6550 / KT88 / KT90

KT88's generate a lot power, handling significantly more plate voltage than other power tubes. As a result, KT88's and 6550's are produce cleaner tones and have low distortion, making it popular amongst bass amplifiers and high end audio applications.



  • Valve Art 6550

    Valve Art 6550
    $39.95
    Valve Art 6550
  • Tung-Sol KT120

    Tung-Sol KT120
    $49.95
    Tung-Sol KT-120.
  • Tung-Sol 6550

    tung-sol-6550
    $38.95
    Extended highs, sharp bottoms. Wide bodied tone. ****SINGLES ONLY****
  • Svetlana 6550C

    Svetlana 6550C
    $37.95
    Solid, reliable, lots of clean headroom.
  • Ruby KT88V-STR

    Ruby KT88V-STR
    $54.95
    Ruby KT88V-STR. Solid plate, triple getter.
  • Ruby KT88-STR

    Ruby KT88 STR
    $44.95

    Select 3-hole plate KT88 made by Shuguang in China. Also re-marketed as Valve Art.

  • Ruby 6550A-STR

    Ruby 6550 STR
    $38.95

    Ruby 6550A-STR is a Chinese Shuguang(Sino equivalent) - selected by RUBY.

  • Penta KT88SC

    penta-labs-kt88sc
    $57.95
    More refined, detailed. Good for hi-fi and guitar alike. ****OUT OF STOCK**** Please order RUBY KT88V-STR's.
  • JJ KT88

    JJ KT88
    $38.95
    Detailed character, tightly compressed bottom end.
  • Gold Lion KT88

    gold-lion-kt88
    $59.95
    Smooth tone, and great broad frequency range definition.
  • Gift Card 2017

    Gift Card 2017

    From: $25.00

    To: $100.00

    Doug's Tubes Gift Card 2017
  • Electro Harmonix KT88

    Electro-Harmonix-KT88
    $36.95
    Great tonal character for the price. In stock.
  • Ei KT90 Type II

    Ei KT90
    $99.95
    Singles available.
  • ANOS GE 6550

    NOS-6550-A
    $89.00
    ANOS GE 6550. Only unmatched singles available.

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