you can never go wrong with any AN drivers with a proper enclosure. for my ears classic drivers has better bass response than super cast frame models. My classic 10" can rival the SQ of my super 12 CF.....pero pag pinag sabay sila!!!!!!!nirvana effect na
Whizzer Cone
So what we have in his Audio Nirvana, Super 8, Minimonitor is a highly efficient (98dB/watt in this enclosure, he claims), full range, eight inch paper driver, with a whizzer cone set in a dual- concentric mode on the same voice coil, with a metal phase plug in the center. Actually, what is called a phase plug is a mechanical device that manages to align most of the high frequency waves so as to correct for arrival time anomalies produced by the whizzer cone. The phase plug really doesn't effect phase so much as eliminate time smearing. To correct for out-of-phase a mechanical device would have to find the outer cone going in and out in reverse (or nearly) of the whizzer cone. That can't actually be the case as both cones are affixed to the same voice coil, the difference in their mass and diameter making a mechanical crossover. But a center plug can correct for treble frequencies coming in part directly from the whizzer cone's front, mixing with back waves that then reflect off the larger cone behind it. Lots of manufacturers use phase-plugs, even on less complex (no whizzer cone) models, to adjust the arrival times of frequencies generated by the inner and outer regions of a driver. See the Parts Express website
www.parts-express.com, or Madisound's
www.madisound.com.
Phase Plug
No one has yet come up with a quick, two syllable phrase for anti-time-smearing-plug, so it is known in the trade as a phase plug. (Perhaps "nose cone" would suit the purpose better.) In this case it is lathe-turned from a solid ingot of aluminum (to avoid the ringing that comes from hollow plugs), that is copper-plated for performance and cosmetic purposes (Aluminum, un-plated, gives off a moldy-looking white powder oxide that looks crummy and can find its way into the voice coil gap.). This plated and lacquered nose-cone is bolted and glued to the center of the speaker's chassis. Theoretically, the plug deflects the high frequencies from the frontal waves of the whizzer cone so they take a path less like a flashlight beam, and in so doing arrive at the listener at about the same time as the back waves of the whizzer cone reflecting off the larger cone. I'm not up on the math of exactly how this works, but if having a wide and deep sound stage is any measure of the success of this speaker's ability to eliminate time-smearing, then I'd say it is a pretty successful design in that regard.
