I thought it might be useful as a reference point to specify at least some of the program material auditioned in evaluating the "performance" of the Alpha 4A panels in the bedroom system as discerned from the nearfield listening position used separately by my wife and me. All of it was laptop-fed and consisted of everything from CD rips (16/44) to high-resolution PCM (24/88 through 24/352) and DSD 64 and128 downloads.
Pictured below is a representative, though by no means complete, sample of the auditioned material:
Adding the Alpha 4As' "scatter" to the room improved transparency noticeably, whether the source was the twin guitars of Carlos Barbosa-Lima and Sharon Isbin, the voices of Mirella Freni, Christa Ludwig, June Monheit, or Sarah Vaughan, the more-distinctly-layered choirs of the Turtle Creek Chorale, the cymbal brushstrokes of Johan Dielemans, or massed tuttis wrung out of the Boston Symphony or New York Philharmonic by, respectively, Andris Nelsons and Leonard Bernstein.
I'm ordinarily not into "gimmick" recordings, but I had to try something out, given the broader rear-of-the-room diffusion envelope afforded with all of the Alpha 4As in place. Back in the early 1970s, San Francisco Bay Area FM station KIOI (or "K101" as it was marketed by its owner, James Gabbert) combined on occasional weekend evenings with classical station KDFC (Wikipedia says KFMS, but that's wrong) to broadcast quadraphonic programs, with KIOI on the front channels, KDFC on the rear.
Having built a Heathkit Scheiber decoder, a second tuner (Dyna FM-3), and a second amp (Dyna SCA-35) as well as owning a spare set of speakers (AR-4x's), I hosted several neighborhood listening sessions in my then-Pacifica home to the combined broadcasts. One of the pieces broadcast at every session was the Mystic Moods Orchestra playing Maurice Jarre's title theme for "Grand Prix"--and it was backgrounded by Brad Miller-mic'd race cars (Formula 1s?) tearing around the track. The illusion of being surrounded by all that horsepower in quad was quite impressive.
I've gotten "close" with the two-channel version over the years (I think thanks to an out-of-phase mix on the stereo recording), but I wasn't prepared for how far behind my listening position the cars "go" with the Alpha 4As installed. I'm not suggesting that as a selling point, but simply to indicate how effectively they "open up" the room when positioned far enough behind the listener. (And, yes...the "saint" also appreciates hearing Brabham, Clark, Hill [both of 'em], Ginther, and the rest roar around what I now call Woodhenge.)