|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
121.54.29.21
Would KT77 tubes be a direct substitute for amps carrying EL34 tubes?
Follow Ups:
Isn't it, That some old circuits were capable of running EL34's in Triode, And the KT77 is a Kinkless tetrode and can't be ran in triode. But in all other pentode circuits it's fine?
Yes, the Genalex KT-77 is a great tube, and it is superb in EL34 applications.
They tend to bias slightly cooler than EL-34s, but I've had no trouble at all selecting tubes that work well in people's EL-34 amps. Of course, if it is adjustable the bias does need adjustment as it does ANY time you change power tubes in a fixed bias amp.
How's the Genalex 12ax7 new production?
-------
I.D.
The earliest batches had tendencies to be microphonic, but the recent stuff is quiet and the microphonics are no longer an issue.
The tube has an excellent tone - but it is pretty warm. You'd probably be better off not combining it with other warm tubes. But I can now recommend it where I couldn't before.
Jim are you saying that the GL KT-77 is warm and now recommended, or are you referring to the GL 12AX7. I would probably like a warm KT-77 in my gear.
I was referring to the 12AX7. The KT-77 is not as warm as some Mullards - but it definitely has some warmth to it.
I always recommended the Genalex KT-77, it's wonderful!!
So the tone of the Genalex KT77 is more transparent and not necessarily warm, say opposed to a EL34?
-------
I.D.
It depends on which EL34 - there is a large sonic difference between say an EH EL34 and a SED EL-34.
I was comparing to EH EL34. That is what I have in my CJ amp and I am wondering what I would expect if I went to GL KT77. Unfortunately, once I buy the tubes (approx $200 for a quad) it is not like I can return it.
-------
I.D.
You'll get a tube with more warmth thatn the EH, which has the least warmth of any EL34 IMHO.The KT-77 is FAR better in the vast majority of case. I really doubt you'd be disappointed.
Edited to fix typo.
Edits: 03/21/12
So Jim, my system already has warmth to it, becuase of other components and speakers (which I do not mind anyway). That is why I added the EH EL34 in the amp to bring a bit more sizzle. Do you think if I went to GL KT-77 it might negate some transparency with added warmth. I know you can't predict, but just want a general opinion. Is there anything that will improve in general, or should I stick to the EH EL34.
-------
I.D.
My guess is yes, the system will sound more restrained.
Why don't you try the 6CA7 EH? That might be just what the doctor ordered! And they are cheap too...
That is a good suggestion. I will give it a try!
-------
I.D.
Does the JJ KT-77 have the same tonal balance at the GL KT77 - warm?
-------
I.D.
I STRONGLY recommend you avoid the KT-77 JJ. I don't carry it because the quality - like that of all JJ octal based tubes - is suspect, to put it mildly.
I would never use a JJ KT-77 in my own gear.
Now I will GUARANTEE that someone will reply and say how they have a set of great JJs. The problem is the % of tubes that aren't great. If you happen to get a set of good JJs they can be nice sounding. Once upon a time they made very good tubes. But not so much anymore; the odds of getting a good set are too long for me to have my customers put them in their own gear.
Sorry!
Thanks for the caution. I will avoid it. Now that I remember, I had JJ E34Ls go kaput on my amp twice, but I never had any issue with the EH EL34s for several years!
-------
I.D.
bought the genelex kt-66 for my primaluna prologue 4 amp few years ago, didn't like it..I liked thge oem el34 tubes better than the kt-66, the russian tubes that Jim McShane sells for $60+ for a quad set was so much more to my liking...
would it have been better if i had purchased the kt-77 genelex tubes years ago instead of the kt-66?
Lucky You Live Hawaii
The KT-66 is a completely different family of tube, so I would have recommended the KT-77 to you. If you like EL-34 tubes then the KT-77 is much more likely to suit you.
Although they are expensive, the Genelex Gold Lion KT-77s are a great replacement for the EL-34s.
I had to increase the bias adjustment of my amps a bit to get it right.
Don't know if they are a direct drop in replacement for non-adjustable-bias amps.
I've had good luck with Jon at Tube Store dot com in purchases as well as info when needed.
FWIW - I preferred the sound in every way with the Genelex KT-77s. Don't know about other KT-77s. They may all be an improvement, AFAIK.
Best regards,
Jim Smith
What about on a auto bias amp like Decware's Torii?
Yes it is. If the unit has 1 or bias adjustments, they (obviously) must be reset.
Eli D.
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: