I have the Valve Art 274Bs that came with my Torii Mk2 (modified to run these).  I was noticing a bit of sibilance, decided to try the NOS RCA 5U4Gs that I have, and the issue disappeared.  They are relatively new, so it could be that they aren't burned in yet, but wondering if anyone has compared the Valve Arts to the Shuguangs?  

- Michael

Sorry, not yet. I had hoped to do so this weekend, but I just ran out of time.

Yes, I'm running these for the nonce in my Torii Mk II and Mk III (cryo'd in the III) and no modification was necessary. They're more like 5U4G than other 274Bs.

I finally got a chance to try the Preferred Shuguang 274B that I ordered from The Tube Store, and compare them to the Philips 5R4GYS I obtained from Upscale Audio.

I tried each in my recently returned Ultra, and in my front side Torii. It's a bit of a toss-up in the Ultra, where I perceive the soundstage to be a bit wider, and the background blacker, but in the Torii, the Philips exhibits better and tighter mid-bass and bass control. On double bass, the difference is not subtle. For half the price, though, the Shuguang 274B is a bargain.

I have not yet tried the ValveArt 274B from Cryoset, but I am going to. As I understand it, it is the same maker/make as the Shuguang. Getting it cryo'ed from Cryoset even cheaper is just sweet.

Gopher,

I think we are probably talking about the same tube with the "preferred" testing done at thetubestore, and cryo treatment done at cryoset being special treatment, but on the same basic tube. If you compare pics of these in the link from Pale Rider's post just above your recent post http://www.tubeman.com/item524.htm

and these:

http://www.cryoset.com/catalog/product_info.php?products_id=364&osCsid=f089cffda...

and those like yours: http://www.thetubestore.com/Tubes/5U4-Tube-Types/Preferred-Series-274B-5U4G

they all seem to be fundamentally the same tube. The Shuguang 5U4G-ST (Rubys) look and sound different...several on this forum not liking it much. It is a shorter and narrower coke bottle shape with one bottom getter as opposed to the wider, taller 274B that has two bottom getters.

Just for clarification for others that might look at this, does this seem about right to you?

They're the best quality tube I've used yet from Valve Art. But. . .they're too forward and a bit bright for my tastes. The cryo'd I like a bit better than the non-cryo'd.

I find it hard to go wrong with old RCA rectifiers, I'm using a pair of 'forties 5U4G that I bought from Mike (tgarden) and they are just right for me.

I'm sure there are even better such as the type you are using, but I'm at a point now where I am just enjoying the music and everything is sounding very good and I'm just not rolling!

I'm not really a Tung-Sol fan, so I don't wonder about those. I'm mildly curious about the RCAs but sticking with what I have for now.