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Which KT-88 tube?

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Hello everyone,

I had purchased a quad set of Gold Lion Genalex KT-88's a while back and it appears that one of the tubes is showing signs of getting bad, as the measurement of my DMM is indicated a problem with the voltage reading being out of tolerance. Anyhow, I looked around the web for other info on tubes with good reviews. I found two that I would be interested in, so I would like to ask you guys here if I would be making the right choice. The first tubes are called Shuguang KT88-Z (KT88) Treasure series, and the other would be the (SED) Winged "C" KT-88. The company that has the Shuguang tubes is located in China, but am skeptical of sending money there. Here is the website: Shuguang KT88-Z (KT88) Treasure Match Pair_Beam Tetrode_Shuguang Tube_Analog Metric - DIY Audio Kit if anyone can give me info on what tubes would be my best choice/s, it would be deeply appreciated! One last question- I breifly saw the Emission Labs tubes and was wondering if these would be a good choice, and also wondering if I could get them in the KT-88 size? Thanks for any information!!!
 
Hello Steven! Thanks for the comment! I have heard the Winged "C" EL34 tubes, as I have another tube amp that I had purchased years back, in which I had swapped out the oem tubes for the Winged "C" EL34's. I can say that they did make an improvement in sound for the better. I now have 2-mono amps that I have been running for some time using the Gold Lion Genalex KT88's. I do like the way the GL tubes sound. Just recently, I checked the voltage on them, and they are usually set at around 90.5mV. The latest measurements indicated that one of the tubes were begining to go out, as the voltage reading was out the norm. I checked around the web for reviews on KT-88's and found the Shuguang KT88-Z Treasure series had a good review. I was wondering if someone else here may have used them and could give me some input. The winged "C" KT-88 are another one I may be interested in as well as the Emission Labs tubes. I am wanting to get some feed back here to see what some of the other people here have to say about them. Thanks again!
 
Can you elaborate what you mean by 'Checking the voltage' - Did you put them on a tube tester; or were you looking at the bias ? If you are talking about bias; all tubes will drift at one time or another....What amplifier are you using ? It maybe as simple as readjusting the bias....
 
Hello everyone,

I had purchased a quad set of Gold Lion Genalex KT-88's a while back and it appears that one of the tubes is showing signs of getting bad, as the measurement of my DMM is indicated a problem with the voltage reading being out of tolerance. Anyhow, I looked around the web for other info on tubes with good reviews. I found two that I would be interested in, so I would like to ask you guys here if I would be making the right choice. The first tubes are called Shuguang KT88-Z (KT88) Treasure series, and the other would be the (SED) Winged "C" KT-88. The company that has the Shuguang tubes is located in China, but am skeptical of sending money there. Here is the website: Shuguang KT88-Z (KT88) Treasure Match Pair_Beam Tetrode_Shuguang Tube_Analog Metric - DIY Audio Kit if anyone can give me info on what tubes would be my best choice/s, it would be deeply appreciated! One last question- I breifly saw the Emission Labs tubes and was wondering if these would be a good choice, and also wondering if I could get them in the KT-88 size? Thanks for any information!!!

What kind of amp are these going to be finding a home in?

Even before I got into this forum, I was out shopping and ended up getting a pair of Preferred Series KT88 in a round the world about way from the tubestore.com (btw, they are a site sponsor here). It is their own branded tube and when I first heard the tubes, I ran it as a comparison between the Preferred Tube and a pair of GED tubes a friend had.

KT88 Tube Types

The old GED tubes had one strange problem -- they were not as secure as the rest. I figured out by looking at the legs that they were slightly skinnier (took a micrometer to it too) and were looser in the socket.

Compared to the GED KT88, it was difficult to tell other than the GED sounded a little more musical in SE triode mode versus the ultralinear mode whereas the Preferred sounded about the same as the GED in ultralinear mode. This is some jazz and blues out of the updated Mikael Abdellah's KT88 SE Tube Amplifier using a pair of older speakers (forgot which brand those were). The tone was definitely there in both in ultralinear. In triode mode, the Preferred KT88 tubes were tack sharp.

The Preferred ones were also very new having maybe 10+ hours of burn in.

The previous owner of my tubes was a friend of mine who had bought and compared them to a pair of daily use JJ KT88 tubes and a few others. He mailed them as he didn't want them anymore. He didn't like the Preferred KT88 enough to keep them (aesthetics possibly?) and said that the Preferred tube sounded better than the JJ and sounded "fuller" and was comparable to a good number of his KT88. So he had something to compare them to... then again, this is a guy who at first glances looks like he collects tubes and amps and has them all displayed and stuffed into a small space.

I am staring at the KT88s right now and they are going into project number one of mine, (either an updated Mikael Abdellah's KT88 SE Tube Amplifier or the Bob Latino ST-70). The tubes are shiny with triple getters and base and they were the right price.

Hope this helps and maybe gives you one more KT88 to consider.
 
I have about a thousand hours on them running them close to their max ratings.

