Old tubes vs New tubes

My Melody I880 integrated has been running the same set of KT88's for several years now. Lately they started going soft, getting noisy, sometimes kind of a white noise, sometimes kind of a pffft sound, different levels, at idle never during play. Okay well they are shot.
Trigger warning: Tube amp voltage is lethal. Lethal means you could be killed. Seriously. Electricity is really really scary lethal. Heat too. Skin grafts hurt a lot. The following information is of a graphic nature. Do not continue if you are easily disturbed.
The tubes are really hot from music so I go out and get a cotton towel to change em out. There's an old set I keep around just in case. Lotta hours on these as well but curious to see how they compare I plug em in. Right away, faster than I can change a side anyway, there's this electric zapping sound and I look and see this really cool Tesla coil blue-white mad scientist electrical storm going on inside one of the tubes. Cool as it is I figure this is probably one of those times when less is more. Off goes the amp and off goes me looking for another set.

Ahh, here we go. Brand new (probably) Svetlana KT-88s. Plug em in. Power on. No zapping. No smoke. Okay. Back to Brother's in Arms, Side 3 of the MoFi 45 set.

Right away it seems like nothing has changed, no wait, it is a little more open and extended, little more detailed. The longer I listen though, its like someone's in there turning this great big knob slowly, ever so slowly, up and up and up. And this Gnome, he's got this control panel chock full of knobs- Bass, Midrange, Treble, Imaging, Palpable Presence, Detail, Dynamics, Punch, Slam, on and on, and he starts out scrambling like mad between them but then after a while he gives up and starts straining away slowly turning this one monster knob labeled EVERYTHING!

I love this guy! Within a few minutes its obvious the bass is more extended and a whole lot tighter. The highs are crystal clear, airy and free of mist. The whole presentation is so freakishly dynamic I can hardly believe it. There's a wood block, at least I think its a wood block, but every time he hits it it makes this CRACK! that is so powerfully there you feel it in your chest. I feel it in my skull! Which itself is impressive considering how thick my skull is! There's a bass line that's so articulately and precisely delineated its like you can tell the guy had his manicure at Gene Juarez and not the cheap Korean place. Knopfler is palpably present like never before, he just had a sip of Evian and not the sparking one either and yeah I know BIA is maybe the best MoFi of all time SQ wise but come on! 

Few minutes later I walk out and try and tell the wife about the blue-arcTesla tube. But she cuts me off. "What was that last? It sounded like a concert. It was BETTER than a concert! What did you do?"

People strain to hear differences between tubes. My wife heard this through the listening rooms closed solid core weather-stripped door. Before it sounded like a tube amp. Now it sounds..... amazing.


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I used to spend money on NOS tubes and have discovered some new production sounds superior IMO. I'm off the NOS carousel now.
In KT88’s I’ve run Svetlana, JJ, Tung-Sol, and Melody. At least they say Melody. But its a Melody amp, probably they screen it on, who knows who made the tube.

Before the Melody, in my Aronov we ran all those same brands of tubes, except that amp would run 6550 or KT88 so both were tried.

What I can say, its not that there aren’t differences between tubes. There are definitely differences between tubes. But to what degree? That is the question. My answer is, not much. I can get about the same degree of change by spraying anti-static, or demagnetizing. I can get the same or more by putting up just one HFT or sticking one ECT on the amp. A whole lot less than one Blue Quantum Fuse.

So the difference between a set of the cheapest JJ at $178 and the most expensive Tube Store at $272 is about $100 which is in line with other things one could do.

This is when comparing relatively new tubes. Obviously according to what I just posted, comparing really old worn tubes to new ones is a whole different story. A lot of what people are hearing rolling tubes may really come down to differences in age, warm-up, etc. Its not always that close but in my experience it has been.

