12ax7s..more tube swappery and recommendations needed

JeffB

Let it B
Been playing around with pre tubes in the TM18. For now the matched JJnEl84s are working well, softened up the overall tone without losing any lows....though I will probably try some Mulard reissues in the near future.


For 12ax7s I have tried JJECC83s, the original ValveArt 12ax7b (shugang), a couple of Marshall branded (shugang something weird-shorter than most x7s, and a JJecc83s), a old GT 12ax7c (shugang?, sino?),and a russian Svetlana about 5 years old I ran in my Vox VT amps. Trying them all in various combos. Obviously not a selection of the cream of the crop, but...

The JJ 83s is just not my thing...they really chop off low end, and add strident high end. Really thins the amp out.

The Shugang Bs that came with the amp, are more gainy and fizzy but have more girth than the JJs.

The GT12ax7c is muddy and compressed and also thins the amp out.

The Svetlana is noisy. A noticable increase in hum, but by far is the best sounding in V1. It is fat, open, with good detail and warmer than all the rest. Creamiest and vintagey-est. But I have no idea if the hum noise is because the tube is on its way out, or just typical..It was in my Vox VT15 for a couple or 3 years, but obviously not in the same capacity.

Any ideas on current production tubes that would be similar to the Svetlana? I probably will buy another 2 of them, but wondering if something similar/better out there with that kind of tone. Not looking to spend big money on NOS, just decent modern tubes.
 
Re: 12ax7s..more tube swappery and recommendations needed

I've had luck using JJ's before. I'm using GT 12AX7's in my amp now and they sound great. Not muddy at all. Tungsol's are definitely worth a try
 
Re: 12ax7s..more tube swappery and recommendations needed

The Jjs worked much better in my class5 for some reason.

According to The Tube Store, it seem sthe Tung Sol, Svetlana,.and EH are all part of the same family...EH being the crispest modern version, the Svet being the warmest, and the Tungsol falling in the middle for warmth, and is the most detailed/rich.

I pulled the Svetlana from V1 as the hum was freaking me out, lol. It did not sound healthy for the amp. Put the original Shugang Bs back in for now. If they were less gritty, I could probably live with them in combo with the JJ EL84s.
 
Re: 12ax7s..more tube swappery and recommendations needed

I've recently come around to the Mullard RI 12AX7 in V1. Before that, I was pretty happy with a Tung-Sol. The Mullard seemed to kill a bit of harsh high end, and there's something about the mids that tube provides that just works perfectly for me. The other thing I did was put a Ruby 12AX7AC5 HG+ in V2 to fill out the lower mids and bass. That combination has worked perfectly for me over the past six months or so.
 
Re: 12ax7s..more tube swappery and recommendations needed

I've recently come around to the Mullard RI 12AX7 in V1. Before that, I was pretty happy with a Tung-Sol. The Mullard seemed to kill a bit of harsh high end, and there's something about the mids that tube provides that just works perfectly for me. The other thing I did was put a Ruby 12AX7AC5 HG+ in V2 to fill out the lower mids and bass. That combination has worked perfectly for me over the past six months or so.

Sounds like maybe the Mullard and Svetlana are doing similar type thingsin V1. What amp do you have yours in?
 
Re: 12ax7s..more tube swappery and recommendations needed

The Mullard RI is a good tube. Warmer than most without making your amp sound like it has a blanket over the cab. It's got a lot of balls, too. Probably the only long-plate tube that doesn't squeal like mad when you use a lot of gain. I have been using one in the JCA22H I am starting to mod with some Penta C9 tubes and a JJ ECC803 in the PI. Otherwise, I like using the Tung Sol RI in V1.
 
Re: 12ax7s..more tube swappery and recommendations needed

The Mullard RI is a good tube. Warmer than most without making your amp sound like it has a blanket over the cab. It's got a lot of balls, too. Probably the only long-plate tube that doesn't squeal like mad when you use a lot of gain. I have been using one in the JCA22H I am starting to mod with some Penta C9 tubes and a JJ ECC803 in the PI. Otherwise, I like using the Tung Sol RI in V1.

This Mullard RI is starting to sound like what I am looking for.

Have you tried the JJ 803S yet? If not, you should.

I have not Ben. It is my understanding it is a clearer lower gain tube? Or am I thinking of something else? The TM is already super clear by nature,.so looking to go the opposite type direction. Open, but warm.

Edit- I was mistaken, but it seems to not be suggested for a V1 slot because of microphonics?
 
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Re: 12ax7s..more tube swappery and recommendations needed

The JJ 803 is a little more prone to microphonics than most, but it's still controllable. I used it in V1 of my PV XXX a lon time ago. Worked very well. The TungSol will definitely add some grind and crunch, as well.
 
Re: 12ax7s..more tube swappery and recommendations needed

looking to go the opposite type direction. Open, but warm.

You and me both. I've tried quite a few tubes: Chinese pres, JJ ECC83s, Tung Sols, EH... my favorite tubes to do the "open and warm" thing is unquestionably RCA 7025s, but a) they're expensive, b) difficult to find the real thing and c) even if you find the real thing it's almost impossible to find ones with no microphonics in loud combos. Argh, frustrating. I don't mind the JAN/GE NOS stuff either, but they lack the lowend presence and overall lack the balls or punch of the RCA. I really, really wish I could find a modern day equivalent (or something at least in the relative ballpark).
 
