Tag: KT88-Z / KT88-T/TII

Treasure KT88-Z: ‘smooth clean highs, strong deep bass and all the other’

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

 

‘IMO, the Treasures well worth the expenses’

by past customer KptKrunch – owner of Grant Fidelity A-88 tube amp:

Original post on audiokarma.org:

http://www.audiokarma.org/forums/showthread.php?t=241929

“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.”

Treasure KT88-Z: ‘I found the best combination’

From Greg L., owner of Grant Fidelity A348 tube amp and KT88 treasure tubes…. he found a great combination in his setup and I am sharing his secret with you! 🙂

 

Hi Ian/Rachel,

I’ve been doing some tube rolling here for a couple of days and I have arrived at a combination of

NOS and your KT88 Treasure tubes that really, really, sing!

My current and best tube audio setup is comprised of:

AMP

  • KT88 Treasures
  • NOS Telefunken 12AX7’s
  • NOS Sylvania 6SN7GTA Chrome Domes (short early 1950’s version)
  • CD Player
  • NOS Mullard 12AU7’s
  • NOS Siemens 12AU7’s (alternate)

Speakers

1979 Klipsch Cornwall I’s

The short Sylvania 6SN7’s are even better sounding then my Tungsol Mouse Ear tubes which you heard briefly before they reached optimum operating temperature last week.

Regards,

Greg

Treasure KT88-Z: ‘what a nice upgrade’

from customer Mike G. by email:

Hi Rachel,

Wow.  What a nice upgrade.  They only have 8 hours on them and I am blown away by the lack of grain in the midrange, soundstage layering, and bass impact these Treasures have compared to the Genalex reissues.  Its not even close.

Thanks,

Mike G.