A few upgrades for me...
I bought a monitor stand for the amp. The dimensions are perfect for the MK VI! My headphone setup is connected to my computer and I'm a hard core gamer. My monitor is a behemoth (GDM FW900) and I wanted some more space to put stuff on my desk. The stand only costs $21 at staples. I bought a bunch of furniture, etc last week cause they were (perhaps still are) running a nice promo - $75 off $290 coupon with free next day shipping. Here's a link
to the stand. It has holes so the amp is getting proper ventilation. No idea if it's helping with damping. It does have some rubber feeting of some sort. I don't really care.
My advice for anyone thinking about tube rolling. Aim for the top! I'm not to sure about power tubes since I've only the 5998s. I think they are very nice, and from what I've read, they are the best 6AS7 tubes (suppose to be the same as the 421A, which takes the top spot I believe). I bought my quads matched for $140, $190, but I've seen them on ebay for under $100 (dunno if matched though). I spent the weekend listening to the ECC35 and they sounded spectacular. My favorite tubes prior to hearing them were the VT229 Tungsol. I like them a lot because they were very rich and musical, although I felt the Brimar CV1985 had the edge on detail. The ECC35 is just a nice combo of richness and detail. I've never heard the K1000 sound so damn sexy until I got the ECC35s.
Before, I thought the K1000 was lacking in body (CV1985). I'd have the K1000 angles closer to my ears cause otherwise, the bass would be a bit thin. With the ECC35 I have them angled just about all the way out, sometimes all the way out, and I still get nice bass. Haven't tried Senns with the ECC35, but I'm guessing I'll be just as happy. The ECC35 is also more forgiving compared to the CV 1985. Helps with silibance.
I think I'm done with amp and dac upgrades for say 3-5 years. Everything else till then is just experimentation or side steps. My dac, Stello DA100 Sig... Hmmm... I'm inclined to say it's on the warm side, but can be too revealing (or harsh) at times. I don't have much experience with dacs. My only reference points are the emu1212m and pico with dac. They both are more neutral, lean towards the analytical sound, and still reveal harshness. It's only about maybe 5-10% of my collection that may suffer from some crappy silibance or recording. I have about 2tb of music and a good amount of it isn't main steam, e.g., doujin from comiket. I still dont know what to think about it. Is this the way it should sound (the way it was recorded), or is my DAC inferior somehow? My hunch is that it's just the recording.
Stello DA 100 Sig -> LD MK VI (Tung Sol 5998 + Adzam ECC35) -> K1000. I'm very happy with this setup, just wish some songs were more forgiving. I'm still going to try to find something for my GS1000 because I think they have a lot of potential. At the moment, this setup is murdering everything else I got. HD 800 is next for the amp, just gotta source a cable for it. I guess it'll be a few months from now.
ECC35 - highly recommended. I will be grabbing some more pairs when I get the chance.