Now with relatively new tubes (Tube Store matched JJ’s, actually the cheapest ones!) listening last night I heard a whole lot more inner detail, dynamics and good old tubey magic than my old tubes had been giving me. While tubes have proven reliable over the nearly 30 years I’ve been running them, still don’t like being without a spare set. So I just ordered a matched set of the Tube Store brand KT88.

I used to spend money on NOS tubes and have discovered some new production sounds superior IMO. I’m off the NOS carousel now.

The only one I am curious and might actually try is the EAT KT88 Diamond. At about $400 each a set is about what I paid for my demo no warranty Melody. Come end of year if all my necessaries are done, I’m flush, and the TubeStore guys are able to convince me, then maybe with all that I might give them a try.

Getting into that price range though, I still have my Aronov integrated. Something wrong, it blows fuses. When it worked though- magic! A lot of tube magic I think comes as much if not more from the transformers. Plus the Aronov has been modded with a lot of high end caps and stuff. One of those projects for when I have enough time and feel like learning to master the next new thing.
Miller, I agree the "transformers' in a tubed rig are arguably the most critical piece of a good sounding design. I still hear well enough that I can tell the differences in most tubes, when rolling. And especially the driver tubes.
The best vintage tubes are unobtainable, e.g., Tungsol RP 6SN7, Western Electric 300B or 437B, Mullard 13D6, Ei KT90, etc.

Many other vintage tubes are not better than new production. I like the EH 6SN7.
New matched set of TubeStore Preferred Series KT88s went in last night. TubeStore labels each tube with their matching number. When ordering I let them know my current set is 33, and so the ones they sent are 33. Sweet!

Bias hasn’t been checked in a while, and still hasn’t. Living the life! Caution to the wind! Blue spark! What?!? One of the new tubes went spffft (literally, I ran it through Goolag spel chek) and lit up with the same Tesla cool blue flash as the really old ones did recently. Which for a second had me frozen, fearful the lethal electric tube monster was about to burn my neighborhood down. But only for a second, and that was it. I remembered another guy saying this blue thing was a manufacturing deposit burning off and he could tell some tubes were good when they only gave a brief bit of this. So even though I’ve only seen it these two times it seems its nothing to worry about. Far as I know it hasn't happened again. As of this morning my house is still standing. Neighborhood too. Whew. But it was close there for a second. So be careful. Maybe hire an electrician.

Anyway the new tubes sound great. Not hugely great. Not like going from the near dead Melody tubes to the merely lotta hours JJ tubes. That was hugely great. This is more like what I’ve heard every other time changing tubes, just a little more articulate, extended, dynamic. Not life-changing. Enough to notice. Just like every other time. Including even going from 6550 to KT88.

Which, kind of a shame. If only there were more difference between tubes, then just maybe its worth hunting around for some really good ones. But the biggest difference is between old and new. Between new and new, its just not there.
Or you could go all out and get Marconi-Osram/GEC/Genelex/Gold Lion(original) KT88s. I have a pair not in use. When I did use them, my awesome but flawed Michaelson & Austin Tim DeParavicini TVA1 amp destroyed 2 of them. But when I had the quad running, they were sublime. Bass was a little ragged but the mids and highs were sweet and utterly three dimensional with infinite detail. Always tempted to build/buy a SET and use the last pair.
I doubt that there are many good OS tubes on the market. the good stuff has been picked over, sold, picked over, resold, etc., ad infinitum, and most certainly the shadiest crap is on eBay. So, don’t waste your money on OS tubes unless you met the seller at your Unitarian church, and have known him for at least twenty years.
Well, whatever those OS tubes had going for them it wasn't magic. It could only have been manufacturing. Which is all known. Like the amps themselves, it is all right there out in the open. So you do like EAT did and copy the you know what out of it. Or, like the TubeStore, you get a tube maker to copy and tweak, tweak and copy, until you get the best version you can come up with. Which is what they did with the Preferred Series tubes I just put in there.

