Shuguang Treasure tubes - KT88

KptKrunch

Member
Since Audio karma is now hosting the forum for GF, though it would be a good time to start this thread.

I recently purchased some black bottle KT-88 tubes from Ian for my GF-A88 amp. I'm also running the TJ Full Music 12AX7 preamp tubes in place of the shugaung stock, and just (will be getting them right away actually - literally -they're here at the post office and I'm going once this post is done) getting some NOS Sylvania Chrome Dome 1940's 6SN7GTB's (supposed to be the best sounding GTB's according to those in the know).

I'll post pic's and impressions soon. Just wanted to get this thread started. I will say that so far very impressed with the Treasures. However, I only have 15 hours on them so far, and it could a while before I get a chance to put more on (#1 we're in the middle of a heat wave, listening to tubes with no A/C is not my idea of fun and #2 I'm in the middle of a backyard project which I also have to get back to right away).

I am keeping a diary on these tubes though, and will make a rather long post as these thing break in. I'll make my initial listening report at about the 100 hour mark. Hopefully it will help out anyone looking at getting these tubes for their own gear.
 
A customer has just posted some feedback on AudiogoN

to share with everyone:

Posted by happy customer John on AudiogoN: original post here:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1248723961



Shuguang Treasure tubes....

I'm not sure if this is in the right place but this is about the tubes in my amp so here goes....Has anyone else given these Shuguan Treasure tubes a try?
I recently bought a used tube amp(VAC Phi 110) and the tubes that came with it were shot so I started poking around for some new tubes. I was looking for some Shuguang tubes, which are what I believe VAC supplies as standard/stock, and ran across Shuguangs limited production Treasure tubes. I poked around and did some reading, found a review or two and decided to give the only distributer for N. America(Grant Fidelity) a call. I spoke to a very kind and helpful lady who was patient with me(quite the task I might add!), was very nice and helpful and was darn knowledgeable on the tubes. Before I knew it my wallet had leapt out of my back pocket and I had splurged and ordered a matched quad of the Treasure Tubes, KT-88s. Within a couple of hours I had a tracking number and about a week later a box labeled "FRAGILE: GLASS!" was waiting for me when I got home from work.(A quick side note; during the short wait for the Treasure tubes to arrive I was using a borrowed quad of stock VAC KT-88 tubes and they were wonderful, great sounding tubes that I could live with forever....or that is until I found the Treasure tubes anyway.)

When the Treasure tubes showed up I ripped into the box and was shocked to see that each pair comes in a really nice presentation box with each tube very well protected in a foam insert, very classy. I removed the tubes, admired their beauty(they really are sweet looking tubes!) and popped them in the VAC and let them warm up for about 15-20 minutes. I then set bias on them and hit the play button expecting the usual tube break in time-wrong!...right out of the box these tubes sound fantastic! Seriously, I am shocked how at just good they sound fresh out of the box. Smooth clean highs, strong deep bass and all the other audiophile words we so endear. If they're this good right out of the box I can't wait until I get 100 hours or so on them. I'm no reviewer but I can say that these tubes offered a noticable improvement in my system and are worth every penny of their asking price, no doubt about it! So far they are chugging along and sounding beautiful and hold a rock solid bias, ZERO fluctuation.

Please understand that I have no affiliation with Grant Fidelity but when I run across a company that treats their customers so well and offers a product that performs at this level I feel I should share my experience with others, I'm one VERY hapy audionut!

Yes I actually do have a question and here it is; They(Grant Fidelity/Shuguang) also offer a 6SN7 substitute called the "CV-181", this is supposed to be a direct replacement for standard 6SN7's and I'm very interested in those as well. Has anyone else had the opportunity to give these tubes a try? Thanks for your replies.

Sincerely,
John

Johngp (Answers)
07-27-09
 
Hi just wanted you to know I use the CV-181 tubes on my GRANT FIDELITY A348 tube amp. Sounds wonderful.
I have the TREASURE CV-181, TJ 12ax7, TREASURE KT88-z, TREASURE 6CA7-z, And waiting for my paid for TREASURE 300B-z.

Sorry as you can tell I have 2 tube amps THE GF A-348 and the GF A534-B and the tubes are spread out on the 2 units.
The 181 tubes are a best buy regardless of price. To get a even close sounding tube you end up going NOS at twice the price or more.
 
