KT88s in place of 6550 tubes?

Discussion in 'Amps and Cabs [BG]' started by chbecker, Dec 29, 2002.

  1. I recently purchased an Aguilar DB359 Tube amp. I have heard good things about the Electro-Harmonix KT-88 tubes. Does any body know if the DB359 will except KT88s instead of the 6550 tubes?

    AMJBASS Supporting Member

    Jan 8, 2002
    Ontario, Canada
    The KT88 is a great tube, but you may have trouble fitting them in the Aguilar DB359. They are larger than a 6550.
  3. CaracasBass


    Jun 16, 2001
    Madrid, Spain
    I thought this was a Star Wars Bounty hunter thread!!!!!

    :rolleyes: :cool:
  4. Well, I email aguilar and they said the KT88s would be to fat to fit. Oh well. Can anyone recommend a very crisp/clear sounding 6550? I have heard Valve Art makes some tight stuff.
  5. bassboat


    Sep 27, 2001
    hmmm..... the Svetlana 6550C is what's stock with the DB 359. It's pretty much the most "hi-fi" 6550 out.
    New Sensor (Electro-Harmonix) has 6550's with more midrange. Some people say to avoid chinese 6550's. Don't get GE 6550's from the early 90's (labeled from a plant in Kentucky).Overpriced and failure prone.
    Military GE 6550's from the 80's are smooth sounding and full-range. Very sturdy.
    Don't know about any others, but there may be more out there.
  6. coyoteboy

    coyoteboy easy there, Ned Supporting Member

    Mar 29, 2000
    Sactomato, CA
    The JJ/Tesla KT88's fit fine in my DB728, but indeed, there is probably more room.
  7. Fat Willy in Denver did a retube for me a couple of years back. I had my Trace V6 retubed with Sovtek 6550s in place of the original KT88s and have been really happy with the sound. It was cheaper too! Is there a good reason to use KT88s?:confused:
  8. No good reason other then I want to re-tube and the KT88EH tubes seem to fit the bill for the tone I am looking for (according to what I have read anyway).

    I am happy to use 6550 if that is what I have to do. There are GT6550's in there now. I have heard they have a higher rate of failure so that was my motivation to re-tube.

    Maybe the 6550's by ElectroHarmonix might be worth a shot. Any thoughts or opinions?
  9. I really like the Sovtek 6550WE's nice midrange and not too expensive. I think that the Electro Harmonix come from the same factory but I could be wrong. I also have a set of the MPD 6550A's made in Owensboro, KY. in my svt sound good to me. Came from Watford valves in England so they should be well screened but I did pay way too much for them. They also glow blue which may suggest a weaker vacuum. Psycho Bass Guy, what is your favorite 6550 in the SVT?
  10. Had an email with Ned over at triodeel.com and got the measurements of the sovtek KT88. I think they will fit in my DB359 with out any problem.

    If I put the KT88s in my power section, would I still bais to the same voltage as the 6550s?
  11. When you say "more voltage tolerant" does this mean more tolerant of bias voltage imbalances?