Regarding Soul: A friend of mine here in Los Angeles just took delivery of s/n 0001/0002 Soul speakers. His are Superfly. This speaker is better than a Druid Mk 4-08 in every way, for less cash. The FRD is below the supertweeter so that it would fit in the tapered cabinet while sticking to Zu's preference for packaging their sound in a 1 s.f. footprint. Zu extended what they learned in designing and building Essence -- their first full-Griewe implementation -- to a more economical structure and build process while further improving the Griewe model in practice. This speaker upends traditional notions of how to allocate system resources. It truly takes full advantage of high performance amplification and accentuates the reality that a system with Zu speakers moves the fulcrum for fidelity to the power amps. You'll see Soul Superfly systems with power amps that cost 5X and the resulting sound will be entirely legitimate. In fact, I'll go so far as to say that $9500 worth of the right power amplification on $2600 of Soul Superfly will sound better than a good budget amp on Definitions.
Phil