Too bad their so expensive or I would try them.


Rick

Which ones? I haven't really seen any 'cheap' KT-88 tubes out there per say. Unfortunately, I only have about 54 hours on my tubes right now, I'm waiting to get to 100 hours before I start swapping tubes back (to the original stock ones) to see what the difference is (in my rig in my room of course) or if the higher price is worth it. From what I've gleaned so far, my A-88 with all the upgraded tubes (I have some 6SN7 NOS Sylvania from the 50's the TJ Full music 12AX7 and the treasure series KT-88's) I feel the amp does have a significant improvement. Best way to describe it is with the stock tubes in place, to get that lush liquid tube sound, I need to operate it in triode mode, which give me 30 watts / channel. I lose that tube sound when I switch to Ultra linear but at 60 watts it sounds cleaner and (obviously) more power means it plays louders without distortion.

With all the tubes I've upgraded with, I get (if memory serves) pretty close to the Triode sound for tone in the Ultra Linear mode (so I still have plenty of power too). But this is over a long period of time. I don't get near as much time as I would like to just sit down and listen. Maybe over Christmas who knows, but once I get 100 hours on these new tubes, I'll switch the old ones back in. Then I have to start switching various ones out to see what (if any) sonic improvement comes from each stage. Lots of work - I'll do the Treasures first, then the 6SN7's, then the 12AX7's, then combinations of them. Not an easy task but should be fun nevertheless. Plan to do that during our next blizzard when I'm stuck at home and have nothing else to do.
 
Which ones? I haven't really seen any 'cheap' KT-88 tubes out there per say. Unfortunately, I only have about 54 hours on my tubes right now, I'm waiting to get to 100 hours before I start swapping tubes back (to the original stock ones) to see what the difference is (in my rig in my room of course) or if the higher price is worth it. From what I've gleaned so far, my A-88 with all the upgraded tubes (I have some 6SN7 NOS Sylvania from the 50's the TJ Full music 12AX7 and the treasure series KT-88's) I feel the amp does have a significant improvement. Best way to describe it is with the stock tubes in place, to get that lush liquid tube sound, I need to operate it in triode mode, which give me 30 watts / channel. I lose that tube sound when I switch to Ultra linear but at 60 watts it sounds cleaner and (obviously) more power means it plays louders without distortion.

With all the tubes I've upgraded with, I get (if memory serves) pretty close to the Triode sound for tone in the Ultra Linear mode (so I still have plenty of power too). But this is over a long period of time. I don't get near as much time as I would like to just sit down and listen. Maybe over Christmas who knows, but once I get 100 hours on these new tubes, I'll switch the old ones back in. Then I have to start switching various ones out to see what (if any) sonic improvement comes from each stage. Lots of work - I'll do the Treasures first, then the 6SN7's, then the 12AX7's, then combinations of them. Not an easy task but should be fun nevertheless. Plan to do that during our next blizzard when I'm stuck at home and have nothing else to do.

I am looking forward to reading your tube reviews, I do appreciate your efforts and it sounds like a long process.
I am new to tube amps..I sold my Edge NL12.1 solid state amp when I was offered a very nice Harmon Kardon Citation I pre-amp and matching Citation II amp. I needed some extra $$ for the home remodel I'm doing (complete renovation, changing layout of rooms, new walls, 100% new electrical and all new plumbing) I hope I don't regret selling the Edge amp.

After reading so much good about the Citation II, I decided to go with it.
I have already gotten all the Jim McShane upgrades/mods for the amp, but I still need to do the work, which pretty much replaces most of the old parts, all "new" NOS vintage Micanol yellow octal and 9 pin tube sockets, and adds a pair of switches (silver contacts) to switch from ultra linear (65 watts) to triode (35 watts).
I am looking to purchase another one of these amps and make a slight rewire to make both run as "mono" amps, @ around 130 watts ultra linear, 65 watts triode.

The recommended "affordable" power tubes for this amp are the Genalex Gold Lion KT88's which are just over $200 for a matched Quad.
When I seen the review of the Treasures, I was eager to find them...then I read the cost, just before I read your post..that is why I answered in the way I did..
The tubes would have to last longer than the standard or I could not afford to spend that much..or, if they are that special, I could use them only at special times.

