Favorite Power Tube?

Raylinds,

Yes, I like the triodes you listed, particularly the 45, but, I thought this was a survey limited to tetrode/pentodes, given what was listed for voting. If we want to expand this to some really crazy exotics, I have heard a terrific amp that uses a meshplate 252. That is a CRAZY rare tube. Pairs of the MUCH more common regular 252 go for $20,000 or more for used tubes (probably no such thing as new old stock), and there is no price for meshplates because they are pretty much never on the market. A dealer in the Washington DC area, Deja Vu Audio, has a single amp with that tube in it.

 

I've only had EL34 amps, and have grown fond of the East German made version of that tube disappeared around the time the Berlin Wall got pulled down. I've developed an interest in tube history, and have been building up a NOS stash of many of the tubes listed above (EL34/6L6GC/5881/7591/7868/a particularly nice gouping of EL84s) - if you're considering rolling some tubes, feel free to PM me if you're looking for something in particular.

 

With a disclaimer that the tube in question is matched with a speaker system that complements the amplifier circuit topology and its power output favorably within my listening space -- both electrically and to my ear -- I'll rate my output tube preferences in the following order:

Single-ended amplifiers:

1) tie between 45 and 801A
2) 845
3) 300B but in a specific amp -- my amps -- based on a "Legacy" circuit as designed by Thorsten Loesch. Quite a bit different-sounding from the sound that 300B is commonly stereotyped for. Outside of that, I'd rank the 300B in a well-done WE91-style circuit AFTER a good 2A3 SE implementation.
4) 2A3

Push-pull: tough choice, these can all be so damn good; all a matter of system matching.
1) 7591, though my experience with this tube is limited to an old Fisher that was not restored at the time I had it, and the fully restored MC225. The MC225 in its fully restored form is just killer and, IMO, transcends the notion of vintage vs. modern performance: its just a fantastic amp that is not easy to rival in this power range. Even blurs the line between SET vs. pushpull with an efficient speaker.
2) 6L6. Again, spoiled by the glorious sound from restored MC30s. Had two other amps in the past with 6L6s (one quicksilver monos modified for 6L6 and one custom build) and also enjoyed them, too.
3) tossup between EL34 and EL84. Love both! Someone said "I never met an EL84 amp I didn't like" and I'd echo that. I also haven't really met an EL34 amp that I hated personally. Something as simple as the good old ST-70 or ST-35 in good condition, can provide just a wonderful musical experience with the right speaker, let alone some other well-regarded designs with good iron.

 

My two favourite valves are not listed - the 300B that a number have mentioned. I have had a few pairs of those.

The 6C33C is what power my current SETs (with a second one used for a voltage regulator) and although not a directly heated cathode they are full of life, reasonably linear and don't require a huge V+ between anode and cathode. They are rugged and long lasting and not that expensive. This is not an uncommon output valve these days and a number of designers use them.

I have no experience with the others listed.

 

"Not that expensive" Always a good thing

 

Thanks for your reply. I have not much experience with tube swapping outside of guitar amps. But I do love the sound of my Grundig 2065 table radio with a single ended EL-84 (with planar tweeters, I think ribbons) and also a particular affection for the original 1960's Vox Cambridge Reverb with EL-84's. The current model Orange TT-15C is guitarist heaven with its 15 watt class A EL-84.

I am wondering what would happen if I try a pair of EL-84's in place of the 6v6's in an RCA push-pull hifi amp? I have a 1957 SHF-5 which works, and apparently the filter cans are still good. But I have to be looking up the bias specs on the EL-84, which should be about the same as the 6v6 I am thinking. The OEM speakers are 12 inch full range AlNiCo, curve linear paper cones with surprisingly good hi freq extension. (measured pink noise flat to 10Khz and rolling off about 5 dB at 14 Khz) I think more could be coaxed out of this console just by the addition of 3/4 inch tweeters crossing at 10k. This will be a curiosity mini-project.

 

I think you will like it. You can buy tube converters to use el84's in 6v6 sockets on ebay.

 

There are quite a bit of difference between different brand/vintages of every tube type, so that reporting a "favorite" might have to get down to that kind of detail. For example, I use el34s in my headphone amp. I have a friend with a large stash of old tubes and he brought over several quads for me to try out. One set was Mullard EL34xf2s, another quad were 6CA7s (don't recall the brand, they were 1960's vintage), another quad were Mullard EL34xf4s and the fourth quad were Telefunken EL34s. They all sounded different. I got to choose what I wanted as a gift. I took the Telefunkens, although I kind of liked the xf2s as well for a quite different sound.

