GEC KT88 single-getter vs. triple-getter tubes


I recently received a Unison Research Sinfonia integrated amplifier and tried various tubes with it. As output tubes, I tried three-getter GEC KT-88 tubes which are great but I felt that they are overblown and rather fat sounding and lack air and HF extension. The stock tubes (Sovtek KT-88 marked "Unison Research") and somewhat lighter and brighter in a good sense and I thought I would keep them as output tubes, until I inserted the earlier vintage single-getter Genalex KT-88 tubes, which have more high frequency extension and transparency and don't have such excessive "bloom" I was suffering from. Has anyone had similar experience with these two varieties of GEC tubes? I will also appreciate any tips about a reliable source of NOS/NIB GEC/Genalex KT-88 tubes.
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Transl,
I have Unison Research Performance amplifier,it is same as Sinfonia beyond one Kt88 plus for each channel.
I am happy with Shuguang KT88/98 power tubes and for the 12au7 I could not find out any better than stock EH12au7s (I do not know it is because of this amps circuity or what reason?) and for the 12ax7s I have the best sound with both Ei and Shuguang 12ax7s.
I also replaced the stock icel brand capacitors (one 0.47 for each channel)with
Vcaps and made this amp much better.
Thank you, it's very interesting - about V-caps and everything. A year ago I replaced the stock 0.22uf caps in my Cary SLI-80 with V-caps and after a long, long burn-in (though their flavor was apparent at the outset) the amp opened up. Still, I believe thay are colored.
jtaysk: I don't have a tube tester. I ordered three-getter GEC tubes from HK as NOS two years ago and they appeared as such, but who can tell...

I've seen GEC tubes at Tejatubes, they also occasionally appear at Brent Jessee Recording, but the price is US$1500-1660 a quad.
Was able to compare the Shuguang made KT-88/98 (which are superior built and sounding than other KT-88 types including the so called new production Gold Lyon Russian power tubes) after 3 months or so compared them with GEKT-88 also Chinese and the improvement was a major step.
I have not tried sinlge getter KT-88 since the 88-98 has one side getter and another (halo up on top) now the GEK-T88, has 3 getter and it sounds really good.
I've found a guy selling the GEC "originals" blue sticker which reality says they are originally made in china outsourced fromm Genelex in the 1980'2 qndd 90's (SOUND FAMILIAR??) the British KT-88 GEC have been out of reality reach for the last 10 o 12 year at the every least.

Today's choices are clear, GEK-T88 from China is a steal for the price quality is very musical, organic presentation, smooth top end, bass authority etc. etc.
Sounds really good, that's what I can say, now . . mind you the little that I know about tubes is that nobody can predict how a particular tube will sound in the context of the particuloar circuit and also interaction with the other tubes in the equipment, and that is a fact.
example some people swear by Mullard small signal tubes (12AX7) now sometimes Mullard sound with no bass, no top end to speak of and no timbre distinction, is that a problem with the Mulards?? i don't think so is just the inetraction with the other tubes and the synergy of that interaction. on that application teh best sounding 12AX7 was indeed a Sylvania 12AX7 NOS that can be had on e-bay for a few bucks, Luckily I have good friend tube addicts that we exchange our tubes to see what works best with what other and the surprises are many that way . . .
Another word of advice, some of the new generation of chinese amplifiers made with tubes are really of superior quality, the problem, most of them are designed to work off 110 Volts. this country of ours hasn't had 110 Volts for at least 15 or 20 years, in my neck of the woods the norm is 123 Volts for the grid, si using a step down trasnformer or simply a Variac is a must otherwise reliability of these amps becomes a factor, since plate voltages multiply, in reality a plate voltage of 450 Volts for a KT-88 tube ends up being almost 570 volts with the extra voltage coming form the grid, that blows up anything.
Go ahead discover some of teh wonderful Chinese tube amps you see in the market doem of them based KT-88 and 300B are truly wonderful pieces, than in time maybe swap capacitors for betterquality for a top notch sounding tube amp thta couls easily rival $10 to 20,000 esoterics for under $1K, now you know it . . .
enjoy tubes they are the real music and tone of real instruments vibrating in space, somehow trnsistors no longer cut it for me, they can sound very nice but not as real, melodic or tibrally correct as the tubes.
Compare $15,000 SS amp to $1,200 tube integrated yhou'll see for yourself.
Hope it helps a little;

God Bless!

Gonzalo
Well this is the first time I saw someone saying something bad about the New Golden Loin KT88.
Pretty much any review anywhere online gives very very positive results. You will find reviews saying they are as good as the real NOS KT88 and some say even better.
All I know is I bought a Quad of them off Jim MacShane on Audio Asylum and these New Golden Loin KT88 are in a leaque of their own. No other New production tube can hold a candle to them. I replaced my Shuguang made KT-88 with the New Golden Loin KT88, the Shuguang KT-88 were good indeed, but isn't in the same leaque as the New Golden Loin KT88.

Prehaps with the other poster his diver + gain stage tubes were not a good match for the New Golden Loin KT88.
Synergy with the other tubes does have alot to do with it, along with the circut. Some amps will show more diffences than others when it come to tube rolling and this is where alot of fun can be had in fine tuneing.