My goal was to redo my entire system with first class components and be done with it. The system is located in a real-world living environment (as apposed to a dedicated listening room) with mostly off-axis seating. My priority was a system that had rich tone and "presence," was full-range, was not associated with listening fatigue, and could fill a very large space and still sound good at low volumes with all types of music; typical audiophile priorities were secondary. I started with the ZuAudio Definition 1.5s, but upgraded from the MK1.5s to the MK2s (when the MK2s were announced during my trial period) and eventually to the Definition MK4s. (Sean Casey tuned the MK4s to be flat to 16Hz; the output curves in the ZuAudio specs and product manual come from my living room.) This was my first foray not only into high-efficiency speakers, but also into tube electronics. I started with an EAR 859 amplifier that was replaced with a Yamamoto A-08s and then a Deja Vu 45/2a3 SET. I also started with an EAR Acute CDP. However, I discovered the Ancient Audio Lektor Prime CDP in Krakow when visiting Poland in 2008. And, eventually, I had an Ancient Audio Integra 300b SET made to match the Lektor Prime. The Integra 300b SET came with Shuguang Black Treasures; I upgraded from the BTs to Sophia Electric Royal Princess and then from the RPs to Takatsuki 300b tubes. The built-in cabinetry (including custom CD storage by the Kennebec Company in Bath, Maine) is on the wall apposite the speakers; speaker wires are concealed and run through the walls and under the floor from one side to the other - a distance of 30+ feet. The cherry cabinets have soapstone countertops that were mined in Vermont. Since my house is a converted bank that has appeared in many architecture and design magazines, the physical appearance of the components could not be ignored. Zu speakers and Ancient Audio electronics fit into the modern industrial design aesthetic perfectly. One word about the size of the room. . . The living room (primary listening area) is one end of an open volume that is 20'x40'x16'. I wanted speakers that could fill this space as needed as well as be optimized for the primary listening area.