Valve Art KT66 vs????

[mikepukmel]

One of the guys selling kits sells Valve Art KT66's with an amp kit. Anyone have any preferences for this or another brand KT66?

[Justin Thomas]

Since it looks like a rebranded Chinese KT66 to me, I'd just get whatever Chinese KT66 is cheaper, after matching and testing for noise... But that's me.

Realistically, there's only 3 "brands" of tubes left, anyway: Sovtek, JJ, and Sino/Chinese. Anything else is rebranded. Hence we also have a Tung-Sol KT66 available... (shaking my head)

Justin

[bob p]

When I heard "Valve Art KT66" I immediately thought Chinese.

[Leo_Gnardo]

Valve Art is a Shuguang tube. They're mostly marketed to the hi fi crowd, but their prices tend to be on the low side.

[mikepukmel]

Thanks. Yeah, Leo compared to others, 63.00 a matched pair, TungSol 70, Genalex Gold Lion 80, then some new old stock bull for 700.0 a pair. Not in my budget this week

You see any longevity problems with Shuhuang?

[mikepukmel]

Since it looks like a rebranded Chinese KT66 to me, I'd just get whatever Chinese KT66 is cheaper, after matching and testing for noise... But that's me.

Realistically, there's only 3 "brands" of tubes left, anyway: Sovtek, JJ, and Sino/Chinese. Anything else is rebranded. Hence we also have a Tung-Sol KT66 available... (shaking my head)

Justin

I read myself around in circles. Find a few complaints about brand Y, then someone says Brand Z is Russian, never had a problem, then a bunch of posts about the russian tubes that failed, back around to just buying cheaper since they're all the same anyway. And, get 2 sets, or 3

So, the Genalex Gold Lion's aren't worth the price, except unless you like the little boxes up there on the shelf to look at?

Ohhh, and one brand 'reissue' grounds the case to pin1 like the old metal can tubes did?

[Leo_Gnardo]

I read myself around in circles. Find a few complaints about brand Y, then someone says Brand Z is Russian, never had a problem, then a bunch of posts about the russian tubes that failed, back around to just buying cheaper since they're all the same anyway. And, get 2 sets, or 3

So, the Genalex Gold Lion's aren't worth the price, except unless you like the little boxes up there on the shelf to look at?

Ohhh, and one brand 'reissue' grounds the case to pin1 like the old metal can tubes did?

The prices on VA seem to have taken a jump since the last time I looked. I'd have to say, not much point in trying KT66 unless you're really willing to spring for the extra cost, just for an experiment. Also, the glass bulbs are a bit larger than 6L6's and you may have a tough time wedging them into a Bassman head box. On combo amps the extra weight helps gravity drop them from their sockets.

Haven't personally seen any "Gold Lion" genelex so-called reissue KT66. But I recently had a look at their KT88. Inside the glass, looks exactly like Sovtek/EH KT88 and 6550. I wouldn't be surprised if it's yet another of New Sensor's tricks, applying a venerable logo to the glass and charging an premium price while claiming the product is an "authentic reproduction." Might be much the same for Valve Art - I see a 6L6 plate in a big bulb, big deal. But there's no way know for sure without buy, try, and maybe dissect one and compare it to the original item.

In fact I DO keep a pair of real original Genelex KT88 boxes on the shelf for nostalgia's sake. How did you know ???

I don't know anything about base wired to pin 1 on any of these. And it's not grounded unless you ground it. These are beam tetrodes so pin 1 presumably isn't attached to any of the tube elements anyway. You would only have to worry if it was jumpered to pin 8 on the socket, as it often is, and you're running a self-bias circuit.

[soundmasterg]

When they first came out the Valve Art KT66 had a good reputation as sounding like the vintage Genelex but not lasting as long, since no modern tubes last as long as the vintage ones. All that I have heard about them since still says the same thing. As said by others, the Valve Art is just a Shuguang tube, though perhaps it is selected and/or tested. I think the cheapest place that you get the Shuguang that I have found is from Ted Weber.

https://www.tedweber.com/kt66

Greg

[mikepukmel]

The prices on VA seem to have taken a jump since the last time I looked. I'd have to say, not much point in trying KT66 unless you're really willing to spring for the extra cost, just for an experiment. Also, the glass bulbs are a bit larger than 6L6's and you may have a tough time wedging them into a Bassman head box. On combo amps the extra weight helps gravity drop them from their sockets.

