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6550 / KT88 ... pick me a set

Discussion in 'Amps and Cabs [BG]' started by James Hart, Dec 22, 2004.

  1. Electro-Harmonix KT88EH

  2. Sovtek KT88

  3. Tung-Sol 6550pad

  4. them hunderd watters from Walmart for a buck 77 per 4 pack

  1. James Hart

    James Hart

    Feb 1, 2002
    Endorsing Artist: see profile
    OK, I'm going to be as vague and as pointless as I can. I've read, I've asked, I've tire kicked.

    Money is coming and I need to order a set of 8 power tubes to live a long long well tuned life in my Peavey.

    Which should I get and why :bassist:

    Electro Harmonix KT88 @ $200 for 8

    Sovtek KT88 @ $200 for 8

    Tung-Sol 6550A @ $280 for 8

    all 3 types are made in the same plant and distributed by New Sensor.
  2. James Hart

    James Hart

    Feb 1, 2002
    Endorsing Artist: see profile
  3. lame(B)ass


    Jun 18, 2004
  4. James Hart

    James Hart

    Feb 1, 2002
    Endorsing Artist: see profile
    nope... I like JJ stuff (got a couple 12ax7 going in it), but I'm not considering their KT88 for this head. That is what was in it last and wasn't a good match.
  5. CrackBass


    Aug 10, 2004
    you might consider sveltlanna. i believe they make some great 6550's. and i don't think they are too expensive either.
    haven't used them but read great things about them. i have tried their el-34's and they were really good.
  6. BassGreaser


    Aug 22, 2002
    Austin, TX
  7. Joe P

    Joe P

    Jul 15, 2004
    Milwaukee, WI
    I don't know about the brands, but what I do know is that the 6550 was designed as an 'industrial' tube (presumably high reliability?), and the KT88s are what they use in audiophile stereo gear - and as far as I know the KT88 is very similar to a 6L6 (maybe the same, but stricter Q. control?).

    I also remember hearing somewhere that Metal guitarists are known to switch-out their 6L6s for 6550s, because the 6550s have a distortion sound that's different - better for metal.

  8. James Hart

    James Hart

    Feb 1, 2002
    Endorsing Artist: see profile
    I've narrowed my choices to the 3 listed, no others are being considered for this head... they all have the least negative / most positive reviews from the techs and players I've been bugging in regards to tone, consistancy, reliability, etc.

    Hey Greaser, you could poke holes in those winged C tubes and the Hexa would still have killer tone :smug: I've got a V4 sitting unused locally that hopefully will be mine one day (that will most likely get some JJ power tubes)

    thanks for the posts and votes
  9. lame(B)ass


    Jun 18, 2004

    Hmm....did you tried asking at official Peavey forums? I used to lurk there few years ago and there were plenty of nice and helpful folks who knowed their stuff. There's chance that you can find another Classic 400 owners there. Just a thought. :)
  10. Thornton Davis

    Thornton Davis Supporting Member

    Dec 11, 1999
    I put 8 new Sovtek 6550WE power tubes in my Peavey Classic 400 five years ago.

    I haven't regreted it for one second. You won't either.

    Just make sure you buy matched pairs and have your amp technician re-bias it. Have him set the bias so the tubes run cool, not hot.

  11. 6550's and KT88's are basically the same. They are NOT the same as 6L6's.

    The pins are the same, but they're NOT interchangeable. The 6550's have much higher heater (filament) current draw as well as other very different characteristics. Only a very few amps can accept 6550's in place of the 6L6 family---early Ampeg V4's for example use a 7027, which is in reality a 6L6..but even then the amp must be rebiased.
  12. James Hart

    James Hart

    Feb 1, 2002
    Endorsing Artist: see profile
    Thanks guys.

    Yes, I've posted at the Peavey forums in the past... never thrilled with the kind of responses I got. I'm pretty confident in these 3, and will most likely go with the Sovtek KT88. It has been praised slightly higher with most I've spoken too... but they other 2 are close.

    Thornton, I've lucked out with my tech. Not only is he busy and respected in the area... he's authorized Peavey repair too. He has had a couple Classic 400 heads through his door. I should have mine to him the first week of January :bassist:
  13. mgmadian


    Feb 4, 2002
    Austin, TX
    I'm in a similar position, need to find a sextet of KT88s for my Trace Elliot V6 (a couple tubes busted in shipping). I'll likely go with Sovteks, mainly based on (i) word-of-mouth describes them as rugged and sounding 'good', (ii) I spoke with the former Service Mgr at Trace, who mentioned that Trace mostly used Sovteks in these amps, and (iii) they're a little less $$ compared to others (e.g. JJs).

    (ii) wouldn't apply to you (though it would if you pick up that V4), but I'll vote for Sovteks on the basis of (i) and (iii)...sorry, don't have any first-hand experience myself. Couple of questions:

    1. any idea if it's possible to pick up a matched sextet of these things somewhere? or does it it matter...matched pairs are good enough, and the amp tech can set the bias appropriately with the pairs?

    2. Any other recommended retailers? ... wondering if it's possible to find 'em for less than $50/pair.
  14. Two trios are what you'd need and are actually harder to find than just getting a matched sextet since they'd need to be close and NOBODY matches odd numbers of tubes unless you specifically request it.
  15. James Hart

    James Hart

    Feb 1, 2002
    Endorsing Artist: see profile
    Thanks Everyone. I'd researched this a bit and had mostly made my choice before the thread... cold feet made me post it :bassist:

    I've got 2x JAN and a JJ 12AX7 in the preamp section. Then a EH 12AX7 as the input stage and phase splitter with an EH 12AT7 as the driver.

    I'm ordering the Sovtek KT88 this weekend... Tech gave me a < 2 week turn around on the tune up & bias once I get the tubes in hand.

  16. amper


    Dec 4, 2002
    Can you explain this "two trios" thing? That doesn't seem to make any sense to me...a Trace Elliot V6 (or any other TE V-Type) is a fixed-bias push-pull Class AB amp, and as far as I am aware, the V6 must have a matched sextet.

    I recently emailed GT asking for rec's for tubes for my original V-Type, and Myles Rose suggested the GT KT88SV in a #4 or #5 rating. GT charges $75/ea for both versions of the KT88 that they offer. Their site only lists singles, duets, and quartets, but I'm sure they could come up with a sextet (or even an octet, if you have a V8) if you asked for it. Of course, six of those would run $450.00, but IMO, the V-Type series is worth it!

    I'm still running my original TE tubes, and have been for years. They sound fine to me. On the other hand, I have an emergency backup quartet of KT88's that were pulls from a VHT amp that I paid $50 for on eBay.
  17. James Hart

    James Hart

    Feb 1, 2002
    Endorsing Artist: see profile
    GT as in Groove Tubes?

    What manufactures tubes are they relabeling for you @ $450 a matched sextet?

    I just ordered a matched Octet of Sovtek KT88 from for $200

    for $450 you could score a matched sextet of NOS GE 6550 or some other holy grail tube.
  18. Amper, the Sovtek KT88s mentioned above by James Hart are the finest current-production tubes available for your Trace Elliot amp, and cost much less than the inferior GT ones that you've mentioned. You won't be sorry.

    I have a V8, and I can guarantee you that I will never put GT in there!
  19. Like you said, push/pull, each half of the sextet is a trio and with dual bias controls, you can bias them differently to adjust for variation in emission. They'd have to be reasonably close trios but they wouldn't have to be "matched."
  20. amper


    Dec 4, 2002
    Ah, I see what you mean. I wasn't thinking of them in the same way.