Isn't this just a variation from isobaric loading developed by Harry Olson back in the 1950s?
Yes, I believe so. Magnet-to-magnet is one possible configuration. I built my subwoofers that way.
KEF Blades have featured force cancelling woofers for around 10 years.
MartinLogan has (essentially) been doing that for years! First, with their "BalancedForce" subs, and now, with their latest Masterpiece line. With my ML BF210 subs, as well as my Expression 13A's, I can balance a nickel on the cabinet, then play Béla Fleck's Flight of the Cosmic Hippo. No vibration or resonance whatsoever, even with the deepest bass notes!
Yes, that's why I said ML is "essentially" doing that. They are not physically coupled, but the net effect is the same.
Not to beat a dead horse but they're not essentially the same. One attempts to cancel the rear wave of 2 drivers, the other cancels the stresses placed on the cabinet and the drivers' chassis.
No sir. The physics is exactly the same. The opposing driver forces cancel. There is no "rear wave cancellation". The drivers are IN phase.
This is an ancient concept. I still have a late 90s Pinnacle Baby Boomer stashed somewhere...and they weren't first.
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