Re: bought those kenwood 5.25" dual cone door speakers.....
The size of the magnet has nothing to do with power handling, and neither does excursion. It's all about heat management. A small voice coil has less surface area to dissipate the heat, plus on higher power handling speakers you'll have venting to allow air to flow through the gap and out. Some designs are quite exotic in the way heat is managed, such as the Diamond Audio TDX technology on the Hex Pro 6.5" woofers.
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