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Groove Tubes Silver Series ST-KT66-C Power Tube   

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ST-KT66-C Silver Series single tubeCountry of origin: China...Click To Read More About This Product

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ST-KT66-C Silver Series single tube

Country of origin: China

  • Groove Tubes Silver Series are tested and warranted to meet or exceed factory specifications.
  • Silver Series tubes are excellent for "normal" tube replacement applications and offer exceptional value.
  • Not recommended for the critical high gain V1 stages of high gain guitar amps, but perfect for the other less critical stages such as V2-V6 stages.

Silver Series ST-KT66-C Power Tube

  • Country of origin: China

Review Snapshot

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Groove TubesSilver Series ST-KT66-C Power Tube

(based on 1 review)

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Reviewed by 1 customer

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(2 of 2 customers found this review helpful)


Groove Tubes made a winner

By Hank one-man-band

from Sebring, Florida

About Me Experienced


  • Better than 6L6 sovetec
  • Good Quality
  • Improves Sound


    Best Uses

    • Concerts
    • Improves power great for

    Comments about Groove Tubes Silver Series ST-KT66-C Power Tube:

    My line6 1X12 40 watt Spider valve MKll just didn't have really good clean sound. It had a dull muffled sound. I thought I could tweek it out and I almost could, but it was still there. Swapped out the stock 6L6 sovtec power tubes for a pair of these KT66s and got a great vintage clean like a good fender twin or vox ac 50. Lots of headroom and power.Bright and full instead of dull. Put all of my reverbs, delays, tremolos and modulation effects at the post end of the chain. Now it sounds like a tube amp and not a digital imitation. Dirty sounds are sounding a little better, but now they have more power. The overdrives are smoother and the insane is still well insane. I have 1 GT gold series 12AX7 in preamp and one stock. Going to replace that last 12AX7 stock tube with a GT 12AY7, going for that old plexi sound on the crunch channel, which sounds much better with the KT66s. I love my southern and classic rock, with some 50's and 60's and a little country. Now I have the tone I need for my kind of music. You will not be able to put the metal cage back around the power tubes they are just to big and the KT66 have 7 pins the stock 6L6 have 6 pins, it is not a problem, just plug and play. Now I love playing the Spider MKll. Rock on and rock loud. Best and very easy mod well worth the money, will never use anything else.

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