Got my Vali today (#365). I have it stacked right above Magni to make some comparisons. Looking through the holes of the vent, it appears that both tubes are in flat position. The initial ringing takes about 1 minute to go away. After that, changing the volume, moving the headphone cord, typing, moving the mouse all do not cause further ringing. Turning the volume all the way to 100% does not cause noise or static. The volume control is smoother than the Magni's when I got it initially and it doesn't cause static at certain volume levels like the Magni initially, even though it eventually went away.
Listening to norah jones' come away with me album right now with the setup in my sig, I first noticed how tight and more controlled the bass is. The bass isn't exactly more prominent or heavy, but it definitely sounds better. I think the sound stage is *slightly* closer, as though I am in a smaller studio recording room listening to a live performance. I never heard the "watery" sound of tubes before, but I think there's a very tiny addition of reverb, smoothing the sounds to flow almost like a gentle stream. Guitars sounds MUCH better somehow, perhaps due to this watery sensation or a tiny bit of reverb. With the entire sound warming, I think the treble isn't as clear. Certain parts of songs where there's electric guitar hitting higher notes, those aren't as clear as before and doesn't strike out as much among the other instruments playing. I think it's less analytical than the Magni, but less harsh on your ears. I wouldn't say it's "better" than the Magni, more of a choice of what type of amp you want. However, I do like it more than the Magni with my HD650. I wish I can compare it to the Bottlehead Crack though, and would absolutely love to hear that pairing with my HD650.