My 2 sets of BB's arrived the other day and I've let them settle in a bit. I'll be posting my full impressions later today over on Teajay's Aether Audio Black Box review...but suffice it to say..WTF!! WOW! Wonderful. It's as if the amp/speaker connection just got fused together, and the overall efficiency of the speakers just got a whole lot better. But more than that. The transient response is clearly improved. Harmonics, microdetail, ambient cues, air around instruments, and stealing from Teajay's vernacular..image density (the ability for images floating in space to take on more body, more palpability) all improved significantly...this is not subtle folks. I will say that the boxes, cold from UPS delivery, did seem to make my speakers (bass) feel almost overpowering at first....but that upper bass bloom settled out within 24 hours and is completely gone. Realize, there are slight ribbon dielectrics to be charged, and some capacitor break-in at work here.
Bob Smith, although now a close friend after all these years of working with him, never ceases to amaze me with his knowledge, his product value, and his simplified tackling of an issue up till know unbeknownst to most of us...in this case..the highly ineffective signal path and feedback loop of an amp and its speakers. And I use Remote Sense cables, which monitor that feedback loop. Still, my changes were noticeable on first note!
For the record..my amps: Spectron Musician III Mark 2 monoblocks, my speakers are Bob's SP Tech Revelation MRI Mark 3's with external Mundorf crossovers. The BB's go between the crossovers and the speakers.