Sorry to interrupt the philosophizing, rationalizations, and general banter; but if I may, I’ll add something about the subject matter of the thread title
One month ago, I received the Horizon dac which was the unit auditioned by the OP and compared against the dcs unit. Included we’re the tubes used for the comparison. I can offer that 4 additional weeks of break in along with changes in the tube set have made significant improvement in the performance of the unit.
Upon receipt I inserted the supplied tubes and listened to this configuration for a couple days before rolling my own tubes in.
Supplied tubes:
EML 274b mesh rectifier
Psvane blue ball 6sn7
KR KT 88
Tung-Sol KT170
Rolling to either the csf 5687 or Tungsol VT-99 from the blue balls made an immediate improvement to resolution, depth, and naturalness. Each in its own way.
The EML274b is just fuzzy sounding, although dynamics were decent.
Replaced with the RK 5u4g to tighten things up. However, it can go too far. It is not a good pairing with the KT170. The additive result is a scream in the upper mids. Just too much. I suspect the Tak 274b will be better overall as the RK’s edginess can be a detriment.
Either KT’s can work for me, depending on the other tubes used.
Additional time has allowed the Horizon to open up and smooth out. Resolution and dynamics are first rate now.
So this is really just a young Horizon vs. mature Horizon comparison along with an opinion on tube choices.
Point is, the Horizon as auditioned by pk-LA was not in top form, but it is now.