Interesting Level descriptions, to me they make sense.
I think I just transitioned to level 4 after upgrading my Lampizator GoldenGate to GG3 with the new Engine11P, volume control and USB. The new USB requires a USB cable with a 5 volt leg. I had to send my Sinope out to add the leg. While the cable was out I used the ethernet output from an Innuos Statement thru an UltraRendu and used a Network Acoustics USB to an Antipodes S20 and then SPDIF out to the Lampizator.
Immediately I noticed the PRaT I was missing with USB. There was some loss of sound quality I attribute to the NA USB relative to the Sinope. When the Sinope came back I still preferred the Ethernet output of the statement to the USB with the Sinope. Now I put the Sinope between the UltraRendu and S20.
As the Statement outputs both USB and Ethernet together I can set the same music to play at the same time with the InnuOS Sense and switch between them real time. The PRaT is hard to describe but very easy to hear when its right. There is an obvious time smear to the USB output when heard together.
I can remove the S20 and use the USB output of the UltraRendu to the Lampizator and the PRaT improvement is still obvious so it seems to me it is the difference between the Statements USB and Ethernet outputs.
I don't know if it is an issue with the Statements USB or with USB relative to Ethernet as a carrier for digital information.
I believe in PRaT, to me it changes the sound to a relaxed more analog feeling and the Rhythm and Pace immediately reminds me of what I prefer when listening to LP's.