I had this with New Edit TungSols 6550's....everything seemed happy... then the quiescents started to drift as the 2000 hrs ballpark arrived and the getters started to look sulky...expect anything.

The cue was outgassing due to improper annealing, (takes time) so manufacturers put 3 getters in to deal with the manufacturing shortcut..

richy
 

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Can you elaborate what you mean by 'Checking the voltage' - Did you put them on a tube tester; or were you looking at the bias ? If you are talking about bias; all tubes will drift at one time or another....What amplifier are you using ? It maybe as simple as readjusting the bias....

Steve, I was refering to setting the bias as my amps have connectors that are located on the top, along with an adjustable pot, that allow me to measure and adjust the voltage.

The brand of the amps are Oddwatt Audio. They are called Odd Block series 2. You can view them here: OddWatt

Thanks again!
 
No problem. If I can figure out how to properly upload pictures here, then I will take a few snaps and you can take a look.

For me, it will be good to hear what your experiences are and what you will ultimately purchase. I think that when my project number one will be finished, I will probably have to make some more purchases to make in the KT77, KT88, EL34, and 6550 areas.
 
No problem. If I can figure out how to properly upload pictures here, then I will take a few snaps and you can take a look.

For me, it will be good to hear what your experiences are and what you will ultimately purchase. I think that when my project number one will be finished, I will probably have to make some more purchases to make in the KT77, KT88, EL34, and 6550 areas.

It has been some time since I uploaded pictures. I will try and see if this works. If I remember correctly, you need to upload your pic/s to a site like Image Shack, then click on the icon that looks like a letter. If you place your cursor on it you should see Insert image. Just use the link that you uploaded on Image Shack, and that should do it. I am not 100% on this, but will try and load a pic of the OddWatt amps I have.

An externally hosted image should be here but it was not working when we last tested it.


I am using my Winged "C" (SED) EL34's in them now. They do sound good, but i believe I will like the sound of the Shuguang KT88-Z (KT88) Treasure series better. Also the KT-88's will have around 25 watts vs the 15 watts from the EL34's. By the way, I did try some JJ KT-77's and like the Winged C's better!
 
I would adjust the bias back to where it needs to be; and see how things go over a couple of hours. Naturally tubes age - but the only way to really tell if they need replacement or not is to toss them on a tube tester. I regularly check and adjust my bias every 6mo or so.
 
I recently replaced a set of re-issue Gold Lions KT-88 with a set of Psvane KT-88 T-series in my SE. From the Psvane site "The Psvane T-series black bottle tubes are a further development over the highly sought after Shuguang Treasure Z-series, which was originally first launched by Grant Fidelity in Jan 2009 in North America as Shuguang’s first take on high end vacuum tubes."

I found the Psvanes produced a wider and deeper sound with more detail. Though a bit pricey not an upgrade I have regretted.
 
I recently replaced a set of re-issue Gold Lions KT-88 with a set of Psvane KT-88 T-series in my SE. From the Psvane site "The Psvane T-series black bottle tubes are a further development over the highly sought after Shuguang Treasure Z-series, which was originally first launched by Grant Fidelity in Jan 2009 in North America as Shuguang’s first take on high end vacuum tubes."

I found the Psvanes produced a wider and deeper sound with more detail. Though a bit pricey not an upgrade I have regretted.

Hello Fandersen,

Thank you for passing that info to me! I also have the Gold Lions Genalex KT88's, and have had them for some time. I usually check the bias on them from time to time and recently noticed that the voltage was out of range. I tried adjusting the pot, but could not get the voltage correct. I know sooner or later that there will be a failure.

At first I was going to order another set, but I looked around for some reviews for the KT-88's and found that the Shuguang Treasure series had a good review. I was also considering the Winged "C" (SED) KT-88's, as I have the winged "C" (SED) EL34's.

There is a company in China that claims to have the Shuguang KT88-Z (KT88) Treasure series. I tried emailing them about 5 days ago, but have yet to get a response. I am now very skeptical about ordering from them now.

You have mentioned that the tubes you replaced your Gold Lion KT88's with are the Psvane T-series black bottle tubes. Would these have the same sound characteristics as the original Shuguang KT88-Z treasure series?

Based upon your experience with having listened to the Gold Lion KT88's versus these Psvane T-series black bottle tubes, how would you rate each one on a scale of 1-10.

Thanks again for that info!
 
Its not a good thing to run reissue GL Kt88 close to Max dissipation rate. I'd stay within 35-36W Max. I had the same problem with Quad forty II amps and GL Kt88 . It is self biased circuit which runs tubes at 39-40W i.e 90% of Max. After few hundreds of Hrs one of the went into thermal runaway meaning slowly creeping up bias up to the point when undersized 6W cathode bias resistor burned out. There are many stories like that with GL reisue. Its a good sounding tube though. I bought Penta labs chinese uprated Kt88 (also not cheap).
How do you find Odblock amps ? My dealer who caries ARC line also have a pair (with GL kt88 as well :) I did not listen to them but noticed how small Iron is in those amps. Aprox. 1/3 as big as in any other PP amps he's carring.
 
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