KT-77 tubes
- Thread starter JeffB
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MetalManiac
Li'l Junior Member
Re: KT-77 tubes
https://www.google.com/url?sa=t&rct...ssCn9xW0QvXPPWy_Q&sig2=PIAAOobhyHEuScqkY1ICvg
might be better finding a good used set of old 6ca7.
https://www.google.com/url?sa=t&rct...ssCn9xW0QvXPPWy_Q&sig2=PIAAOobhyHEuScqkY1ICvg
might be better finding a good used set of old 6ca7.
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Re: KT-77 tubes
I looked up quick for some info regarding NOS makers of these. Just Gold Lion name came up.
The current genelex gold lions are made in China right? I wonder how they got the prices to be twice that of JJ.
I have used/using jj 6ca7s for a couple of years now. It's a much different sound than their regular old el34. I noticed they have reworked the design on their el34 & released it as el34ii. Anyone of you guys try that one out?
I looked up quick for some info regarding NOS makers of these. Just Gold Lion name came up.
The current genelex gold lions are made in China right? I wonder how they got the prices to be twice that of JJ.
I have used/using jj 6ca7s for a couple of years now. It's a much different sound than their regular old el34. I noticed they have reworked the design on their el34 & released it as el34ii. Anyone of you guys try that one out?
JeffB
Let it B
Re: KT-77 tubes
My understanding is the new Golden Lions (new sensor) are Russian.. but they have a cheaper chinese version of their 12ax7 which is the same as the tad 7025/preferred series 7025/ruby hg7+ or whatever. Im not 100% though.
In the link Jerry posted, someone has a clip up on youtube comparing the JJ EL34s (two versions) to the JJ KT77s. The 7s sound good IMO. Different for sure. The Golden Lion versions are supposed to be a far better sounding tube though(?)
Are 6ca7s interchangable with el34s? ...meaning, just properly bias and good to go..no component changes needed like 6550s?
My understanding is the new Golden Lions (new sensor) are Russian.. but they have a cheaper chinese version of their 12ax7 which is the same as the tad 7025/preferred series 7025/ruby hg7+ or whatever. Im not 100% though.
In the link Jerry posted, someone has a clip up on youtube comparing the JJ EL34s (two versions) to the JJ KT77s. The 7s sound good IMO. Different for sure. The Golden Lion versions are supposed to be a far better sounding tube though(?)
Are 6ca7s interchangable with el34s? ...meaning, just properly bias and good to go..no component changes needed like 6550s?
Re: KT-77 tubes
Yeah no component change needed for el34 to 6ca7, only rebias. I was lucky to get a set of each from the same grade, so both end up giving same plate voltage readings & are biased to same value, I haven't tried mixing one of each though.
I remember reading the jj 6ca7 design is different from NOS & something similar about the ehx one as well but the ehx version is supposed to sound closer to Sylvania 6ca7 tone. Next time I'd like to give the ehx version a try.
Yeah no component change needed for el34 to 6ca7, only rebias. I was lucky to get a set of each from the same grade, so both end up giving same plate voltage readings & are biased to same value, I haven't tried mixing one of each though.
I remember reading the jj 6ca7 design is different from NOS & something similar about the ehx one as well but the ehx version is supposed to sound closer to Sylvania 6ca7 tone. Next time I'd like to give the ehx version a try.
Lake Placid Blues
New member
Re: KT-77 tubes
There was an early batch of EH 6CA7s that would not bias in many amps with out component changes, but otherwise most 6CA7's, including EH, should go right in in place of EL34s with just a re-bias. In my experience 6CA7s sound like EL34s but with more bottom and more clean head room.
I have not used any current production KT-77s but the general consensus is that they beef up the bottom some AND also make the highs brighter without completely scooping out the mids. It goes without saying that they increase headroom before distortion and make the on set of clipping more abrupt compared to standard EL34s in the same amp. That could be really good in a channel switching amp for the clean channel.
The current Tung Sol EL34B has more bass than standard EL34s. The TAD EL34B has good reviews.
There was an early batch of EH 6CA7s that would not bias in many amps with out component changes, but otherwise most 6CA7's, including EH, should go right in in place of EL34s with just a re-bias. In my experience 6CA7s sound like EL34s but with more bottom and more clean head room.
I have not used any current production KT-77s but the general consensus is that they beef up the bottom some AND also make the highs brighter without completely scooping out the mids. It goes without saying that they increase headroom before distortion and make the on set of clipping more abrupt compared to standard EL34s in the same amp. That could be really good in a channel switching amp for the clean channel.