Just for reference, my system consists of the following:

Speakers:
Green Mountain Audio "Continuum 3"

JL Audio Fathom F113 Sub woofers (2 @ 2500 watts each)

Pre-amp:
VAC CPA MKIII with "Signature" phono mods (sent to Kevin @ VAC and he went completely through it, upgraded everything possible, and brought it to the highest level he could..new tubes and not even 10 hours when I had to box it up because of remodel)

SACD/CD player:
Sony SCD-1

Turnables:
Technics SL-1000 (SP10 MKII with factory Obsidian plinth)
SP10MKII (2nd) for Slate plinth project
Goldring G99 (Lenco) waiting for plinth project
Various other Lenco's
Empire 208 waiting for project
Luxman PD-121 wanting to try in solid plinth

Reel to Reel:
Akai GX-646

Tuner:
Sansui TU-9900

Hm...I added more than I needed, I'm really missing my system..all boxed away... once I got started trying to remember what I have boxed away, I was also telling myself what I have :scratch2:

Well, this is long enough for now, I look forward to reading more posts of yours.

Rick
 
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I am new to tube amps and have recently acquired a MC275ce. I am in the process of upgrading the tubes, and would like to know what the difference is between the Shuguang Kt88sc and their Kt88-98. And does anyone know about the Shuguang Kt88 Gold Aero? thanks.
 
We don't have personal experience with the Shuguang KT88SC which is OEM for Penta Labs and I don't know about Gold Aero either. Shuguang makes many many OEM brands and overtime I think no one but their own sales guy would know how many versions are available on the market :)

Sometimes the OEM tubes are simply a re-brand. I don't know the above two types is new design or not as we cannot distribute OEM brands.

We have KT88-98 which is an excellent budget tube. I think your amp tubes are the same as these, but may be labelled differently. Shuguang did provide the original KT88 tubes for McIntosh amps.

For upgrade KT88 tubes, we only have the Treasure KT88-Z which is a big step above the KT88-98 or other models that have been rolled to the market before. Of courser the price is also a big upgrade... you can certainly look into the Grade B which is less expensive than Grade A and still offer great sound and our full warranty.

I had an interesting talk with an amp manufacturer in China recently. They have been using Shuguang tubes for their amp for many years. The partial explanation of why recently many Shuguang tubes price has gone up so much - Shuguang used an inventory cost method to calculate their production cost. Many tube parts are from the 1960's old stock under China's government controlled economy so the parts were dirt cheap then. Now the old stock of parts are running out so when acquiring new parts, the production cost just skyrocketed. Talking about state-owned entity, their books should have been adjusted long time ago if they do run it like a for-profit business :) On the other hand, we as consumers have benefited from this book keeping oversight greatly indeed. Without Shuguang tubes, I doubt tube amps could be as common as today. Shuguang accounts for 30-40% of the whole world's vacuum tube output.

I hope this help a little bit.

Best,
Rachel
 
I am looking forward to reading your tube reviews, I do appreciate your efforts and it sounds like a long process.
I am new to tube amps..I sold my Edge NL12.1 solid state amp when I was offered a very nice Harmon Kardon Citation I pre-amp and matching Citation II amp. I needed some extra $$ for the home remodel I'm doing (complete renovation, changing layout of rooms, new walls, 100% new electrical and all new plumbing) I hope I don't regret selling the Edge amp.

After reading so much good about the Citation II, I decided to go with it.
I have already gotten all the Jim McShane upgrades/mods for the amp, but I still need to do the work, which pretty much replaces most of the old parts, all "new" NOS vintage Micanol yellow octal and 9 pin tube sockets, and adds a pair of switches (silver contacts) to switch from ultra linear (65 watts) to triode (35 watts).
I am looking to purchase another one of these amps and make a slight rewire to make both run as "mono" amps, @ around 130 watts ultra linear, 65 watts triode.

The recommended "affordable" power tubes for this amp are the Genalex Gold Lion KT88's which are just over $200 for a matched Quad.
When I seen the review of the Treasures, I was eager to find them...then I read the cost, just before I read your post..that is why I answered in the way I did..
The tubes would have to last longer than the standard or I could not afford to spend that much..or, if they are that special, I could use them only at special times.

