Best EL34 tubes

Just to note, GE and the American companies, and in Europe M-O even, I think never made a true EL34s because there were patents on them. They made beam tetrodes that were similar direct substitutes, but have beam focusing plates instead of the suppressor grids in the pentodes. So KT77s and 6CA7 are physically different from EL34s even if they're electrical swaps, and some would say have different characteristic sounds -- with the beam tetrodes having a more detailed sound with more apparent extension at both frequency extremes than the EL34 which has been characterized as warmer and more mid forward. I dunno if that holds up, having never made an extensive comparison between original Euro EL34s and the GE and Sylvania etc beam tetrode 6CA7s or M-O KT77's (I wish), nor the extent to which it holds up for new production tubes. But they're definitely not identical tubes and they don't have identical distortion characteristics I think. Probably plenty of people on the board with experience with both types in Ultralinear circuits.

 

I changed the 120's for the 150's at the same time I got my new turntable, arm and cartridge so it's hard to say for sure if it was the 150's that don't really like UL or my new front end.

 

I went ahead and picked up a set of the Svetlana SED "Winged C" EL34 from Upscale.

 

You did good there Brian. Everything I've gotten from Kevin has exceeded my expectations. Upscale ain't the cheapest, nor do they have the largest selection, but what they sell is the best. Period.

I'm in the "hoarding" stage of the NOS tube rolling affliction, so I'm gonna continue to stock up on as much NOS tube-y goodness as I can afford. Like vintage vinyl, there's only so many left of any of the NOS tube types that are really valued.

A lot of mid-century "stuff" is fairly "hot" as commodities right now. That definitely includes NOS tubes.

 

Excellent tubes and not obscenely pricey. You'll dig them.

 

Svetlana SED?

SED was the branding after New Sensor bought the name "Svetlana"

It's odd that upscale are using both names on their sale. Anyway, I'm being picky again

Let us know how you like them after 50hours, the bass might sound pretty lean at first until you have the hours up.

 

I have the old =C= SED EL34, they are very good tubes and have lasted a long time.

I had a pair of reissue GL KT77, they are probably the best overall EL34 type I've heard if you want a neutral, detailed tube. But they only lasted about a year, I figure half of their rated life although I push them at max dissipation in my SET amp.

I have not tried the Mullard xf1 or 2, they are $$$ but I have both real xf3 and the later Japanese production that were the same, and they do sound the same so I think the later Japanese tubes are a good deal, also for 5AR4 rectifier tubes rather than buying $$$ Mullards.

Also have some Chinese and Sovtek tubes, they are ok but not great.

Next I want the RFTs.

Also, on EL34 amps, search google for the "hazen mod". Its a simple worthwhile mods for EL34s run in triode mode.

 

Dimple on top, slightly smaller than a Mullard, single halo getter - you can find them branded as Siemens in orange/blue boxes, National (Richardson), RFT, Mullard, Telefunken, Westinghouse, Amperex, lots of others as well - just look for the dimple top. Since RFT tubes were made in East Germany, they couldn't be directly imported into the U.S. However, there were plenty of other countries that allowed East German products to be purchased - those RFT tubes must have sold in big quantities to Euro dealers, and then resold with no country of origin printed on the glass, or just Germany - that's how they ended up here in the States. Good thing, as they were some of the last tubes built to last like valves from the Golden Age of production. When the Berlin Wall came down, RFT production seemed to disappear in the dust.

 

Dave, have I got this correct?

The cap connects grid 3 to cathode?

 

Something like that... It's been a long time since I did the mod to my amp and I didn't want to say the wrong thing. All other KT* tubes are internally connected and the EL34s are usually externally connected, but the mod replaces the direct connection with a .1 uF film cap. You can still run other similar tubes in the amp, the cap would then be bypassed by the internal connection. The GL KT77 is internally connected but still beats out most others, I do like the warm sound of the Mullards though.


Oh, I also had a pair of used old stock Tesla EL34s, they had the most body and tone of any of the EL34 types I've tried, they were really nice... Unfortunately I didn't have them too long before one tube malfunctioned.

 

Thanks Dave

Probably not a mod for myself, but always interesting looking at these things.

 

Or maybe I should have said "not for my amp"
I'm thinking it will depend on the amp circuit and build, and this will dictate if the mod is a positive.

But I'm no designer.

 

The El34 sound depends on the circuit implementation they are in to some degree.
I have tried many - I am currently using Electroharmonix EH 67CA7 (fatboy bottles, pentode, electrically can be place in el34 circuits) and they tolerate a bit more plate voltage than the standard EL34. They sound similar to the electroharmix EL34/ 6CA7 (normal profile EL34) and Sovtek EL34 but the plate structure of the EH 6CA7 'fatboy' tubes is different - more like KT88/ 6550. These tubes are dynamic , have good bass and a nice clear treble - more, solid, bigger sounding than other EL34 types I tried IMHO

Genelexx KT77 re-issues are nice and clear and more hifi sounding (smooth/ refined). Balanced tonally but don't have the heft or visceral impact of the EH6CA7 fatboy type IMHO.

