Metal Cones -- Always Promising -- Finally Can Deliver On Their Promise
Metal cone woofers have held potential for superior sonic resolution, but until now it was necessary to either live with the High-frequency ringing or attempt complicated solutions to suppress the the ringing (mechanically or electrically). The patented Joseph Audio Infinite Slope(TM) Crossover, with its unique 120 dB/octave rolloff, is the natural, simple partner for the metal cone. Now we can hear the full potential of the metal cone, without the problems that have plagued them previously.
Metal Cones have incredible performance advantages over conventional woofers. Yet... In order to realize the huge potential of the metal cone woofer, one major obstacle must be overcome.
Fig. 1 - Cumulative Spectral Decay of Ringing Metal Cone Woofer
As seen in figure one, the woofer's response is dominated by sharp ridges of energy - ringing at 5000 and 7000 hertz. It literally wants to ring like a bell. Conventional crossover networks cannot correct this problem, and speaker designers either let the resonance remain, add complex RLC parallel or series networks in order to tome the resonance, or resort to using softer materials that distribute the resonances across a broader range. Less successful metal cone designs have been described as sounding "harsh" and "nasal".
Fig. 2 - Cumulative Spectral Decay of Metal Cone Woofer with Infinite Slope Crossover
In Figure Two, one can see how effective the Infinite Slope Crossover is at silencing the woofer before it has a chance to ring. No additional circuitry is needed. A silk dome tweeter (not shown in the graph) extends the treble response cleanly post 21,000hz without any ultrasonic ringing. You'll only find this combination of technologies in Joseph Audio speakers.
