Trevor Wilson wrote:



**There's no such thing as a "full range driver", despite the clowns who
imagine a single driver can actually cover 20Hz ~ 20kHz with anything
approaching fidelity. I guess if the limits are +/-20dB.....


** The nearest thing ever made has to be the middle section of a Quad ESL63 or any of its more recent offspring.

A single plastic diaphragm, driven as a series of concentric rings via a delay line produces near perfect sound to beyond 20kHz - to a listener on axis of course. Even produces accurate looking square waves at mid frequencies.



..... Phil