Harp King KT88
Hi Skip,
I have a HarpKing 4X10 since 2003. Its been gigged generally twice a week with no issues. I have been using matched Svetlana KT88s as power tubes. I live in Europe and now cannot get Svetlana KT88s from my usual suppliers. I was wondering if you could recommend an alternative KT88 for the Harpking. Also could 6L6s be substituted for the KT88s without two much effort.
Hi Skip,
Many thanks for your reply. I figured that 6L6s would be a no go. My current svetlana KT88s are very good I replaced them recently after about 4 years. They do last - only now I have no spares. if I can't get the Svetlanas I was thinking of getting the Gold Lion KT88 Genalex reissue which I can get easily enough without importing from the US.
Any thoughts?
I like both your comments about Rick Estrin. I won' t change the kt88s unless I have to.I understand Rick uses the 6X10 monster. My old back couldnt handle that big one. I'm happy with my 4X10.
Hello John- I'd go with the Winged C tubes. I can't imagine that they aren't available worldwide.
I don't have any real knowledge on how the re-issue Gold Lions would be in your amp. You could check hi-fi related forums for info on how those tubes hold up in (very) high-voltage amps.
I spoke with a real guru - Earl Yarrow of Newman, California on the subject, and he suggested actual KT-90s or the Winged C KT-88, both of which are available wordwide.
Electro-Harmonix has re-issued the KT90, here is where you could order it: http://www.thetubestore.com/Tubes/KT88-Tube-Types/Electro-Harmonix-KT90EH. Winged-C is no longer making tubes, this is why prices for example on the 6550's have gone out of sight. The Harp King is a fixed bias amp, so if you change the power tubes then the bias would have to be checked for best performance.
Thanks Skip and Dale for your input - very much appreciated. I have been using Svetlana - Winged C tubes for the past ten years but I have run out of spares. Dale I note your valuable comment on checking the bias if I choose a different tube manufacturer - again many thanks.
Hello John- Thanks for writing. First let me say upfront that I am not the guru on HarpKings...... I've only seen a few. John Kinder is obviously a genius, and if Estrin loves it, then it must be good! However, as a repairman I really wish that he hadn't tried to get so much power with only two power tubes. Word is that the (hard to find) KT-90 is still the best tube for those babys, but if I were you I would stick with the Svetlana KT-88.
I'd say no 6L6s.
And hey! You must be an oldtimer like me. You can get any tube in Europe that I can get here in the US. Try
www.tubesandmore.com or eBay. International Priority Mail is affordable.
Lastly, don't change the power tubes "just because". Unless the amp sounds weak or bad let 'em run. Estrin had the same set for several years.