Winged "C' (previously Svetlana, St Petersburg) EL34 are nice, they are warmer sounding and a tad less bright in the treble. Early versions said to be better than current production - check out watford valves in the UK or Upscale in the US - I think they had some.
The above 3 types were reliable for me - but you need to get them from a reliable provider or authorised dealer.

Golden Dragon (China) were thinner, leaner sounding but not reliable for me.

 

I do really wish someone -- New Sensor or Shuguang or JJ -- would or could make a tube like the old Mullard EL34s: with that warm, creamy center; the kind of magical, textural timbral realism; the easy to listen to high frequencies; and the ability to dissipate heat well above the 25-watt EL34 spec. But despite New Sensor marketing tubes under the Mullard brand name, or Groove Tubes marketing tubes as "reproductions" of Mullards, it hasn't come close to happening yet.

Almost all of today's EL34s and 6CA7/KT77s start red plating if 25 watts even comes in sight, the Mullards laughed at that. None of them have that creamy, tactile midrange or that easy to listen to quality (it's not like they sound rolled off at the top end, but there's not a hint of hardness to what highs are there). And many of them just sound thin, hard and bright, and flatten out the timbral differences between similar instruments. It's gotten so I've started to think about just eschewing any gear that requires EL34s. The Winged C's were at least good sounding and relatively inexpensive when they were in production so you could run 'em and replace 'em.

It's interesting to hear someone say the Matshushita tubes from the factory that Mullard set up are similar to the xF3's. I've been through a bunch of xF2 and xF1 Blackburn Mullards over the years but now every one of those tubes that I have are long in the tooth and I'm not sure I can afford to replace 'em with a new quad of the same tubes -- or if I could even find a new quad of the same tubes. Maybe I'll have to give the Matshushita's a try, though I'm not sure its so easy to find a matched quad of those anymore either.

 

Just a bit of trivia, the EL34 is very linear when triode strapped.

In the circuit I have they are strapped and no GNFB used at all, very nice like this...to my ears/tastes.

 

Probably be easier to scoop up a quad of RFTs...

 

Best EL34 I've heard - the original Dutch Philips from the 1950s. Very expensive now. But it has a clarity that I've never heard in _any_ output tube, new or old.

Genelax KT77s (not the re-issues). Again, very very expensive now - sort of a mix between the classic EL34 and the sound of an old Tung Sol 6550. I did some tube comparison for a single-ended amplifier:
http://6streetbridge.blogspot.com/2013/11/project-mult-valve-universal-pentode.html

And of course the Mullard XF2 (not the re-issues) - climbing rapidly in price since so many guitarists like the tone. Darker than the other two tubes, but that can be a good thing depending on system matching.
http://6streetbridge.blogspot.com/2014/02/tube-review-mullard-xf2-el34-pentode.html

I've had good results with the Psvane 5881s - would be curious to hear their Phillips "re-issues" or their EL34s. I've always been curious about the KT77 "re-issues" but never bought any - yet.

 

Or '70s Teslas, which I think really do sound similar to the old Mullards, but even those RFTs and Teslas are now circa $350 and up per quad, and not nearly as plentiful as they once were; and I'm not sure any of 'em could take the kind of heat the Mullards could dissipate, maybe not a concern in most amp, but in some of those old circuits it is a concern, and I'm sure it plays into the tubes' longevity. To borrow a phrase from Vice President Thomas Marshall, what this country needs is a really good $20 EL34.

 

I used to run Matshushita EL34s in an old Dynaco 70 - not quite the sound of an XF2 but I certainly liked them better than any of the new tubes I've tried - which admittedly hasn't been a lot. The Matshushita is often labeled as El Menco, or even as RCAs (even have a made in GT Britain screenprint). Top of my head here - they have a different glass top than other EL34s, like a pie cut into quarters.

 

Thoughts on National Electronics 6CA7/EL34 made in East Germany.

 

RFT production - I have a quad of those - good quality tube.

 

The Matsushitas have an "X" shaped pair of seams across the top of the glass.

 

That's a better description - woefully short of caffeine today

 

basically anything from the 50's and 60's will be great, the 70's mostly great, the 80's still had some great teslas and some decent groove tubes..........this is a good basic guideline for tube buying. I wouldn't stress about the brands since a lot of them are rebrands. Just find out the date code and use that as your buying guide....then listen to 'em and pick your favorite flavor. Whatever you don't dig, you'll ALWAYS be able to resell for as much or more than you paid, imo