6 days in now. Got to play with some tubes. I put the stock ones back in to break in. At first it sounded pretty good, but then it was clear the magic was gone. It still sounded technically good. Still a big improvement. Like literally right in the middle of my old Pontus compared to new Lampi with my tubes. Putting my RCA rectifier back in was clearly better. Not drastic, but nothing I want to give up. The Sylvania bad bouys made the most difference... the magic was back. Incredible. Then I changed out the 12BH7s for my 12AU7 Mazdas... magic magnified!
With my LTA Z40 Int, I played around with tubes. It came with all really good NOS Mullards. Even selects. Different brands of course, but Mullards. Mullard EL-34s that will never leave. RCA black plates for Pre, and Mulard AX7s and Mullard AU7s input/drivers. I swapped out the Amperex branded Mullard AX7s for Telefunken AX7s... just holy crap. Next level stuff. I got some Tele AU7s for 4 pairs... nope, too much of a good thing. Lost that awesome Mullard low end. I got some RCA clear tops. I swapped every imaginable combination and mix. The RCAs were good all-rounders for Pre. I could never give up what Mullard gives, and I could never give up what the Tele AXs did... I was done.
Then Jessee suggested I try the Mazdas for pre.... I bought spares. I agree with him they are much better RCAs. But it is really weird what they do... they like amplify how good Mullards and Teles are. Sure, they allow more through to them, but again after swapping around.. I can't say they have a "sound", they just make Mullards way better, and Teles pure magic.
I said all that to say... swapping everything I have did not change the voice of the DAC. Nothing is more low end centered/high end centered. They all sound the same all around good from the bottom to the top. It is not like how I can play with voicing my Z40 and make big changes in the sound of the FR. My NOS tube just simply sounded much better in every respect, bass, warm mids, trebble, space, air, resolution.... Clearly. But when I put the Mazdas in... all of that doubled. Same thing. It didn't change the character, just made everything even better.
My thinking is I do not want to "voice' my DAC. I already voiced my amp. I want my DAC to be neutral so to speak. It absolutely is. Plust I don't have the same options with ALL the different brands to change sound. All the good stuff is generally US made RCA/SYL,Tung/GE. I could try my other AU7s instead of the Mazdas but don't see the point. (you know I will). It will skew things in that direction. Right now, for what I want for my preferences and what I listen to... I am still just floored by what this DAC does. I lost 2 hrs today I did not have to lose just flipping thru playlists... I just could not stop... jaw dropping.