So I have zero interest in expending any energy whatsoever looking for NOS tubes of any stripe or vintage. It is at this point simply way too hard to believe the stories are anything beyond what can be accounted for by ordinary every day run of the mill nostalgia. Those were the days, etc. 

The only ones I would even be curious to try are the EAT set, because unlike all the rest they seem to be made with actual quality manufacturing materials and attention to detail. Which, let's face it, as much stuff as we've screwed and as many times as we fall short we can at least say for sure we're able to manufacture stuff at a much higher level now than 100 years ago- when we can be bothered to go to the trouble. Which the EAT guys seem maybe to have done.

So if you got em, roll em. Roll em right on over this way. Because, Unitarian, Baptist or whatever, at $1800 a set that is the only way yours truly gonna be bothered. 
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I've enjoyed many new tubes including Gold Lion KT88s, 77s, Tung Sol KT120s,150s, 6550s, and my new fave the 7581a. All new, all great tubes. For preamp or driver tubes NOS Mullards, Sylvanias, GE...all plentiful and often not too expensive, and the new Tung Sol 6SN7GTBs aren't too shabby. I'm a fan of thetubestore and have bought lots of stuff from them...also Viva is a cool little company.
Tubes are easy. The transformer I think is what makes the biggest difference. If only it were as easy to swap those out....
I saw the ETA and maybe it's good. The GEC are magic. Not my fault if market forces drive their prices into the clouds.
Some great new tubes. Psvane 6SN7 Globe is excellent once burned in. Shuguang 12AX7LS black are better than OS Telefunkens, and Tung Sol 7581A best my RCA black plate 6L6. Have you tried the KT150 in place of your 88s?
No, and not much interested. Thing is, of all the tubes I've tried, its not that there aren't difference but rather what differences there are simply are not enough for me to care. And I am a guy who cares about really small things. The only one I recall being worth it was 6550 to KT88, where I prefer KT88. But even then its pretty small.

In contrast to that is the difference between two very similar amps running the same tubes. In those cases I have to think its almost all down to the transformers. I've swapped caps, resistors, diodes, wire, pretty much everything but transformers. And circuit topography, I'm nowhere near being able to evaluate that. But from what I do know it sure seems transformers are the real key to glorious tube amp sound.

The main problem I think is no one can roll transformers. I even keep my old Aronov amp around mostly because I keep thinking its transformers are largely to credit for its superb range and depth and I might one day have time to learn enough about electronics to restore and rebuild it. 
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It's possible my 50s Chicago transformers are so good, I can hear the subtleties of the differences between all those old tubes! 
Chicago Standard Transformer Company.
#32004. I don't honestly know how they compare to modern Lundahl, Tango or Hashimoto iron, but they give bags of detail.

The two tube amps I have the most experience with are the Aronov LS960I and Melody 880. Both are about 50-60 Wpc. Have run a lot of KT88s in both, and 6550 as well in the Aronov which can run both. Have opened up and modded both amps, most extensively the Aronov with all upgraded caps and diodes. As I've said before its easy to hear the different tubes, but the differences between them - even between 6550 and KT88 - are pretty minor.

The differences between the overall sound of the two is a different story. They both have about the same extension in terms of low to high response. But the Aronov has more authority and control down low, more midrange natural unforced presence, a little more liquid top end, and the whole presentation just has greater depth and width with a greater sense of the natural acoustic venue, if that was captured on the recording. It all adds up to a much more significant difference between the two than anything I've ever heard from any tube or cap or diode change.

Just to look at them, to judge by component quality, quality of point to point wiring, simplicity of design, etc if I had to guess based on that without listening I would have to give the edge to the Melody. Listening however its the other way around. The one unaccounted for variable being the transformers.

It sure seems to me that by the process of elimination that is all we have left. Transformers are a big underrated and unsung factor in tube amp performance.

I'm impressed you know what are in yours. I have no idea what are in either of mine. One thing I do know, sure would like to be able to build an amp around those Aronov transformers.