I'm mainly creating this thread so that the Light Harmonic Geek Pulse thread doesn't get too flooded with impressions about the Geek LPS by itself. My sonic impressions of the Geek LPS4: I've been doing some testing between the Geek Out on my MacBook Pro and the Geek Out with the Geek LPS4. Between the two connection options, the LPS definitely improves the instrument separation and the overall blackness of the background, which improves the imaging. Another noticeable difference I hear is an improved bass extension with bass that's a little more present, which may give the sense of better dynamics in my music. Likewise, when powering the STAX SRM-252S amplifier with the LPS (Geek Out is connected to my MacBook and not the LPS), I notice a similar effect: the background becomes blacker, instrument separation and thus imaging are improved, and bass response becomes more noticeable. I plan to do some more testing later to see if the volume changes between powering options for some reason, but in the mean time, here's Something New for ya. A free FLAC/ALAC download from his Bandcamp page: http://kubbi.bandcamp.com/album/something-new My complaints about the Geek LPS4: It doesn't power the Geek Out if the GO is connected to the LPS when turning on the LPS It produces a loud buzzing sound if I connect a USB DAC (or any USB device that draws power) from its USB output in addition to powering an external amplifier I thought problem #2 was due to a grounding loop between the USB output and 12 VDC outputs, but that might not be the case since the volume of the buzzing increases with the volume level, and thus power drawn.