JJ KT77 vs Genalex KT77 Shootout

belensky

Member


Amp settings, and recording chain exactly the same, both sets set to 65mA per pair.

I don't know about you guys, but I had already two sets of JJ KT77, that dying in my Diezel Herbert, first set (that eventually I got replaced under warranty) started to make troubles after 6 mouths: one of tubes starters to glow almost like a light bulb, second set started to do the same thing after year.
I bought more expensive set of Genalex Gold Lion KT77. I hope they will work longer than JJKT77, because it's quite frustrating and expensive to retube Herbert every year.
have anyone had same problems with JJ KT77, or it's just me or some bad batch of tubes in shop?
 
I got a quad of JJ KT77s about 2 months ago that just failed as well. I'm going through the process of exchanging for a new set, but you got me thinking of trying the Gold Lions now.
 
Pretty batch/production specific IMHO... I know a whack of manufacturers have gone with JJs in the last few years due to cost, consistency and durability. Before that, some were going with Ruby (rebranded Chinese, Shug, Sino, who knows...). The tubes that come stock from a manufacturer are usually chosen after careful consideration of fail-rates and overall "quality of sound". They likely won't stock an already expensive amp with another $500+ in glass as that just adds to the amp's retail price, so it's left to the end-user purchaser to work with what they get.

I've had Gold Lion 77s in a number of my amps, and they've sounded fantastic, and they've lasted (in 2 of my amps) an incredibly long time (we're talking YEARS...!!). And these amps spend their time 50/50 between bedroom levels to fucking cranked and everything in between. I often go full-retard on my amps to really test them out - 3 o'clock or more on the MVs, and the same or dimed on the channel volumes....just to hear how everything's "fitting together" - are the tubes crackling and cackling, any artifacts floating about, how's the hiss, how's the attack/feedback/microphonics. I play them at these levels quite often - WAY beyond what a band context would accommodate, but just to know "they can" and "without issue" run at these levels.

Tangent - sorry. The GL77s are pricey, but have sounded great and lasted a long time in the amps I've had them in. NOS Winged =C= are great if you buy from a reputable seller https://www.thetubestore.com/winged-c-sed-el34. And I've heard great things about the New Sensor reissued Mullard and Svetlanas.

Recent Diezels have come stock with JJ77s and they sound great and haven't given up the ghost just yet. When they do? I'll likely opt for one of the aforementioned brands...but so far, no issues.
 
Ventura":38pf4aa9 said:
Pretty batch/production specific IMHO... I know a whack of manufacturers have gone with JJs in the last few years due to cost, consistency and durability. Before that, some were going with Ruby (rebranded Chinese, Shug, Sino, who knows...). The tubes that come stock from a manufacturer are usually chosen after careful consideration of fail-rates and overall "quality of sound". They likely won't stock an already expensive amp with another $500+ in glass as that just adds to the amp's retail price, so it's left to the end-user purchaser to work with what they get.

I've had Gold Lion 77s in a number of my amps, and they've sounded fantastic, and they've lasted (in 2 of my amps) an incredibly long time (we're talking YEARS...!!). And these amps spend their time 50/50 between bedroom levels to fucking cranked and everything in between. I often go full-retard on my amps to really test them out - 3 o'clock or more on the MVs, and the same or dimed on the channel volumes....just to hear how everything's "fitting together" - are the tubes crackling and cackling, any artifacts floating about, how's the hiss, how's the attack/feedback/microphonics. I play them at these levels quite often - WAY beyond what a band context would accommodate, but just to know "they can" and "without issue" run at these levels.

Tangent - sorry. The GL77s are pricey, but have sounded great and lasted a long time in the amps I've had them in. NOS Winged =C= are great if you buy from a reputable seller https://www.thetubestore.com/winged-c-sed-el34. And I've heard great things about the New Sensor reissued Mullard and Svetlanas.

Recent Diezels have come stock with JJ77s and they sound great and haven't given up the ghost just yet. When they do? I'll likely opt for one of the aforementioned brands...but so far, no issues.



Couldn't have said it better.
 
I posted this reply on your YT video as well:

I agree that the JJ sound more tight and clear. I especially prefer the clean sound. The tube life issue may have to do with the tube socket grid bias resistance value with regard to the 250k limit of the JJ KT77 reported by JJ Electronics, at least partially due to the absence of the pin 1 connection they chose for compatibility with Fender Twin amps. Try to find out what the total grid bias R value is in the amp and lower it to no more than 250k per socket. You'll likely just have to change the bias feed resistors to achieve 250k per tube.

