if you want to blow your mind...try some NOS Sylvania 6SN7W's ....you'll think you bought a new amp (a better one to boot)
It's good there are now two kinds of high-quality 6SN7s from New Sensor within a few dollars of each other. I have NOS Raytheon & Sylvania chrome tops to compare to EH 6SN7 & yes the NOS are better. But the EH are quite good. In many instances the considerable expenditure of rolling NOS tubes might be more wisely committed to circuitry mods that produce greater returns than tube rolling.
I know - that's what I keep hearing. I'm just trying to find what I like in the current-production world first - NOS is expensive and you never know what you're actually getting from the seller. I'm sure I'll succumb to the NOS bug sooner or later.
By the way, I actually like the dynamics of the 6SN7EH a lot, it just sounds bright/harsh in the highs in my system. The Tung-Sol eliminates some of that brightness, while retaining the dynamics; at least it does in my system.
I also tried the Chinese Sino/Shuguang 6SN7. It is much warmer than the EH or the TS, but the whole presentation is less focused and the dynamics are nowhere near as good. Too big of a tradeoff in my opinion.
One thing I forgot to mention - it seems that the TS like to be driven a little harder than the EH. When I first swapped in the TS, they sounded light in the bass and lower mids. The Chenin is very adjustable, though, so I moved the gain switches behind the 6SN7s from low to medium, and turned down the master level control on the back of the pre one notch - voila, the bass and mids were at least as good as the EH now, with the highs still much more accurate, and the volume control still had the same range. Gotta love flexibility!
I did a similar trial w/ my AtmaSphers MA1s. I had all EH 6SN7s in them for about a year or more. I replaced the 3 middle tubes (considered the most critical, sonically)with TS Reissues. My first impression after letting them burn in for about 20 hours was that they were much more dynamic and tighter in the bass. I began to wonder, though, how much of the effect was due tot comparing them to tubes that had many more hours on them. So I bought some new EH tubes, and tried them out. I put the new EH in one amp, left the TS in the other, and played them for a few weeks before listening cpomparitively. What I heard was that the 2 tube types were extremeely similar. I could not tell much, if any difference, although I desperately wanted to. If anything, I thought the TS were slightly more forward in the midrange, which in my system was not a good thing. I think I put the old EH in for a bit, and concluded that the new tubes sounded very much like the old EH; in other words, the initial improvement I heard with the new TS wore off in rather short order with use. I wanted to spend some more time with these comparisons, since I bought the new EH just for this purpose, but I got distracted with chewcking out some new source components. Ultimately, I got bored with trying to hear the differences between the tubes, because they seemed so slight, once they all had some serious time on them. I would like to go back and compare again, but I'm sick of listening to equipment, and have been enjoying listening to music for a while. I'd love to hear any other opinions on this, especially after your tubes burn in for a while Ait. It's pretty cool that you can vary the gain on your input tubes like that to tailor the sound.
Hi seems like some of this is system dependent.
In my BAT VK75SE (now 150SE) I had RCA 6sn7's. softer on top, little more real, but lost the dynamics and punch and texture of the russian 6h8c's. I ran the RCA's for a year before I went back to the 6h8c's.
Doug: what are you running in your 75SE right now? I'm due soon for a retube, and can't decide on the 6h8c's or the EH's or Tung sols...
Concerning the Sylvania 6SN7W: Of the two types(short/Tall, with either metal or plastic base) The tall have exquisite sound stage, imaging, dynamics in all octaves and transparency. The short are equals everywhere, but- have a tremedous amount of energy in the upper freq.s, and- If your system is at all bright: they will singe your ear hairs. The other Holy Grail of the 6SN7 family is the TungSol 6SN7GT round plate, bottom getter(not the mouse ear)from the 40's. Everything the Sylvania has with a slightly deeper sound stage. That's what I get when using them in my Carys anyway. Another tube that is very close in sound to these is the Syvania CHS/6SN7GT/VT-231 bottom getter from the 40's. Just a little less sound stage depth, but the same liquidity and transparency(much less expensive). Another less expensive entry to NOS tubes in this family is the Ken-Rad VT231 bottom getter from the 40's. I've only included the tubes that exhibit the greatest transparency/least coloration. Yes- It's hard to find these tubes in closely matched pairs and they are expensive, BUT- as stated: They will improve your system like an equipment upgrade, and are worth the time and every dime! The Sylvania 6SN7W was the only top-getter tube that I found worthwhile.
IMHO, if you are using new production 6sn7's in any critical spots in your audio gear, you really don't know how good your system can sound until you try the vintage 6sn7's, i.e., the tung sol round plate, the Sylvania 6sn7w, or even the more reasonably priced RCA 6sn7GT grey glass. All of these are better than any new production 6sn7's. However, if you are using the new tubes in circuits that do not critical effect sound they might suffice.
jfrech, not sure if it's me you're asking, but in the input section of the 75SE I'm using 6SN7EH, Tung Sol reissue 6L6, and 6H30pi/EB. The new Tung Sol 6L6 has great tone, and IME there is only a slight gain in this unit with NOS 6H30DR.
I noticed you've added some nice cables to your system. I strongly suggest you consider replacing the two-foot lengths of $.40/ft IC cable used inside the 150SE.
sorry Dave on your name !
I guess I'll order (gulp) 12 of the EH 6sn7's and I will try the Tung Sol 6v6's. I think my 6h30's a good a little longer, using a 2 yr old set of dr's from when I retubed my 51se last. I wish I would have bought a pile of the DR's then. But I agree with you, at these prices, maybe I can live with the pi/eb's.
I have been reading your posts on the 75se mods. I do feel squeemish buying this expensive interconnect/power cords then open the covers on some gear. Also, I have that same "cable" connecting both halfs of my amps internally as part of the bridging circuit. Using what looks like automotive type plastic connectors via another 6 inches or so of wire.
How hard is the rewire job? BTW, What part of the world do you live in?
Jfrech, recabling of the intrachassic IC requires only basic soldering skills. I used a three-twist of Audio Consulting 24awg silver wire in natural cotton sleeves-- about $50 per chassis. You can use any good IC that isn't too thick to route down center between the PCBs. You would also benefit by hardwiring the master/slave connection that converts stereo to monoblock. Free free to email if you want more info. I'm in the NE. There's a sleeping giant in there...