Similar timbre and transient presentation to Fulla 2, but more powerful, more robust. Perhaps a bit warmer, a bit bassier. I believe the design is similar, but with higher voltage rails and maybe tweaked power supply. While the Fulla 2 only requires one USB connected (shared power and data) for it to work, but Hel requires both. I have both Hel USBs plugged into the USB ports of my laptop, thus not requiring the use of the wall outlet adapter. Note that the Fulla 2 requires it's second USB (power only) connected for best sound quality anyway. Technically, other than more slam, not sure if more plankton than Fulla 2. Maybe 1%. It's certainly not a DNA Starlett. For those with full sized headphones looking for a bit more oomph than from Fulla 2, the Hel certainly provides it. There is a microphone input with adjustable trim included. I will test this later. Does anyone have suggestions for a good electret microphone? I will give away my Fulla 2 to a coworker and have the Hel in my bag going forward. I've mostly been using transportable gear lately because I will work at several times spots in a week. Headphones are the lightweight but trusty Sony MA900, and ZMF Verite (if I can lock myself into a room on days were I don't have conference calls). Will take a few measurements if I can find the time.