Re: 12ax7s..more tube swappery and recommendations needed

You and me both. I've tried quite a few tubes: Chinese pres, JJ ECC83s, Tung Sols, EH... my favorite tubes to do the "open and warm" thing is unquestionably RCA 7025s, but a) they're expensive, b) difficult to find the real thing and c) even if you find the real thing it's almost impossible to find ones with no microphonics in loud combos. Argh, frustrating. I don't mind the JAN/GE NOS stuff either, but they lack the lowend presence and overall lack the balls or punch of the RCA. I really, really wish I could find a modern day equivalent (or something at least in the relative ballpark).

I have a few of the grey plate RCA 12AX7s from the 60's and they are phenomenal. If the 7025s are "better", then to me, they would be the holy grail of tubes.
 
Re: 12ax7s..more tube swappery and recommendations needed

The silky high end of the Svetlana in clean is hard to beat, it's quite well angelical.
And, it does hi-gain also good.
Maybe you had a worn tube, I find them not so noisy.
There is no other tube that sounds equal to the Svetlana. Maybe the JJ ECC83S is the closer one but, the JJ can go harsh, while the Svetlana is silky.
BUT, if you like the Svetlana, I bet you will love the Mullard re-issue.
Is just as open sounding as the Svetlana, more even balanced, very linearly working and, loves to be pushed, where it delivers it's best. On the sweet spot and beyond is where this tube shines like no other new production ones.
 
Re: 12ax7s..more tube swappery and recommendations needed

One thing that has worked really well in a few of my amps, ESPECIALLY my Mesas, was a tube order like this: V1 Tung Sol RI. V2 JJ ECC83s High Gain V3-V4 Penta Chinese V5 JJ ECC803s

The Tung Sol sets the stage for a big, musical, but articulate tone. It's crunchy but fat. NICE harmonics. The JJ adds the bit of compression for sweeter leads/solos. The Chinese tubes are fairly neutral, a little grit and nice, clear power. I generally prefer long-plate tubes in the PI, and the slightly lower gain of the JJ 803s cuts a touch of compression out for a nice, articulate, open tone.

Personally, I don't think JJs are bad, but too many of them in a row can sound a bit boring as they do compress more than most other tubes. If V1 is the input tube for both dirty AND clean channels, it will offer up more clean headroom than other tubes.

The Mullard in V1 will be warm, powerful and thick.
 
Re: 12ax7s..more tube swappery and recommendations needed

It kind of surprises me how few people I read talk about the Mullard RI 12AX7s. It really is one of a kind. So are JJs, but anyone who's read any of my preamp tube posts knows where I stand on those. They stink.

If you haven't done any real tube rolling, I highly suggest you add a Mullard to your collection, because they really are different than the other Russian tubes.
 
Re: 12ax7s..more tube swappery and recommendations needed

The JJ 83s is just not my thing...they really chop off low end, and add strident high end. Really thins the amp out.
Thats odd, cos thats the opposite of my experience with jj ECC83s 12ax7 tubes. Perhaps the one you tried was old/worn out?

Anyways fwiw:
EH will add some hotness and a bit of grit and some power in the midrange. Low noise too.
Tung sol's will add some sparkle in the high end.
 
Re: 12ax7s..more tube swappery and recommendations needed

Anything is possible as they are a couple years old? But I have 3 of the JJ ecc83s, and one Marshall branded version and they all sound the same in thiis amp in V1. Bright, thin, hard/harsh. The Valveart( Shugangs) are much bigger, smoother, and tiny bit warmer. Which surprised me. The JJ EL84s however are a significant improvement over the originals.

Edit-wanted to add that when I was running the JJECC83s, I had to run my treble nearly off.when I put the shugangs or svet in I was back to my normal 10-11 oclock setting. Maybe all my JJs are bad, IDK.
 
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Re: 12ax7s..more tube swappery and recommendations needed

that doesn't sound like jj's. Usually they are the kind of tube where people turn the treble up a bit more and trimming off some bass.
There is a lot of people going round the internet saying preamp tubes don't wear out, but they definitely do..especially so in modern high gain/cascading gain amps where they get overdiven to within an inch of their life to give up the gain sounds that ar popular. The Phase inverter spot also in any amp is particularly hard working. If your tubes have been used in the past (possibly in a marshall?) then it it quite likely that they are well past their best.
Its definitely worth getting hold of a brand new/tested one and trying it out. All things being equal they should give a noticeable increase in headroom, bass and a smoother less gainy top end compared to pretty well any other tube on the market.
 
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Re: 12ax7s..more tube swappery and recommendations needed

Jeff, that's very different than my experience with JJ short-plates. To my ears, the treble is nearly gone, and there's a huge amount of gain and push in the low mids. When I put them in my amp, I lose a lot of clarity, chime, and upper mid response. I'm surprised to hear how different your experience is, but it could be the amp.
 
Re: 12ax7s..more tube swappery and recommendations needed

Yeah. I do not doubt that the tubes are toast..I ran 2 of them in the class 5 for 2 years. Those were brand new tested ones. I did not realize until.I went to replace the originals that one of the preamps was also a JJECC83s, and the EL84 was a JJ. I do know that the the new JJel84 and 83s' significantly improved the Class5.

Those two now sound like complete garbage. The other two...the marshall branded jj 83s, and another JJ 83s I had bought but never used in my VOX (cos it sounded like crap), should still be good. They all sound roughly the same though in the TM18. They are less full, have harsher gain characteristics and piercingly bright....brittle.

I guess they are all toast.

I think I will.grab the Mullard, another SVET, and a 803s to try.
 
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