Just for reference, my system consists of the following:

Speakers:
Green Mountain Audio "Continuum 3"

JL Audio Fathom F113 Sub woofers (2 @ 2500 watts each)

Pre-amp:
VAC CPA MKIII with "Signature" phono mods (sent to Kevin @ VAC and he went completely through it, upgraded everything possible, and brought it to the highest level he could..new tubes and not even 10 hours when I had to box it up because of remodel)

SACD/CD player:
Sony SCD-1

Turnables:
Technics SL-1000 (SP10 MKII with factory Obsidian plinth)
SP10MKII (2nd) for Slate plinth project
Goldring G99 (Lenco) waiting for plinth project
Various other Lenco's
Empire 208 waiting for project
Luxman PD-121 wanting to try in solid plinth

Reel to Reel:
Akai GX-646

Tuner:
Sansui TU-9900

Hm...I added more than I needed, I'm really missing my system..all boxed away... once I got started trying to remember what I have boxed away, I was also telling myself what I have :scratch2:

Well, this is long enough for now, I look forward to reading more posts of yours.

Rick

Wow Rick - you have lots of gear. I'm now at around 65 hours but I think that's enough. I'm going to start some swapping and critcal listening now with various music formats (genres and DVD-A's, SACD's, and regular CD's) and in both triode and UL mode. I'll work with KT-88's first - put the stock in for the 6SN7's and the 12AX7's and just see what I hear. Yeah, for that price they better last awhile. At the rate I'm going though they should last a long time :)
 
Well - I didn't do the exhaustive listening session I planned - didn't need to. I put my GF A-88 amp in UL mode, put on some PJ Ten Redux, and listened to the first 5 tracks with all the stock Shuguang tubes for the GF A-88. Music seemed very forward, Eddie Vedder sounded reproduced, not at all natural. In fact, I didn't like the vocals much at all. The highs, cymbals in Alive for example, were very loud and distracting from the rest of the music. The Guitar sounded harsh. I then powered the amp off, waited a few minutes, and swapped out the stock KT-88's with the Shuguang Treasures (tubes were really hot though let me tell you).

Listened to the same tracks again. Oh, forgot to mention, the A-88 is a manual bias amp, with the voltage recommended to be between .53 and .57 for the stock, and around .45 to .50 for the treasures. I set it to .55 for the stock (as that is how I had it before) and biased the Treasures to .50.

Ian told me that getting the Treasures (I also have the TJ Full Music 12AX7's but more on those later) would be more of an upgrade than a tube roll per say. Of course he's going to 'say' that, he's a salesman, right? And those tubes aren't cheap. I took it with a grain of salt.

Well, there was about a 5 minute delay as I mentioned I had to let the power drain from the amp and the tubes needed to cool a bit before I could take them out. Once I did the switch and started up TEN again - there was a definite difference. I wish I could have two amps running and just use a switch but even with a 5 minute delay I could hear it. The music had much more weight to it. Bass was a little less though, but it was heavier. Not sure if that makes sense, but that's what I picked up. Also the highs were much smoother with the treasures. With the stock tubes the highs were on the harsh side, which is saying a lot as I'm using Totem Hawks right now and they are not a forward/harsh speaker. Overall I would say the amp sounded richer, smoother, without losing any detail at all. Even the cymbals on Alive which were far too in your face with the stock tubes were not nearly as present but you could still hear them loud and clear.

I next swapped out the stock 6SN7's with my NOS 1958 Sylvinia black bottoms. This really 'lushed' it up I found. Again, I could hear a difference right away (note: Treasures stayed in). This sounded like I switched it over to Triode mode actually, bass was softer, but still present, cymbals were now hard to discern on Alive, in fact you had to now strain to hear them, but guitar sounded really sweet.

Last but not least, with the NOS 6S7N's and the Treasures still in, I swapped the 12AX7 Shuguang stock with the TJ Full Music 12AX7 tubes. Same 5 tracks again.

Detail is all back to where it should be, those TJ's sure woke up the 6S7N's, but the lushness did not leave. Cymbals were back though still not as 'there' as they were with the stock 6SN7's, but you didn't need to strain to hear them and they did not detract from the music at all.

This is the way I've been listening to this A-88 amp for the past 65 hours (which in real time is 5 months) and all I can say is each swap offered a definite improvement and I'm happy to hear it. I was worried I wouldn't hear anything.

