Besides Hammond, who makes a 25 watt OT with 4-8-16 taps?

[rooster]

Yeah, I know, I found myself mentally going over this event while eating lunch today..... I must admit at the time I was thinking in reverse of the science, but here it seems like the science actually went backwards for a moment - which is impossible. So I've decided that the Mullards were warming up even though the amp had been on for 5 minutes. ? That's all I got.

I will have to revisit this ultimately, yes, and soon if I can stop playing the amp long enough. To be honest, I am thinking at this point that I don't know much about Mullard EL34s. And, oh yeah, I thought I did. In going over things, I think it pretty safe to say that the plates stayed pretty constant while I dropped the bias 5 ma - something I don't typically expect of power tubes. But maybe the Mullards are different. ? Well, or not, a 1-3 volt swing on the plates might be typical here, what with the huge Tonesluts PT. ?

And all of this said, I am still stunned by the sound of these power tubes in this amp, and yes, biased at 30 ma. My other tubes are a Tungsram (V1), a Mullard long smooth plate (V2), and a GE (V3). You don't know me, Wayne, I realize, but I am telling you true when I say that the whole character of this circuit/amp went from 'very cool' to 'unreal' status with the Mullards. Its like having something cool and thinking you 'get it' and then finding out that it is way way more.

What I don't fully understand is why I never heard this in the Mullards before with all the amps I have over here that I have tried them in. I am starting to think that the target plate voltage of 390-400, something KF sought and Marshall used in their 50 watters for so long, is a pretty smart call. In fact, all my amps that I tried these tubes in were seeing 460-495 VDC on the plates. (Well, lets not forget KFs EXP circuit, too!) And then there's the OT. The 35 watter Toneslut/Heyboar couldn't begin to deliver the detail and crispy crunch that the amp has now, along with some volume. Like I said, its unreal, I have never even dreamed an amp could sound and feel like this. Oh, I know, I'm frickin' gushing, very sorry to do this.

Oh, I did try the Toneslut OT at 32ma with the Mullards, BTW, but I didn't get what I have now. That first amp is in a state of disrepair or I would try it again. I'm putting in my own boards so I will get this done and try it again someday soon.... Whew, long winded and sorry.

[Wayne]

Hey - as long as if floats yer boat, the rest is just numbers!

I don't have much (read: virtually none) experience with vintage tubes. They're just a little out of my price range. Hell, even new production is technically outta my range, but I do bite the bullet a couple of times a year and re-tube, for reliability's sake as much as for tone.

I have no problem believing that old tubes in good shape could sound better - "They don't build 'em like they used to" seems to apply to just about everything "they" build, or ever built. Every time a tube manufacturer comes out with a re-issue, I get excited 'til I find out that they still don't make 'em like... etc.

I am intrigued by a conversation in another thread with the west coast ham operator now living in Russia. We could probably tweak old classic designs, or make new designs that make allowances for the differences between NOS & new production tubes, at least up to a point. That's just me - always looking to save a buck or two

Anywho, I'm glad you've found tone that you like - I'm still looking, but I'm not even sure I know what I'm looking for...

W

[rooster]

Hey thanks, its a brave new world for sure. Yeah the reissue tubes... Right now I am slightly embarrased that I liked the KT77s so much. But they really sounded really good in the TW. Maybe hard to picture this but I had a friend over just yesterday and he played out of 5 of my amps, a SR, an AC30, tweed Super, LF22 (my own design), and the TW, one right after another. He runs a Matchless Chieftain, had it for about 8 years and loves it. All the amps sound very good, but the TW stopped him in has tracks - and this was with the KT77s! (I skipped the Marshall, BTW, because it sounded like shite compared to the other amps, and this was with the Mullards... )

I do think that people these days are typically overbiasing the newer tubes in hopes that they will sound a little better. Odd here too is that a lot of the newer ones sound best in Class A amps where they are naturally running hotter. For example I put a pair of the new 5881s on a Class A Magnatone 260 with P12Ns after its RCA blackplates went south. It sounded great, fantastic really, and had a great feel, as well.