Then you can bias the KT77 tubes up to ~80% dissipation without concern, but with a ~20% shortened life. It's an easy and very cheap mod once you find the resistors to change, and I doubt you'll notice a difference in the sound. It has to do with blocking distortion and high end. Lower R values will have both more high end and blocking distortion, but the speakers are really the limiting factor there.
 
belensky":3h08khw0 said:


Amp settings, and recording chain exactly the same, both sets set to 65mA per pair.

I don't know about you guys, but I had already two sets of JJ KT77, that dying in my Diezel Herbert, first set (that eventually I got replaced under warranty) started to make troubles after 6 mouths: one of tubes starters to glow almost like a light bulb, second set started to do the same thing after year.
I bought more expensive set of Genalex Gold Lion KT77. I hope they will work longer than JJKT77, because it's quite frustrating and expensive to retube Herbert every year.
have anyone had same problems with JJ KT77, or it's just me or some bad batch of tubes in shop?

What IRs did you use for this demo?
 
belensky":ysas21yy said:


Amp settings, and recording chain exactly the same, both sets set to 65mA per pair.

I don't know about you guys, but I had already two sets of JJ KT77, that dying in my Diezel Herbert, first set (that eventually I got replaced under warranty) started to make troubles after 6 mouths: one of tubes starters to glow almost like a light bulb, second set started to do the same thing after year.
I bought more expensive set of Genalex Gold Lion KT77. I hope they will work longer than JJKT77, because it's quite frustrating and expensive to retube Herbert every year.
have anyone had same problems with JJ KT77, or it's just me or some bad batch of tubes in shop?

Hi buddy ! Nice clip again! I guess the JJ retains better when knobs are dimed... well just wanna know if the herbert mk2 transformer designs be able to deliver kt88 or 6550 power tubes? Have checked every bit of herbert clips on youtube and i found the clip which killertone did was better and it holds the amp clarity better...

I anyhow gotten a used Herbert Mk2 and its coming my way very very soon !! Now my head is filling up with what power and preamp tubes to go...

I may wanna try KT77 JJ with two outer 6550 or KT88 for extra tight lowend and clarity...

Any idea or good feedbacks? I heard the Diezel goes well with china 12ax7... but which generation is the better ones? I may have an idea to put a mullards 12ax7 at V1 which i usually do to up the mids more... any ideas?
 
it has nothing to do with size of transformers. bias of Big bottle tubes is different, and tubes are hot, it's not mine words but Peter Diezel himself. it could work, and there are some guys who have 6550 or KT88 in their Diezel but I think there is reason why for last ten years or something Diezel uses KT77. search there are some threads about 6550 with Diezel.
I think it's best to start from stock tubes, let it grow on you for couple mouths and if you feel that you been missing something, then you could start to mess with amp.
 
belensky":etvpfbf0 said:
it has nothing to do with size of transformers. bias of Big bottle tubes is different, and tubes are hot, it's not mine words but Peter Diezel himself. it could work, and there are some guys who have 6550 or KT88 in their Diezel but I think there is reason why for last ten years or something Diezel uses KT77. search there are some threads about 6550 with Diezel.
I think it's best to start from stock tubes, let it grow on you for couple mouths and if you feel that you been missing something, then you could start to mess with amp.

Thanks alot there !! Your right... i see if it still retains stock tubes from diezel.. or i probably go el34s i kinda like more of the mid thing going... seems like kt77 is kinda scooped.
 
I bought a matched quad of gold lion kt77's and one of them failed within 6 months. I've just ordered a quad of JJ KT77's because we're tracking soon and I want to use the VH4 a fair bit for that.

Just no way to really tell if you're buying something that's going to die within 3 months or not. Always a risk.
 
Amberience":2sl8eilg said:
I bought a matched quad of gold lion kt77's and one of them failed within 6 months. I've just ordered a quad of JJ KT77's because we're tracking soon and I want to use the VH4 a fair bit for that.

Just no way to really tell if you're buying something that's going to die within 3 months or not. Always a risk.
If you buy from www.thetubestore.com (Jon & Co.) let 'em know you know Mo, and regardless - they've got a great policy for freak failures when you're cool about it. I've been using these guys forever, and they've never disappointed me.

Peace
 
hopkinWFG":24mkqppj said:
... seems like kt77 is kinda scooped.
Key. Not "seems", this is quite true.