Furthermore, Ian is 100% accurate when he told me this would be more of an upgrade than a tube roll per say. It really does sound like a different amp, a much better amp (and I'm not meaning to say it sounded like a slouch to begin with, but I realize why I felt the stock tubes sounded like they did when I first started this).

Now the scary news, I spent as much on all these tubes as I did on the original purchase price of this amp. Hard to believe but it's true. Was it worth it? IMO - yes, definitely. I now have an amp that cost me with the upgraded tubes approx $1500.00 that I would gladly put up against any other tube amp out there. Not saying it would beat them (the more expensive ones that is) but I'd bet it would very close. I don't think I could find a tube amp for $1500 that would beat this current setup.

Very happy indeed. IMO the treasures are well worth the expense.

Oh, btw - I've also tube rolled by B-283 and my Little Dot MKIV SE headphone amp. Neither tube roll, IMO, did a whole lot to the sound, maybe a little bit, but nothing that made me sit up and say "Whoa - what a difference", not like the tube rolls for the GF A-88 anyway. I'm not nearly as experienced in this stuff as a lot of you are so there may be better to the Treasures that I've never heard. I'd like to try the Gold Lion one day, but I'm in no rush at all after doing this little experiment. No wonder I haven't tried this earlier - been too busy enjoying what I already had :D
 
try the Raytheon 6sn7 tall boy black plates with large halo getter-you will completely forget the Sylvanias were even at the dance.
 
I never heard the chinese tubes in this thread but my JJ KT88's are amazing! they dont run too hot, the bass is best I have heard so far and they image wonderfully. For the pre-amp section I use 2 electro-harmonix gold lions and one Mullard. I may change that in the future but I like them for now.

My amp is a Tri-TRV 88SER

from Japan.

here it is..https://www.youtube.com/watch?v=Xdr6NW2it_A&list=UU9MEDgTxd3sYrK5SPNwcAfQ

I'm a fan of JJ kt88 as well. Nice looking amp you have. Was that model made for Triode by Line Magnetic?

cubdog
 
I'm a fan of JJ kt88 as well. Nice looking amp you have. Was that model made for Triode by Line Magnetic?

cubdog

I'm curious (as well as profoundly "tube ignorant"), how might these JJ KT88 compare to the Russian made Genalex Gold Lion KT88 reissues of recent years? I have those in use now, and love them. If there are KT 88s out there with superior sonics, I would be in hot pursuit of them.
 
I'm curious (as well as profoundly "tube ignorant"), how might these JJ KT88 compare to the Russian made Genalex Gold Lion KT88 reissues of recent years? I have those in use now, and love them. If there are KT 88s out there with superior sonics, I would be in hot pursuit of them.

I'm with you as far as tube ignorance goes. In my case I needed a replacement quad of KT88 shortly after I bought my Shuguang amp. I received it with two defective Psvanne tubes and need something fast. I did a minimal amount of research and settled on a quad of blue glass JJs. Admittedly I have limited experience with KT88 but I've been very happy with these so far. I run them 8-10 hours a day most every day. To my ear they sound great and I've had no problem with them.

cubdog
 
I bought a pair here recently, using for about two months now, no problems.
sound great, detailed, good range, smooth. Could not ask for more.
Look good too.
 
I've had 1 or 4 fail. Maybe 250 hours on it, at the most. Problem is it went while playing, not turning on. So it took out some parts on an audio research amp. And you have to use a matched pair when replacing so you have that problem where 1 failure is actually a double cost.

I like the sound of them but factoring in failure rate risk--and total costs incurred--changes things.
 
I've had 1 or 4 fail. Maybe 250 hours on it, at the most. Problem is it went while playing, not turning on. So it took out some parts on an audio research amp. And you have to use a matched pair when replacing so you have that problem where 1 failure is actually a double cost.

I like the sound of them but factoring in failure rate risk--and total costs incurred--changes things.

If you bought the KT88 tube from Grant Fidelity and still under warranty, you can contact us through website to arrange ship the single one back - we can match a new one to it to make it a pair again. If no longer under warranty, we can still help you likely with better pricing than full retail as additional service to existing customer.

Happy Listening.
Rachel @ Grant Fidelity
 
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