Anyway, I'm really like you on not wanting to spend the $$ on NOS tubes. A right speaker choice can make a bigger difference than any tube in my book. But I will spend the $ on Mullards for this particular amp now, hearing what they do. I still almost can't believe it though. I have this one friend who plays rock style gtr with a 100 watt Plexi who had these Mullards that were just barely hanging on. Now I KNOW he is almost deaf, seriously, and he would say to me, 'Oh man, can you hear how good those Mullards sound in my amp?' No, I really couldn't, and I know he couldn't either. EVH used then on the first album for certain, with a Variac - again, lower plate voltage? - and I CAN hear that, Awesome tone. But I never had it in my hands. Hmm, and now I sing the praises of dusty old power tubes, never saw that coming, Wayne. Like I said, it took a TW.

[GrungeMan]

Doesn't Triode sell a 25watt OT with a 6600k primary and 4,8 & 16 ohms secondaries?

Grungy

[rooster]

Triode transformers? I will check that out, thanks.

BTW, to whom it may concern, I put the Mullards back to 34 ma. Where 30 ma seemed to be working pretty well yesterday, I think I was just pounding the shite out of my guitar in my excitement, making it happen. Today, with my strings not quite as snappy, and with my science hat on, I backed things up a bit and went back to 34 ma. And actually, going from 30 to 34, the plates moved 1 VDC if that. The amp just felt smoother this way, and the midrange thing is still there in spades.

Too, one other thing I have to report? I did my bright switch like some others have here, 50pf on the top position and 100pf on the bottom. Of course the stock EXP is 100pf/500pf. Well, FWIW, I find that I really can't appreciate the 50pf position with the Mullards, and end up keeping the 100pf cap on. So suddenly, with the Mullards, I really begin to see the need for the 500pf cap. Surprising news. So I will change this. And actually, I really don't like NOT using the bright switch at this point. With the KT77s, the 50pf cap was totally valid and usable. I guess this speaks about the top end of either tube - the KT77 has got more top end than the Mullard. And its true, I am now turning the Presence control up more than I did.

[Wayne]

That's the thing about tubes - did you try more than one set of '77? More than one set of Mullards? They may very well be as different from one tube to the next as they are from one brand to the next. Magic, huh?

W

[rooster]

Ah - Grasshopper returns for his beating. Where to start....

After a few days with the Mullards, XF2s, I might add, I decided to actually try 6V6s, which is what the Hammond iron is all about and something I had been avoiding. Don't ask me why I fought this for so long. I have about 6 sets of J/J 6V6s here, some RCA grey plates, and some Philips black plates. After running the lot, the J/Js stood out. The RCAs were good but they have tube shake, loose mica supports in the bottle. Hmm. The amp knobs were back to their old habits, and the bright switch, too. Similar to the KT77s, but much smoother somehow. Translation: the volume knob just seems to ramp up into overdrive in a more even way. I biased them at 26 ma, 400 plate. The distortion is better. the clean headroom is about the same as the KT77s I originally ran, and the volume is pretty similar, as well. Comparing them to the Mullards, that midrange roar is quite reduced, which I suddenly have much more appreciation for. ?? Yeah, call me fickle, but I am backing the bus up...

On the Marshall amp, actually, as well, I decided to run a pair of old Genelex KT66s, as well, and just shelve the Mullards. Now that I understand/hear what the Mullards were doing in the EXP, I am just off of them for now. In the right Marshall, a bright one, I can see where the Mullards are maybe the thing. My Marshall is more Bluesbreaker style with a fatter front end so I don't really need the extra thickness. Hmm. I did learn something about the Mullards, I guess that's mostly what's going on here.

OK, wrapping this up, I made a mistake about the Mullards in my EXP. The midrange color completely swayed me, plain to see now. Further, total retraction: I will NEVER run a set of these in my EXP again, nor seek them out for it. Alright, fool delivered in print for all to see. I am afraid to offer that I do like the J/J 6V6s very much with the Hammond 25 watt iron - for fear of a future retraction. ....