From
Designer > World
'firsts' timeline > 1991: Introduces Imago. It features an Anechoic Transmission
Line cabinet for the
woofer to trap and control all rear waves it emits, resulting in a minimum-phase
shift, first-order, low-frequency rolloff; an exponentially-flared transmission-line
behind the tweeter’s dome to dissipate rear waves for more natural treble;
an isolated, double-walled cabinet construction to decrease
resonances,
built using M-3's complex techniques; a cast marble faceplate that
descends
from Type 4732, improved with a non-resonant recipe and acoustic foam to
cover it to reduce reflections; and vibration-isolated, outboard, first-order
crossovers that descend from Type 4732 and M-3. Johnson's new Balanced-Phase
circuit design reduces distortion and Crossover-Adjustment Modules allow fine-tuning without switches or knobs. Ability to be biwired or
passively
bi-amped continues from Type 4732. An outgrowth of his college senior
research project, Imago's sound dispersion decreases smoothly from completely
omni-directional in the low bass to perfectly directional at the highest
frequencies -- a technique he names Frequency-Selective Dispersion.
