Genalex - Gold Lion KT66

10 Reviews
Out of Stock
USD $‎61.95
From our reviews ... "At low to moderate volumes you get a big open sound across the guitar spectrum. Very articulate with little compression, excellent touch response and dynamics."

The Gold Lion KT66 tube is a reissue tube that is made in Russia. From the manufacturer, "Exact copy of the original clear glass KT66. The tube that created "The Bluesbreaker Tone". Used in 50's - 60's hi-fi favorites such as the Heathkit W-5M and many Leak amplifiers."

Other Genalex - Gold Lion tubesKT66 Tube Types

Additional Information and Downloads

KT66 Tube Review

Tube Matching Information:
Power Tube Matching FAQ
Perfect Pair System

Genalex - Gold Lion KT66 Datasheet (PDF)

Download Adobe Acrobat PDF reader

Warranty Information and Return Policy

Warranty Period: 3 months

All our tubes are guaranteed for 3 months from the date of purchase. (Any exceptions will be noted on that tube's Warranty tab)

If you receive a tube that does not perform to the manufacturer's specifications, please do the following:

- contact us to get a return authorization
- return it via regular mail within 90 days from when we shipped it, and we will provide an exchange or refund of the full purchase price of the tube.

Returns not related to warranty or defect will be considered at our discretion, and are subject to a 15% restocking fee.

We can not accept returns that don't have an authorization, are past 3 month, or are returned improperly.

These guidelines may be updated without notice.

Ratings & Reviews

10 reviews

Simply The Best


I have tried over a dozen different new production and NOS KT66 tubes for my JTM45 I must say after trying these I will purchase no others, The are by a long mile the best offerings at any price available. And I include the NOS Genelux at about $300 Each. They are consistent, long lasting and will give you everything from chainsaw buzz to haunting Cello like swells to Piano like bell tone chime. These things sound HUGE. Try them once and you will never go back.

Top of the pops


The builder of Satellite Amps agrees with what you state Gene.

He got my attention when he said these are the best on the current market.

Had one fail


I purchased a matched set of KT66's for my customized Bluesbreaker reissue and they sounded amazing. However, one of them went out with less than 20 hours of playing time. I just ordered a replacement. I don't want to change brands, since these sounded the best.



Changed the texture of my Low Dynamic Range on my Marshall 2266C in a sec. Should have done it as soon as I got the amp. Now I got Classic Marshall Roar on both ranges.

In my Quad II Classic Integrated Audio Amp


Replaced the original Tung Sols in my Quad II audio amp. Huge improvement in soundstage. I''ll be using these from now on.