Had an interesting experience. I messed up my I/V opamps, so I didn't have any for a week while I waited for a few new ones to arrive and was forced to use the tube output. I used a Heath/Mullard from the early 60s that was really nice. I started really liking the sound. Especially combined with a pair of 49990s for the I/V that I accidently stumbled on from a local guy. So when I got the singles back, I tried them with all kinds of different combinations - I have two types of 2604s, 1028s, 797 duals, and 49990 duals as well as the stock 5532s. For the output stage, I have 797s, 49990s and the stock 5534s. I was really torn. I liked the detail and clarity of the SS with the tube removed (removing the tube obviously helps, as everyone agrees, by reducing the power load.) I think my favorite combination was the 2604s with the 49990 output, followed by the 49990 duals with the 5534 output.
But regardless, this all changed completely when I received by Siemens early 60s NOS silver-plate. My GOD. The 2604 had too much bass and was a bit muddy, the 797s were too dry, but the 49990 duals with the Siemens chrome/silver plate was HEAVEN. All this air, rich, tight bass the welled up, and this liquid, gorgeous presence that just made the whole thing glow.
I was actually really annoyed. Because I was committed to using the SS without a tube, for the precise reason that that would have meant that there was one less thing the new tube dac+ did better. See, I have the original tube dac. I'm getting the volume bypassed locally, so that's a big part of the new version's appeal. I've gotten a MDHT USBridge with a direct coax-coax link from viablue that I'm certain is very close to or better than the new usb imput. So the final thing was the updated power supply. And if I wasn't using the tube, I could convince myself that that didn't really matter much either.
Unfortunately, in test after test, day after day, for several days now, I consistently prefer the silverplate. I get annoyed with myself and swear I must be mistaking something, and tear it all apart again, but the difference is obvious to me. The bass is better, the midrange is better, the treble is better, the soundstage is better, everything is just nicer and I don't hear any obvious tradeoffs. I'm running the 49990 duals for the I/V, with nothing in the 7/8 SS output stage and the Siemens silverplate. Probably because the JH13s are dark, and my TWcu cable is dark as well, this combo really brings everything into perfection. I don't know if I just got lucky on the tube or what, but after like 20 different variations, I'm now totally happy with this and may actually be quitting head-fi for a while to concentrate on LISTENING.
