Don, go here:
http://www.jacmusic.com/
and click on tubes > kt88, for a very interesting history and survey of all kt88 tubes, new and old. Neil . |
Don, my new McIntosh MC 275 Mk IV came with Russian Svetlana "S" KT88's (branded 'McIntosh', but that's what they are) and they sound wonderful, 'course I haven't heard anything else (yet) but I've no complaints. Mac also uses Electro Harmonix KT88's I understand. Those two along with JJ's tubes (the former Tesla) seem to be the most popular and reliable. |
Don, I have no experience with the Tungsol 6550s but a lot of experience with Sovtek and Svetlana Winged "C" 6550s in my ARC M300 MkII amps (the "C"s were excellent, Sovteks suck ;--) Here's my take: ARC amps, although they will work with KT88s, were designed around 6550s. In addition, ARC amps are not characteristically "tooby" sounding - not hard like some SS but still very neutral. My point is that changing to KT88s would give you a little more poop (bass control) but probably not warm things up that much.
With regard to the McIntosh amp I use now (and though I haven't tried this myself) those who've tried both report that the KT88s have more sparkle and slam than the 6550s, so go figure!
If you haven't had or done (it's easy) the capacitor upgrade on your VT-130, you should. The parts are only $200 from ARC and that would be a genuine improvement to an already great amp. If you want to try KT88s go ahead, but you may not hear that much difference. . |
Don, BTW, if you do want to try KT88's in the VT130, DEFINITELY call ARC first and check to see if it's OK. There may be certain precautions, or restrictions depending on the model of ARC amp you have. Ask to speak with Chris Ossanna in service. He knows everything by heart ;--) If you want to stick with 6550's and want to try something other than Tungsols, I can definitely recommend the Svetlana Winged "C". (Try www.conusaudio.com for best price and great matching.) I have also heard good rumors about the new Electro Harmonix 6550's. . |
Fred, I was just curious: where did you buy those GL's?
As I said, I've not had a chance to compare the GL's w/ the Penta KT88SC's (it's about 50/50 which one people like better) but I've never heard of reliability problems with the Pentas. You might want to give them a try the next time. . . . . . . and they're a little less money too! |
For Pentas (and GL's too) I think Doug at http://www.dougstubes.com does a great job w/ matching and general QC. His prices are very reasonable (I remember thinking his shipping charges were sane as well :-) Unlike some tube sellers whom I won't mention, he doesnt pretend to know what you (or your equipment) require. On the other hand, he'll warn you away from danger ;-) So call him if you have detailed questions -- just don't ask him what you'll like! |
Any tube can go bad any time -- this is not hot news. However, vacuum tubes were once the ONLY electronic valve available -- and for the most part delivered service with the same reliability as transistors -- and, believe it or not, often the same longevity.
Of the modern manufacture power tubes, the reissue Gold Lions, Pentas (Shuguang) and S.E.D. (formerly Svetlana) KT88's all provide remarkable levels of sonic performance, though still short of the best vintage tubes. In terms of reliability, only the Electro Harmonix seemed to have continuing problems. McIntosh recently dropped them in favor of the S.E.D for their OEM KT88.
Of the current manufacture KT88's, only two have the air and sparkle of the vintage Genalex/GEC KT88's from the UK ($800 -- $1400/quad): the E.A.T.'s ($1600/quad) and the new Shuguang Treasure Series Premium Grade ($350/quad -- $650/quad depending who you buy them from). I've not heard the E.A.T.'s but I have the Shuguangs and they equal my NOS Gold Lions sonically. Now let's see how long they last ;--) . |
Hey everyone. This thread is now 4.5 years old, and so I thought I'd throw in my 2 cents concerning many of the earlier concerns/experiences people had with the available offerings back then. I still stand by my results/conclusions as reported in my last post on 4/7/10. And my Shuguang Black Treasures have been running reliably 8 hours/day +/-- for the last 18 months. From time to time, I swap them out with my (very strong testing) NOS Gold Lions just to see if the Shuggies are holding their own sonically, and they are. It's so easy to overlook deteriorating performance in many parts of an audio system (just with normal use) when nothing actually blows up! Not just tubes, but TT bearing lubrication, dirty connections, etc. However, the Black Treasures (still $360/quad premium, shipped from China) sound just the same today, against the vintage Gold Lions ($800--$1400/quad used,) as they did right after their 300 hour burn-in.
If they are still the same after another six months, I may just go ahead and sell my two remaining quads of GEC KT88's, buy a spare quad of Shuggie Blacks, and spend the extra $1500 on some new vinyl! (You can't spin tubes!) . |
Tubesrule, I sold my Shuggies to a friend (as a backup set) shortly after my last post. They were still performing perfectly, but I was antsy to try the Psvane black-coated tubes which had just come out.
The Psvanes had better quality construction in a number of areas (heavier bottle, ceramic base, etc.) but were essentially the same sonically as the Shuggies. They are still in my amp three years later and sound very nice. And just to make sure, I occasionally A-B them with my 'reference' set of vintage Genelex Gold Lions. So far, no difference ;~) . |