Opinions of Sovtek tubes

[Old Tele man]

...the 5XXX-series designation was used to distinguish MIL-SPEC tubes from the commerical and industrial tubes of the day, with many tubes simply being "on-spec" versions of their commercial / industrial counterparts, ie: 5881 = 6L6WGB and 5751 = 12AX7WA, etc.

...the real difference was that the 5XXX tubes were "tested & guaranteed" to meet specs while their commercial / industrial counterparts weren't.

[hasserl]

IMO the Sovtek EL84's sound like crap and I wouldn't advise anyone to use them. They sound horrid, just horrid. Stiff, wooden, brittle, they don't sound good when clean or when driven to distort.

Here's a write up I did a while ago on EL84 tubes: http://members.dslextreme.com/users/...Comparison.pdf Note the losers in this comparo.

I've been using the same set of 6N14N-EP tubes in my main practice and giging amp since this time and they still sound great. These tubes are priced very well, very competitive to anything else out there, including the Sovteks.

[Baxthorpe]

US tubes with numbers only are industrial type, and Special Quality - but they are not military unless they are JAN, CV, or CK marked, even if they meet the military speciication.

I agree with Hasserl that the NOS Russki tubes are better value than about anything on the market, but I suspect that some of the crunch in his tests was coming from the preamp, and the tubes he rated better were the ones that "forgave" that crunch, rather than passing it on.
It would be interesting to repeat that test, but with the pre-amp deliberately "dumbed down", perhaps with a 5751 or 12AZ7 as PI instead of a 12AX7.
Or maybe I'm just talking through the wrong orifice as usual ....

[Chuck_Farlee]

and 5751 = 12AX7WA

The 5751 is the 9-pin equivalent of the 6SL7 just as the 6CG7/6FQ7 is equivalent to the 6SN7.

[Chuck_Farlee]

I've been using the same set of 6N14N-EP tubes in my main practice and giging amp since this time and they still sound great. These tubes are priced very well, very competitive to anything else out there, including the Sovteks.

AFAIK, the Sovtek EL84M is same as the 6P14P-EV. Maybe yours are from a different factory?

[hasserl]

I agree with Hasserl that the NOS Russki tubes are better value than about anything on the market, but I suspect that some of the crunch in his tests was coming from the preamp, and the tubes he rated better were the ones that "forgave" that crunch, rather than passing it on.
It would be interesting to repeat that test, but with the pre-amp deliberately "dumbed down", perhaps with a 5751 or 12AZ7 as PI instead of a 12AX7.
Or maybe I'm just talking through the wrong orifice as usual ....

I'm sure that part of the crunch was coming from the PI, as in every amp I know of other than the 18 watt Marshall style amp with the single gain stage before the PI, the PI distorts before the power tubes do. But that's not part of the preamp. But yeah, I'm sure the PI was clipping anyway before the power tubes were. It's just the nature of the beast. The amp I used is a channel switcher with a very nice clean channel, as nice as any amp. That channel only has two gain stages, with a Bax style tone stack between them. It has a lot of headroom, and when it breaks up it breaks up first at the PI, then the power tubes. Any breakup at the preamp is minimal and comes in last. I used that channel to push the power tubes hard. Though I also used the "dirty" channel to hit the tubes with even higher voltage levels.

But, the biggest problem I had with the tubes that faired poorly in my comparison was they didn't sound good clean or dirty. The tubes that sounded good sounded good in either case. The Sovteks or the Telefunkens or Amperex tubes may have sounded okay when heard in isolation. But when compared to the others their shortcomings were readily apparent.

[Manic]

But, the biggest problem I had with the tubes that faired poorly in my comparison was they didn't sound good clean or dirty. The tubes that sounded good sounded good in either case.

Yup, thats been My finding too. Which would also include preamp tubes.