The current Tung Sol EL34B has more bass than standard EL34s. The TAD EL34B has good reviews.
beaubrummels
Well-known member
Re: KT-77 tubes
IME
6CA7 - Bright, full range, slightly higher threshold before break up (around 7-8 on my Marshall dial) (not as high as 6L6) doesn't sound like EL34 or 6L6 or KT-77
EL-34 - Well-known rock tone, breakup starts around 6-7, but depends on manufacturer/model whether they make 'that' sound; Svetlanas are harsh in my JCM900, Mullard RI are just ok (had them in a Traynor), JJs are pretty good; best bet might be TAD select tubes
KT-77 - Lowest threshold before onset of break up (starts down around 4), the JJ KT-77s I have sound more like 1970's Tesla EL-34s than anything else available now that I've heard
IME
6CA7 - Bright, full range, slightly higher threshold before break up (around 7-8 on my Marshall dial) (not as high as 6L6) doesn't sound like EL34 or 6L6 or KT-77
EL-34 - Well-known rock tone, breakup starts around 6-7, but depends on manufacturer/model whether they make 'that' sound; Svetlanas are harsh in my JCM900, Mullard RI are just ok (had them in a Traynor), JJs are pretty good; best bet might be TAD select tubes
KT-77 - Lowest threshold before onset of break up (starts down around 4), the JJ KT-77s I have sound more like 1970's Tesla EL-34s than anything else available now that I've heard
Lake Placid Blues
New member
Re: KT-77 tubes
Wow, not disputing that, but that is certainly counter to the known performance of the original KT-77s.
beaubrummels
Well-known member
Re: KT-77 tubes
The JJ's I have exhibit a really long ramp into full distortion, but sounds great at every point along the way, from mild break up to howling distortion. I have no idea what 'real' KT-77's used to sound like or perform like. I only have experience with these current production JJ's.
The JJ's I have exhibit a really long ramp into full distortion, but sounds great at every point along the way, from mild break up to howling distortion. I have no idea what 'real' KT-77's used to sound like or perform like. I only have experience with these current production JJ's.
JeffB
Let it B
Re: KT-77 tubes
FWIW- Ive had the TAD el34s and I currently run the Mullard RI. I prefer the TADs and I would buy them again.
The Mullard RI are good, but are too smooth/compress too much for my tastes and a little dull/hazy. This is why I am looking at other options right now. I want a little more raunch and clarity (starting to wonder if I should just buy a Bassman , or HIWATT and be done with it)
FWIW- Ive had the TAD el34s and I currently run the Mullard RI. I prefer the TADs and I would buy them again.
The Mullard RI are good, but are too smooth/compress too much for my tastes and a little dull/hazy. This is why I am looking at other options right now. I want a little more raunch and clarity (starting to wonder if I should just buy a Bassman , or HIWATT and be done with it)
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Lake Placid Blues
New member
Re: KT-77 tubes
In that case you might like the EH 6CA7. It's not an expensive experiment.
In that case you might like the EH 6CA7. It's not an expensive experiment.
Lake Placid Blues
New member
Re: KT-77 tubes
A few days ago I tried a few sets of different EL34/6CA7, and a set of KT-66s based on curiosity from this thread.
The best EL34 set in my opinion was an old =C= and a used but good Siemens (odd ball's that lost their mates but bias up about the same) Every nuance and detail of the mid range was there. Strong but tight bass, and balanced across the spectrum. I have several sets of used EL34s (=C=, Tesla, JJ, TAD..)
KT-66s sound much more Fendery but the bass is huge compared to a regular 6L6/5881, and they are not scooped. The JTM45 sounds much like a fat bassman with these but you must turn the bass knob way down. Using the bridge pickup its not too bassy but it can be with a neck pickup.
The EH 6CA7s sound pretty close to old Sylvania 6CA7s and sounded really good in this test to my ears. Solid bass and sweet highs with more clean head room. Just a bigger, fatter, sound. They sound much closer to any of the EL34 sets than to the KT-66s (I only had one 6L6GC on hand with out a mate so couldn't try it for comparison's sake).
I didn't have any KT-77s or JJ 6CA7s on hand.
A few days ago I tried a few sets of different EL34/6CA7, and a set of KT-66s based on curiosity from this thread.
The best EL34 set in my opinion was an old =C= and a used but good Siemens (odd ball's that lost their mates but bias up about the same) Every nuance and detail of the mid range was there. Strong but tight bass, and balanced across the spectrum. I have several sets of used EL34s (=C=, Tesla, JJ, TAD..)
KT-66s sound much more Fendery but the bass is huge compared to a regular 6L6/5881, and they are not scooped. The JTM45 sounds much like a fat bassman with these but you must turn the bass knob way down. Using the bridge pickup its not too bassy but it can be with a neck pickup.
The EH 6CA7s sound pretty close to old Sylvania 6CA7s and sounded really good in this test to my ears. Solid bass and sweet highs with more clean head room. Just a bigger, fatter, sound. They sound much closer to any of the EL34 sets than to the KT-66s (I only had one 6L6GC on hand with out a mate so couldn't try it for comparison's sake).
I didn't have any KT-77s or JJ 6CA7s on hand.
GoldenVulture
Braindeadologist
Re: KT-77 tubes
I bought a set of reissue Gold Lion KT88's as a backup for my NOS Gold Lion KT88's. The sound quality of the reissues is very respectable in comparison to the NOS's.
I bought a set of reissue Gold Lion KT88's as a backup for my NOS Gold Lion KT88's. The sound quality of the reissues is very respectable in comparison to the NOS's.