 

I voted for KT66 because my dad's Heathkit used them.

 

Wow, you' ve got a friend.

 

I loved the Mullards. I remember when you could get a matched pair of NOS ones for a hundred bucks. I haven't seen a real NOS matched pair of Mullard EL34s in a few years now.

Looks like EL34 is in the lead by a bit.

 

After running EL34's in my Music Reference RM9 for the last 5 years, I put in some EH KT88's a few weeks ago. Wonderful, I'll never go back to the EL34 (at least in this amp).

 

Doel any of you KT88 guys miss the mids of the EL34? Any particular tubes you use to make the sound a little more lush?

I'm currently using a Fisher 500c with some vintage Westinghouse 7591s. I'll be replacing those, sometime next year I'm sure, with some of the new Tungsol. Love the midrange but must admit I really love that EL34 midrange. My first experience with them was a little 30wpc AMC tube integrated. I believe it was called the CV3030. Great, sweet mids. So my big dilema is picking between the Line Magnetic 211 (el34) vs the 216 (kt88). Any suggestions for NOS or New Production EL34s or KT88s that will nudge the sound in the direction of the other?

 

^^^^^^
I like the mids from the 7591's in the 500c and kx200.
The fisher sa100 sounds better to me with its 7189's/el84's than the other two with the kx200 coming in a close second.

I wish SED still made tubes. They made a wonderful kt88 and a really nice 6l6gc.

 

should someone in the market for an amp lean towards one based on power tube type?
I heard a very sweet amp that used 6L6 tubes and wonder if an amp that uses Kt120 tubes would / could have similar sound.

 

My favorite power tube is the Sovtek 5881. I have 2 of them in my BFVR

 

Those dimple top East German "telefunken" were pretty decent tubes for the money, but they have gotten priced up to stupid levels in recent years.

Worry less about tubes all things being equal, but make sure the amplifier itself is in top shape. Defective sockets, capacitors in power supply etc have ruined more tubes than anything else. Recognize that line or mains voltages varies, have a plan to allow for this. Make sure your equipment is not destroying itself. Then spend the money for good, tested NOS or used European or US tubes. They will outlast several sets of junk, so they are less expensive in the long run.

 

No easy answer beyond listening to the amps

Listen to the man...

 

You might find some of the last winged C 6550s (usually an easy swap for a KT88). KT120s with the right preamp tubes—CIFTE 12AU7s and Ei 12AX7s got pretty close, right down to the deep almost sucked out mids I used to hear with the EL34s. Changed to RCA black plate 12AX7s and the mids are right up front now. So many ways to change the sound.

 

I think this is largely true - and design dependent as well - in general I have found SET amps to sound much better than Push Pull amplifiers regardless of the tube types (and often regardless of price) - so long as the SET is competent and the speakers are sensitive enough not to push the SET beyond limit.

The Best SET I've heard (the best amplifiers I've heard) are the Gaku-Ons and Ongaku so I guess that makes me a 211 guy - but both are and always will be out of my price range. Other 211s I've heard from Melody and Wyatech and some Chinese brands aren't nearly as good and I prefer other amps in the EL84 and 2A3 and 300B range more.

Of course I have 845s in my LM 219IA and it offers big value sound but a big chunk of that sound can be attributed to the 310A and 300B dual driver stage before the 845.

Still the AN Empress monoblocks (8 watts of dual 2A3) is probably my favorite sounding power amps thus far that have an outside shot at affordability one day. $7,200 US a pair which for AN is a pretty good bargoon - of course the upper versions probably skyrocket from there.

Also like the EL84 - in both my OTO and my Antique Soundlabs headphone amp.

 

Mine is 6AS7G/6H13C Svetlana winged =C= (not listed), only because my favorite power amps is Atma-Sphere OTL MA-1 Mk3 Silver Edition mono blocks (each take 14 power tubes, so a total of 28 for stereo). They are USSR military issue cold war stock from the Ukraine and they are cheap (6.50USD each shipped).

Power tube rolling??? yeah, right.

Make LOVE (and music), NOT WAR!

 

The SED "winged C" 6550's may be a drop in replacement for the kt88, but each sounds different in the Cit.II.
The 6550 sounds a little colored to me compared to the more neutral sounding kt88 in the citation.

 

In my amp, a step in the direction of the EL34.

 

You have an LM219? That's great. I've been trying to find information about that amp. Can I ask what speakers you're using with it? Did you happen to compare it to the 218? What kind of heat does that bad boy throw? Sorry for all the questions. You're the first person I've come across that has one. Oh and did you stock up on the 310a just in case?