These sound way better than any EL34 IMO
Genalex Gold Lion KT77 Power Tubes
They are worth the money and are a sub for EL34
but BETTER !!
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It’s obvious you don’t own Cary/AES Six Pac, Cary V12, V12Rs, Marantz 5,7,or 9s, I DO!
The Six Pacs I own came with two brand new sets of matched GL KT-77 Sixtets. They did a super hot rodded AES 6 Pac, NO JUSTICE, they just sounded BAD. Swapped over to a set of Rubys, brighten right up.
I tried them in a V12R, for a couple of days, friggin’ valve failed. Started losing the health light on the V12R. I pulled all 6 on one side and put Rubys in, LOL THAT was an eye opener.. Night and Day difference, left and right speaker, GL vs Ruby, no contest..
That valve in ANY of the above amps won’t hold a candle to either EH or Ruby plane and simple. This is from an owner, not a guy trying to sell valves, or reading articles, someone else published. Hands on, OWNER. The only valves that are as good or maybe a tad better is old stock Mullard,Volvo, or Tellies.
American made 6CA7, sylvies, are a MUCH better valve if you can find 6 that match at a time.
KT77 GL new stock is russian made, 10% tolerance and have a high failure rate. They are dark, they do not represent what a good EL34 is all about. GL is a better bass valve but poor, at what an EL34 is.
An El34 has Poor bass, good mid bass, slightly bloated mids, and silky BUT dynamic highs.
If you want to build around a GL KT77, there is still a LOT better valve Bottom to Top than a GL, especially for the money, PSVANE is another GREAT valve, but it represents an EL34 sound, but can fetch 2-800.00 for some of their "special" valves, LOL special price. WAY to much..
BTW, 220 mA on the 6 Pac if your cranking it, Late night listening, 240-50, just don't crank it, better low volume listening.
Regards