KT66's or 5881's?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by retro, Jan 26, 2006.

  1. retro

    retro Member

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    I am looking at non NOS, KT66's or 5881's for a JTM45 RI.

    Anyone have an idea of how the new production Tung_Sol 5881's would compare tonally and headroom wise to something like GT HP's or Valve Art's KT66's. I'm looking for good tone of course, but would like to keep as much clean headroom as possible, if possible. Not sure what would be the better choice with that criteria to try first.

    If it matters, the Beano tone is not a factor for me.

    T.I.A.
     
  2. Matt H

    Matt H Guest

    the valve arts kt66 is a very fine sounding tube... i'd imagine it'd have more available clean headroom than a remotely "Accurate" 5881.
     
  3. retro

    retro Member

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    Thanks Matt...
     
  4. wgs1230

    wgs1230 Fully Intonatable Silver Supporting Member

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    Neither. The SED 6L6GCs are more efficient and have higher headroom than either. And if you can spring for NOS, 7581As are tops in the headroom dept.
     
  5. VintageJon

    VintageJon Member

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    Well, I have to go with wgs1230 here, EXCEPT the Ruby 6L6GCMSTR has proven to be very good here.

    I would not think a real KT66 and a real 5881 are comparable as each is based on a different design. The KT66 is a large bottle Euro 6L6GC while the 5881 is a small bottle 6L6GB. The 5881 won't take what the KT66 will
    in either plate voltage or IPD.
    (HUH? You'll get more headroom with a KT66 or 6L6GC...)

    -Jon
     
  6. retro

    retro Member

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    Thanks for the info and recommendations.

    Originally I was just going to look for NOS GEC's. But decided to take another path towards headroom with cream on top.

    Glad I did. I am starting to learn some things...thanks again.
     
  7. fjs1962

    fjs1962 Silver Supporting Member

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    It's interesting that this would come up as I was just talking to Greg Germino yesterday and he told me he's had to start putting 6L6s in his Classic 45 head (JTM45 type) because he's had such bad luck with the current production KT66s. He said he's talked to a couple of other builders who said the same thing. Greg said he's using the TAD short bottle 6L6s and they sound great in that circuit, and also that he's heard nothing but good things about the Tungsol 5881 reissue although he hasn't tried them yet.
     
  8. slider313

    slider313 Silver Supporting Member

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    I use JJ6L6's which have great clean headroom,tight bass,and smooth top end.I noticed Groove Tubes is using JJ6L6's now and labeling them 6L6/KT66/5881.They use a numbering system(1-10) to grade the tubes for clean headroom.I personally buy from www.eurotubes.com Tell Bob at euro what amp and tone your going for and he'll be glad to help you.
     

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