I think you are on it with the Isotek/Esoteric CD as is...better quiet all night than without and probably considerably better than music since it is designed specifically for fast burnin, covering a huge range of sounds and attacks to flex the system. When I come home after several hours of it playing, the sound seems more improved than several hours of music by quite a bit. Subjective I know, but my impression. I just assume that using it (or music) at various volumes would work the tubes and all else differently, and ultimately better with variety of power and push. But you do what you can.

Looks like the tube companies or vendors could come up with a good, efficient  burnin system and charge a premium for ready to go tubes for us freaks with very revealing systems.

An excellent point indeed. These are the only tube amps I have had since I was a kid, so I take the ease of rolling for granted. Especially with new tubes or a new piece of gear, I will roll every day at times, and sometimes several times in a day in looking for that just right synergy/signature. So easy!

My JJ's just arrived...

I quickly popped them in and I agree that they are very good indeed. Nice and "tubey".

Any consensus on time for break-in? They sound really tight (not open at all) on the top end, but everything else is wonderful.

Thanks Lon.

Hoping Steve will maybe step in here and answer that one.

My take is that that besides some minor differences in operating parameters, the big difference lies in that there's some beam forming plates that take the place of that 3rd grid on the El-34.

In my (tiny brain's) opinion, the mod should help in close to the same fashion.  

Also

Well, mine seemed to stop changing yesterday after running them about 15 hours a day since they arrived. But hey i'll be happy if they get more dynamic, but I still have my doubts.

I agree, I don't think Steve would send out tubes with this amp that didn't take advantage fo the mod.

I put the Winged Cs back in for comparison. I think the Winged Cs will stay in for a while. Ironically the Cs make the Torii sound less like a tube amp, but fantastic. The bass is better. The midrange is so open it's as if you can see way deeply into the music, less so with the JJs. And "faster" and a touch more dynamic than the JJs. Both are great choices, and I can see why given that Cs are harder to find these days Steve has gone with the JJs stock.

I'll use these Cs til they're gone and then go back to the JJs.

Winged Cs have gone up but here are some.

http://www.tubesandmore.com/
http://thetubestore.com/el341.html

Don't know why the Antique Electronic Supply (tubes and more) link is not associated with the page i got it from with the Winged Cs, but they have it for about 145/quad.

After making that comparison I haven't been completely happy with the JJs. Thanks to a sale of power cords to Greg and Greg (thanks guys, cords are packaged and about to go in the mail) I ordered a "burned in for stability" set from Antique Electronic Supply.