Hi I usually have a few trusted ears over to audition a new design, and the Song Tower was introduced at a gathering of about 20 DIY enthusiasts, so I got lots of feedback there. When I send the schematic for a new design to Jim, he has his crossover construction dude build a couple of boards and from what I can gather, all of the Salk team on hand fire it up and comment. But Jim knows what he wants, and can tell when he's got it, so I doubt that there's any voting going on. There are certain things you test for in crossover optimization, including off-axis response and reverse null. I do make distortion tests, mainly to make sure I'm not stressing the tweeter too much at the bottom end. But there's not a lot you can do about distortion once the bass tuning, cabinet size, and drivers have been set. I will naturally change electronics as I move the speaker from my downstairs listening comparison room, into my crossover design studio (OK, 5th bedroom), and upstairs to my living room. So I will have listened on a Marsh preamp and amp system, an NAD integrated amp, and an Onix integrated amp, and a variety of fairly modest CD players. But it's never changed my opinion of anything. I'm not much into electronics.