08-20-08: ShadorneAre these drivers special? Yes. Have I measured? No. This was just an extrapolation, starting at the OMD-15's sensitivity rating of 91dB at 1w input and doubling the power for every 3dB increment until the Amber runs out of headroom. Mirage rates the power handling at 250w. Does this mean it can put out a clean 115 dB @ 1KHz at 1 meter? Probably not, but I feel safer with a speaker with a 250w max rating than an 80w one.
110 db spl clean from a 5.5" woofer is rather a lot (assuming you sit 6 feet back) - are these pro type drivers and have you measured this? Very impressive!
However, I will say that subjectively the bass performance on these speakers is outstanding. It's a 2-1/2 way system, so it's not just a single 5.5" driver handling the bass. When this loudspeaker dishes out with deep bass, it has 2 active 5.5" drivers in separate chambers, one reinforced by a passive radiator and the other by a slot-loaded down-firing port.
Furthermore, these drivers used a special patented "ribbed elliptical" surround originally developed for their powered subwoofers, that is said to maintain linearity while enabling more extreme excursions.
Does it work? I can't measure its excursion vs. linearity, but this 5.5" driver-based system offers up the most effortless, taut, clean, and extended bass I've ever heard from 5.5" drivers. The OMD-15 excels at revealing the nature and quality of the bass you're hearing. It's easy to identify if an upright bass in jazz was recorded with a mic or a contact transducer, whether Charlie Haden should have changed his strings that day, distinguishing tympani from bass drum in large scale orchestral crescendos, organ pedal tones, synth tones, round wound vs. flat wounds on an electric bass--you name it, the OMD-15 reveals it.
It's also particularly good at sorting out melodies and chords and interactions in the bass. I've played several recordings featuring outstanding bassists (Jaco Pastorius, Charlie Haden, Neils Orsted-Henning Pedersen, Ray Brown, etc.) and I get a greater sense of the bassist interacting with the rest of the musicians than before. This also holds true for what it does with left hand chords and bass lines on a 9' concert grand piano.
They play down to about 32 Hz, which is plenty for any music I throw at 'em. I couldn't believe how they fleshed out the big bass drum and gong (which has a low fundamental) on a CD of Copland's "Fanfare for the Common Man."
And it's doing all this powered by this 70 wpc Amber Series 70 amp I was afraid wouldn't do the job.