Haven't personally seen any "Gold Lion" genelex so-called reissue KT66. But I recently had a look at their KT88. Inside the glass, looks exactly like Sovtek/EH KT88 and 6550. I wouldn't be surprised if it's yet another of New Sensor's tricks, applying a venerable logo to the glass and charging an premium price while claiming the product is an "authentic reproduction." Might be much the same for Valve Art - I see a 6L6 plate in a big bulb, big deal. But there's no way know for sure without buy, try, and maybe dissect one and compare it to the original item.

In fact I DO keep a pair of real original Genelex KT88 boxes on the shelf for nostalgia's sake. How did you know ???

I don't know anything about base wired to pin 1 on any of these. And it's not grounded unless you ground it. These are beam tetrodes so pin 1 presumably isn't attached to any of the tube elements anyway. You would only have to worry if it was jumpered to pin 8 on the socket, as it often is, and you're running a self-bias circuit.

Hi Leo, sorry, misread on the first read: its a new amp. The fender type build sounds good, so moving on to a marshall type thing, a JTM45 smelling thing that has KT66's. I'll look up the article about teh tube with the reference about pin1 ground maybe they were wrong. The only other article about KT66's that seemed relevangt was about the size of the things, if you had certain amps, some tubes are so wide they won't fit together. I hope the spacing is right on this chassis, don't know how to tell until I get the tubes in.

[mikepukmel]

When they first came out the Valve Art KT66 had a good reputation as sounding like the vintage Genelex but not lasting as long, since no modern tubes last as long as the vintage ones. All that I have heard about them since still says the same thing. As said by others, the Valve Art is just a Shuguang tube, though perhaps it is selected and/or tested. I think the cheapest place that you get the Shuguang that I have found is from Ted Weber.

https://www.tedweber.com/kt66

Greg

Thanks Greg, looking at weber's site now. Is it worth it to get matched, burned in tubes, or just wasting $?

[Justin Thomas]

While most of my amps have both a bias balance and adjust, so matching isn't quite as relevant to me, the fact that they were plugged into SOMEthing at SOME sort of high voltage before I got them is worth it. Culling out the duds that short upon first fire-up is worth it to me, personally. Matching &/or burn-in is more about infant mortality than tone or longevity, to me.

Generally, I plug any new 6L6-style tubes in my Bassman and match them myself. I use a lot of pulls from used amps I buy.

Justin

[soundmasterg]

Thanks Greg, looking at weber's site now. Is it worth it to get matched, burned in tubes, or just wasting $?

With today's tubes and the often poor quality, matching is often a good idea. I also use dual bias pots in any amp I build so matching isn't as big of a concern as I can match stuff up within reason, but the idea that matching gives one layer of testing above the manufacturer making the tubes and sending them to the dealer to be sold probably gives a little better guarantee of the tubes working is what matters I think.

Greg

[g1]

I don't know anything about base wired to pin 1 on any of these. And it's not grounded unless you ground it. These are beam tetrodes so pin 1 presumably isn't attached to any of the tube elements anyway. You would only have to worry if it was jumpered to pin 8 on the socket, as it often is, and you're running a self-bias circuit.

About the pin1 connected to tube base thing:
Standard Fender (and others) wiring is pin1 as tie point for grid stopper to pin5, carrying bias. Now you put in one of these funny tubes with metal base connected to pin1. You might get a little tickle removing the tube on stand-by. More importantly, if you use some kind of retainer clamp or spring that touches the base, you have shorted your bias to ground.

[mikepukmel]

About the pin1 connected to tube base thing:
Standard Fender (and others) wiring is pin1 as tie point for grid stopper to pin5, carrying bias. Now you put in one of these funny tubes with metal base connected to pin1. You might get a little tickle removing the tube on stand-by. More importantly, if you use some kind of retainer clamp or spring that touches the base, you have shorted your bias to ground.

Thanks G1 I was just going to ask that very same question in another post: why don't the many JTM45 layouts e.g.
http://music-electronics-forum.com/a...5ceriatone.jpg

use pin1 to park one side of the grid stop, like the Fenders do. All of the KT66 data sheets i can find, Genalex JJ, etc, have N.C. on Pin1 like the 6V6's do.

Most of the JTM45 layout kits have one end of the KT66 grid stop on the pin ,and the other end flapping in the wind. I kinda hate that.

I have some photos of a beautiful build, I know its from music-electronics-forum, but damned if I can't remember whose built it was.

he used these pins that look like they screw into the chassis, but there's an insulator then a pin on top, so you can solder stuff to the top and it won't ground to the chassis (I think anyway).



Wish I could remember who did the build but anyway see the mount between the 1 ohm (or whatever) bias check resistor? Anyone know where I can find those?

[mikepukmel]

Feel kinda stupid now, I think its a banana plug jack? Mount 3, put two bias check resstors between, then the middle would be grounded,. I think.