The D4 has a wider dispersion than the larger models. The high-performance D4 is a true coaxial loudspeaker with a true compression driver arranged concentrically so that the upper frequencies emerge through the center of the low-frequency driver's magnetic structure and the cone through a Tru-Phase? high frequency waveguide. This special construction provides consistent wide dispersion down to 16 kHz, almost completely eliminating high-frequency rolloff. Further pattern enhancement is achieved by precisely mounting the low-frequency driver (and its concentric HF driver) centered on the baffle, in contrast to offset designs used by others.
The D-SERIES offers powerful magnet structures and efficient coils to ensure high performance, resulting in more headroom per power amp. The D4 is available as a complete set, including everything needed for standard installations, and can also be ordered as separate faces and rear covers. The model has a built-in autoformer allowing it to be used in 8 ohm or 70V/100V applications. D-SERIES in-ceiling loudspeakers are ETL listed and all models have been ETL tested to comply with UL1480, UL2043 and CSA60065. .PAR MORE SPECS