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Sovtek KT88

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Yeah I know, but nothing about Sovtek KT88.. and more interesting nothing on Google.. and anybody talks about the consistency and great power handling. I dont know where they get that info..?.

Anyway I want to build a SE KT88 guitar amp. Which do you suggest would handle most plate dissipation?

Thanks,

Miha
 
I have tested a few different KT88's in SE at what could be called "excessive" dissipation. The EH KT88's that have the additional heat radiating fins welded to the plates can handle 45 to 50 watts or more without glowing. Some Sovteks may have these fins but the pair that I have do not. These should be kept to 40 to 45 watts. The EH tubes seem to be the best in the overdissipation department.
 
Hi everybody,

I have 4 of those Sovtek KT 88 in an OddWatt DIY amp and I love them, great sounding tubes. Well, in my circuit, SIPP, one of the grids is layed to ground, and not all tubes like their grid to ground. The EH KT88 won't stay balanced in my amp, the Sovteks do stay balanced perfectly. This amplifier is the best I ever heard, so if you have interest, drop me a pm.

Kind regards from Holland


Ben
 

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Sovtek KT88 data sheet

Hi Gregory, (I hope this is your name:)),

looking at my Sovtek KT88 closely, they look very much exactly like those made by JJ (or Tesla, the same thing) I am not certain, but maybe New Sensor buys those at the Tesla plant. This factory is Czech. But most tubes New Sensor sells under the brand name Sovtek are made in Russia at Reflector Corp in Saratov. So that is where the KT88 could originate from, too. Nonetheless, I cannot supply you with a spec sheet either. Here is what I found:





Reflector Corp, Saratov

Reflector makes most of the tubes marketed by New Sensor Co. of New York under their "Sovtek" and "Electro-Harmonix" brand names. Some are old Russian tubes, others are made especially for export. They recently acquired the Tung-Sol, Mullard and Genalex trademarks and are making replicas of famous audio tubes from these long out-of-business companies. Types in production:

12AX7EH, 12AX7LP, 12AX7LPS, 12AX7WXT+, 5751, 7027, EL34WXT, 6550WE, 6550WD, KT88, 6L6WXT+,

5881, 6922, 6EU7, 7199, EF86, EL84, 300B, 2A3, 6A3, 6B4G, 6072A, 6973, 7868, 7591A, 7591XYZ, KT66, KT88,

5AR4, and many others. Also variants of above bearing "EH" suffix. "Sovtek" also markets 5U4G,

5Y3GT, 6SN7, 6SL7, 6N1P, two 12AX7s (WA and WB) and a few other types made at other Russian factories, primarily Voskhod Kaluga.

Note: there is no "Sovtek" factory. "Sovtek" is only an American brand name owned by New Sensor.

(New Sensor currently owns the Svetlana "S" trademark name and logo in the USA, and is attaching this logo to Reflector-made tubes.) (Note: There was a factory in Kaluga called Voskhod Kaluga. They once made 6V6s and 12AX7s for New Sensor. Their continued production cannot be confirmed at this time.)

The only funny thing is, according to that, Reflector makes KT88 under the Sovtek brand name and under the Electro Harmonix brand name as well, but those two tubes are very different, the Sovtek KT88 is maybe the best KT88 there is right now, but the Electro Harmonix don't stay ballanced in my amp.


Best regards from Holland


Ben
 
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Reflektor Corp. in Saratov is now known as Expo-Pul and is a wholly owned subsidiary of New Sensor Corp. Just wanted to set the record straight.

New Sensor does not publish data sheets for any of their tubes, generally they are considered to be electrically equivalent to the historic types they are modelled after. This more or less works in most cases with the occasional exception that plate dissipation isn't always consistent with the original.

Sovtek, EH, Genalex, Mullard, and Tungsol branded tubes are all manufactured in this plant. (Some "Svetlana" types are also manufactured here, but should not be confused with the products of Svetlana SpB in St. Petersburg now sold under the "Winged C" moniker.)

Note however that I have some GE and Sylvania 6BQ5 (NOS) that also do not seem to be as rugged as most of their cousins and exhibit plate glow under conditions where other brands function quite adequately.
 
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