I emailed my friend that owned SpeakerCraft/Marcof Electronics, he has designed a ton of raw drivers for several different people. As an off shoot of this discussion we were discussing how we have chosen an 8 or 15 inch driver for the same design even though an 8 inch and a 15 inch woofer both have the same sensitivity and can be designed as a woofer with the same mid and tweeter, the 15 is still more efficient because how it moved more air more efficiently. Here is his reply:
Tim, while vc resistance is used as a part of motor force calculation, so is the driver cone area. You can build what you want many many ways, but to tie efficiency directly to voice coil resistance is flaky science to say the least.
Design with the highest flux density in the voice coil gap and the highest ampere turns also in the gap with the lightest moving mass with the largest cone size will win the DB/Watt/1 meter race. It doesn't mean a darn thing about how it will sound. :)
Hope this helps some! As you already know, speaker design, is a giant pile of trade offs (at best).
Ed
Tim, while vc resistance is used as a part of motor force calculation, so is the driver cone area. You can build what you want many many ways, but to tie efficiency directly to voice coil resistance is flaky science to say the least.
Design with the highest flux density in the voice coil gap and the highest ampere turns also in the gap with the lightest moving mass with the largest cone size will win the DB/Watt/1 meter race. It doesn't mean a darn thing about how it will sound. :)
Hope this helps some! As you already know, speaker design, is a giant pile of trade offs (at best).
Ed