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Best KT88s (specifically for VAC Auricle Musiblocs)

I'm using a KT88 based amp for the first time - the VAC Auricle Musicblocs. I just had them serviced but one of the cheap Svetlanas blew, probably from my biasing it too high, and its been replaced by a used Genalex Gold Lion for the moment. The amps sound very good as it is, but I'd like to get the best out of them with a good matched Quad of something decent.

Ideally I would like a little more mid-range luxury and presence without sacrificing too much bass control. However lower bass is not so much of an issue because my speakers have powered subs with an active crossover (Vaughan Cabernet One).

I'm in the UK, and valve selection here is a bit limited. Nobody seems to have Svetlana Winged Cs anymore, and I've read reports of dubious quality in the later batches. Genelex Gold Lion are easy to get from good dealers who can match and measure, so that is the obvious choice. But would I be better of with some Chinese valves such as the Shuguang KT88-98? Are they going to be a bit warmer in sound to the Genelex?

I've read great reports about the Psvane KT88 T2 but they are very expensive. Also the Shuguang Treasures. The riskiest option is to buy these from Mable Audio in China, who have them up for a good price:

http://www.mableaudio.com/en/

From what I have read Kevin Hayes supplied the Auricles with the Shuguang KT88-98. These are very affordable, but I suspect that Kevin only supplies selected ones. 

I could also buy from the US, and I'd appreciate any recommendations for the best source.


andreweast
jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
I'm pretty sure that Kevin will nix the idea of KT-120's and KT-150's.
His amps are pretty selective with only KT-88's as far as I know. VAC doesn't even recommend trying any 6550's.

Yes, I am using the Psvane KT-88 TII's, and I only slightly prefer them over the Gold Lions. Just a tad more relaxed sounding.
I found bigger differences changing preamp and driver tubes.
andreweast OP
30 posts
 
Kevin has just told me that the Gold Lions might be the best idea to get what I'm looking for, and that is certainly the easiest option for me.

I take your point that the input valves are likely to make more difference, but I can't get much warmer than my Mullard CV4003. Pre-amp valves I can work on.

I suspect the change I'm looking for may not come with small things like valve changes, I've just switched speakers from my Vaughn Cabernet 1 to my Harbeth SHL5Plus. There's certainly no lack of warmth with the Harbeths, as you'd expect. It might be that I will need a differnet power amp to get a warmer and more intimate sound with the Vaughns, but then I'd risk losing the amazing dynamics. Always a tricky balancing act. 


jond's avatar
jond
3,400 posts
 
If you're looking for more warmth try an amp that uses EL34's and get a set of Gold Lion KT-77's. It's a great sounding tube that was far better than PSvane, not the regular EL34 I tried a pricey vintage PSvane Philips reproduction tube, great packaging but they sounded bright compared to the GL KT-77s. I don't have a specific amp to recommend, mine is a custom Deja Vu Audio amp, but there are tons of good EL-34 amps on the market. Happy listening!
bradf's avatar
bradf
288 posts
 
This doesn't really answer your question regarding best KT 88, but I thought you may find some interest in it. I too am considering replacement of power tubes in both my Ars Sonus Filarmonia, and Primaluna P5.
I have been researching Psvane EL34, and KT 120 (including Black treasures)
I have a spare set of JJ E34L quad for my Filarmonia that I substituted for the Gold Lion KT88 in My Primaluna 5.
A truly unbelievable improvement. It is the most difference / improvement I have ever experienced in a power tube and I have tried a number Including the GL KT 77 and NOS GE 6550. I am pretty surprised how well this $14.00 US dollar sounds. You may give it a try. There available at The Tube Depot in quads and for a couple bucks a piece you can get them burned-in. Just want to clarify that these are the E34L's and not the EL34's. Also came across a couple of vendors selling NOS Siemens EL34 https://www.tubedepot.com/products/rft-made-siemens-el34
http://www.tubeaudiostore.com/elpremgrad.html.
http://www.nosvacuumtubes.net/product-category/power-tubes/power-tubes-6550/
The above 3 links/stores have several type of NOS power tubes, including NOS Mullard EL34 (expensive) and Amperex EL34, and others
You may find the new production Telefunkene Black Diamond EL34 tubes of interest. In addition to EL34's they are also producing 6550's and KT88's.
With the exception of the JJ E34L tube, I can't help you regarding the sound of the above referenced NOS tubes, that's something I am trying to gather info on.
Any one reading this, who has tried any of the above NOS tubes or the new production Telefunkene Black Diamond tubes your input would be helpful. 
xti16
1,495 posts
 
If you’re considering KT90’s look for the Ei KT90 Type II. They don’t come up often but when they do they are a bargain IMO. Tough as nails with mids similar to El34’s but with more sparkly highs and tighter lows. I found the sound stage improved by getting wider.

As far as KT88’s I have the winged ’C’ SED KT88’s and they have a lot more bass than either the Ei KT 90 or Gold Lion (Russian reissue) KT88’s (which I also have). The original Gec KT88’s are very linear sounding. Extremely good and almost as good as the EAT KT88’s. But those come with a hefty window sticker.

That said I had an Octave V70se and later a V110. A lot will depend on the topology of your amp. More important IMO is the speakers. If you’re looking for a warmer sound the SED or GL KT88 is the ticket. If you’re looking for more detail and linear the Gec or EAT KT88 is the direction you want to go. Never tried any of the Svetlana or Shuguang tubes. Personally I hated the KT120's. To me they never sounded coherent like any of the tubes I have.
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