Have you seen Archimago's measurements? HS01 does a good job of lowering noise and harmonic distortion.Any more impressions on the HS01? I'm thinking of ordering one. Ground loops aren't my problem, but I get PC electrical noise that the E30 picks up over USB. I'm using my USB ports for keyboard, mouse, wifi receiver, the E30, and in the front an external hd, sometimes a game controller, so it's a bit busy.
MEASUREMENTS: Topping HS01 - USB 2.0 Isolator & Ground Loop Eliminator (and a listen to Santana's "Blessings and Miracles")
A blog for audiophiles about more objective topics. Measurements of audio gear. Reasonable, realistic, no snakeoil assessment of sound, and equipment.
archimago.blogspot.com
I used the very cheap ADUM3160 on the E30. Although I don't hear an audible ground loop in my system without it. It is measurable can reducing noise. Unlike HS01, harmonic distortion does not change with ADUM3160. It's ok if only listening to CD Quality music because the speed only 12mbps.
*sorry for the bad graph because of the ADC I'm using.