I have both a original Herbert and a Mk2. My original is loaded with El34s and my Mk2 with JJKT77s. Yes the circuitry is slightly different but negligible for this comparison as they are both Diezel Herbert guitar amplifiers.

The difference is beyond question. The El34s are more open (clear) of course with that British grit and grind. Switch over to the JJKT77s and the "protracted compression" is clearly evident.

Ritch, clear, in-your-face.

EL34BSTR-500x500.jpg
 
Giga.Blast":3ua52bjl said:
hopkinWFG":3ua52bjl said:
... seems like kt77 is kinda scooped.
Key. Not "seems", this is quite true.

I have both a original Herbert and a Mk2. My original is loaded with El34s and my Mk2 with JJKT77s. Yes the circuitry is slightly different but negligible for this comparison as they are both Diezel Herbert guitar amplifiers.

The difference is beyond question. The El34s are more open (clear) of course with that British grit and grind. Switch over to the JJKT77s and the "protracted compression" is clearly evident.

Ritch, clear, in-your-face.

EL34BSTR-500x500.jpg

EL34BSTR!! I see.... i could see a clear stand between users from these two tubes... i will give it a try thou thx....
 
hopkinWFG":1qxkh1u5 said:
EL34BSTR!! I see.... i could see a clear stand between users from these two tubes... i will give it a try thou thx....
"O Brother, Where Art Thou?"

Man, I've been down that spiraling rabbit hole for quite a long time.

Sincerely, speaking at great length to any serious rock guitarist about pre/power amp tubes might as well be a lecture in politics.

In my case I've come full circle since 2003. For me, it's Ruby 12AX7AC5 HG+ (high grade+) V1-V6 with Ruby EL34BSTR.

I spent hours over the years going back an forth swapping out JJEL34, JJEL34L, JJKT77 and even Ruby 6L6GCBSTR all through.

In the end, I'm an EL34 guy.

Set Herbert CH3 gain at 4/11:00, volume 12:00, master 9:00 perfect for hard core rock/metal. When the lead section arrives, kick in a good "clean" boost like a Xotic EP booster pedal and just let her sing. The EP is the magic box and 100% "tone" transparent. I suggest you might find it an interesting addition to your audio arsenal.
 
Giga.Blast":fst9mk4v said:
hopkinWFG":fst9mk4v said:
EL34BSTR!! I see.... i could see a clear stand between users from these two tubes... i will give it a try thou thx....
"O Brother, Where Art Thou?"

Man, I've been down that spiraling rabbit hole for quite a long time.

Sincerely, speaking at great length to any serious rock guitarist about pre/power amp tubes might as well be a lecture in politics.

In my case I've come full circle since 2003. For me, it's Ruby 12AX7AC5 HG+ (high grade+) V1-V6 with Ruby EL34BSTR.

I spent hours over the years going back an forth swapping out JJEL34, JJEL34L, JJKT77 and even Ruby 6L6GCBSTR all through.

In the end, I'm an EL34 guy.

Set Herbert CH3 gain at 4/11:00, volume 12:00, master 9:00 perfect for hard core rock/metal. When the lead section arrives, kick in a good "clean" boost like a Xotic EP booster pedal and just let her sing. The EP is the magic box and 100% "tone" transparent. I suggest you might find it an interesting addition to your audio arsenal.

Hahah... your interesting english command!! Lol... well thanks for telling... i have a Fortin grind and 33... i may wanna hook up a VFE standout thou if lucky is on my side if the backers are full on...

But how different is the MK2 vs MK1 ?
 
1st, there never was a Herbert MK1 designation (model). It was just Herbert back in early 2003 and came onto the seen like guitar royalty having already the VH4 firmly planted in the studio recording rock domain as of 1994.

I run a master/slave rig. My master (right) is the original, the slave (left) is the Mk2. I find the original simply better for my taste. The original is clearly less compressed and is recognizable to Herbert players in a A/B test fairly quickly.

Other than that, there's only so much blood you can squeeze from a stone.

Accept for this last acquisition - it's on its way. I've been contemplating this for quite some time and finally pulled the trigger on it today. A Gibson Custom Standard Historic 1957 Goldtop Les Paul R7 - Antique Gold VOS, Dark Back. There might just be a G o d - she plays like butter.
 
Hahah... nice !! I may score an early Herbert again if i have the cash... thx for ya time dude !! And enjoy ya gibby !! Am a jackson guy here ! Lol
 
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