Sophia Electric Grade A Blue Glass KT88-ST Tubes Matched Pair -- Cosmetic Imperfection

Sophia Electric Grade A Blue Glass KT88-ST Tubes Matched Pair -- Cosmetic Imperfection
Sophia Electric Grade A Blue Glass KT88-ST Tubes Matched Pair -- Cosmetic Imperfection
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This is a brand new matched pair (two matched tubes). One of the tubes has a small loose piece of glass inside the glass enclosure, which will not impact its sonic performance nor its lifespan.

Warranty: 30 days

This patented Sophia Electric coke-bottle KT88-ST (long life version) tube has the most refined sounding with best high frequency extension, a cure for the dark sounding KT88 amplifiers. 

Positive Feedback Online Review: "The Sophia Coke Bottle KT88-ST's easily bested my modest collection of glass bottles. These tubes brought to my system clean and detailed high frequencies, round, dimensional, realistic midrange, and full, rich, and taut dynamic bass. This is a very coherent, highly musical tube." -- Francisco Duran

Darren Henley: "The tubes sound so good, that I find myself pulling up track after track. Addictive audio. The most remarkable part of their performance is the seemingly grain-less flow that isn’t limited to the mid-range, but extends in both directions out from center. There is such ease to the sound that I am listening more to music than the sound." -- Full Review

User Feedback:

Dear Sue and Richard:

I am writing to inform you how delighted I am with the sound of your KT-88 Coke Bottle power tubes in my VAC amplifier. I have tried many varieties of KT-88s and many are quite competitive in excellent extension and detail. What makes the Sophia stand out is their musically natural presentation. This is the result of their even and seamless response throughout the frequency spectrum, with nothing diverting my attention from the music and the artist. I highly recommend your KT88's to all audiophiles seeking a life-like natural presentation. Thank you for your wonderful products and customer service...outstanding!

Alan H.
Bradenton FL


Dear audiophile friends,

Sophia Electric tubes are my best choice after comparing with all new product tubes on market today, especially on KT88 tubes I bought. After 35 hours burning-in, they sound incredible. I also bought the 12ax7 (driver tube). They totally changed the sound of my system (new McIntosh 275 mark 6). I'm very happy with Sophia tubes.

Richard, Colorado

Just want to thank you for super service seldom seen…

Tubes in five days in my set playing and burning in, truly great.

And the early sound is so delicate and detailed, full of air I hardly can believe it is the same set of McIntosh 75 monos I have. KT88s are definitely redefined by you.


Kai, Finland