ago (IIRC I did post about it).  He had a Marshall, a Fender and some other amps.  And, of the various tubes he rolled, the Svetlana and also Sovtecs worked really well, noticeably better (we all agreed), in those circuits (go figure  :dunno: ).  Then allegedly Marshall used Svetlana winged C tubes for may years... until they stopped making them in 2012.  I think New Sensor bought that name as well?? 

Then what's in a name, MG were great English sports cars, now the name is being used for cheap crappy cars that have no resemblance to the original brand.
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

Harley Hexxe

Richard,

   I only have four tube Fender amps now, I sold all the others years ago.
   From lowest to highest wattage:
    1973 Vibrolux Reverb
    1971 Twin Reverb
    1972 Twin Reverb
    1970  400PS

    Those will cost me enough in tubes.
I only have two brain cells left, ...and I'm saving them for the weekend!

Dante

NTD!! New Toob Day

I received my TAD EL84s and dropped them in. Played at a low volume for about 30 minutes, no real noticeable difference, but I know they're fresh. I'll wait  until I've run them for 20 hours or so to make any assessments.

Since I had the head apart, I started rolling preamp toobs too - he he  >:D

Here's what I found inside:
V1: Sovtek 7025
V2: Mesa 7025 STR 12ax7a
V3: Mesa 7025 STR 12ax7a

Here's what I ended up with:
V1: Tung-Sol 5751 - Balanced, tested for low noise/microphonics
V2: Mesa 7025 STR 12ax7a
V3: Mesa 7025 STR 12ax7a

That Tung-Sol made a huge difference. I had another one to try in there (Jan-Phillips) but didn't even bother, this sounds so much better. I believe my clean tones are a bit louder (always a good thing) or just clearer. I've had that tube for awhile now, saved it for something like this.

I tried some others in the V2 & V3 positions, but nothing sounded as good as the Mesas I had in there already. I liked the gains in this amp already, just wanted to experiment while I had it cracked open.

I tried a matched set of Selected TAD ECC83s, but they didn't float my boat. Kinda flat sounding TBH. No pizzaz

Then, I had a mismatched set of a Mesa STR 12ax7a (I think this is an older version of the ones I went with, they are different) and a Sovtek 12ax7WXT. I tried each one in each spot, one combination was fizzy, the other was a bit low gain, but not terrible. Again, not as good as before.

So there you have it folks, a whole new re-tube for the Grandmeister Deluxe 40 (well, two preamp tubes stayed). I feel so refreshed  ;D

Harley Hexxe

Dante,

    Is the amp self-biasing? That's pretty cool if it does.

    You need to borrow my tube tester to check out what you're running.

    I used to take that with me when I'd go shopping for tubes, just to be sure I wasn't buying duds right off the shelf. I don't think they liked that too much at the music stores when I did that. Hah!
I only have two brain cells left, ...and I'm saving them for the weekend!

Dante

#12
QuoteThe GrandMeister 40 features Tube Safety Control, Hughes & Kettner's version of "No Biassing Required." Go ahead and swap tubes if you like (or let your tech do it if you're not so inclined). LEDs on the rear indicate tube health over their life, and whenever you should choose to swap tubes, the amp automatically and constantly biases/re-biases itself. Nice!

from 2019
https://musicplayers.com/2019/05/hughes-kettner-grandmeister-40-amplifier/

rnolan

#13
Hey Dante, that is really cool  :thumb-up: .  So that's really interesting about the Tung-Sol 5751, great to hear it sounds good.  So "Balanced" usually means the 2 triodes are equal/balanced.  The 5751 tubes have ~20% less gain than a standard 12AX7 (https://tubeaudio.com.au/tungsol-5751/) and the Tung-Sol's are made in Russia by New Sensor (same as the Mullards).  So no wonder your cleans are cleaner, V1 now has 20% less gain than the Sovtek.

Your Mesa STRs are most likely re-badged JJs, Mesa also do SPA 12AX7s, al bit more expensive than the STRs and usually have a black rubber(ish) shrink wrapped cover over the top covering the getter, I think to further cut down microphonics.  Mesa tubes here in Oz cost about double  :-[ . The STRs and SPAs work really well in MP-1s. 

V3 is most likely the phase splitter, one triode drives each side of the wave/signal (+/-) for the Class B output tubes.  You could try a 12AT7 or 12AU7 in V3, less gain but higher current than 12AX7 so drives the output tubes a bit harder  >:D (if that's a sound you like).
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

Harley Hexxe

I didn't know the H&K amps did that. Now I'm wondering how many of their other amps do that. I'll have to take a look at their new line up.

That's a cool feature. I was thinking it would be nice to have at least one half stack with a 4x12 cab again, but I haven't been looking for a couple of reasons:

1 I'm not hip on amps that will need to be biased every time I have to change power tubes, because they are so much more expensive these days and they don't last near as long as they used to. Not to mention most amp techs around here don't know $hit about tube amps, even though they claim to.

2 I'm not sure if I want to buy a 4x12 cab, or just build one myself. That's because I'm not crazy about the speaker choices that come with cabs these days, and some of the choices I've seen at WGS look like they would be better than most of the Celestions that are coming in those cabs.
I only have two brain cells left, ...and I'm saving them for the weekend!