JM Labs originated as a speaker manufacturer (JM= Jacques Mahul, the designer of said speakers). Allegedly, Focal acquired the speaker manufacturer who now operates as the finished (consumer) products division of Focal. So it wasn't quite a matter of fitting the drivers into a speaker enclosure -- at least, not in the beginning...
As a general rule, efficiency in drive units is a function of moving parts mass vs. magnet strength. High strength magnets are expensive.
Efficiency in the speaker system, as has been noted, is also a matter of how much energy is used by the filters (x-over, notches, zobels, etc, you name it).
Hence, average magnets with heavy filters, do not a dynamic speaker make! Ultimately, small level info is lost to our perception as Sean notes -- and the result can be pleasant, flat across the critical range, etc, and "laid back".
Re, Sonus Faber & others: don't forget that, while the x-overs may be capacitor-less, it doesn't mean they are simple (1st order, etc) all over (I don't know if they are...). Also, the drivers used, like the expensive Scanspeak woofs on some models, are not that sensitive to begin with... some are ref'd at 86-87db...
As a general rule, efficiency in drive units is a function of moving parts mass vs. magnet strength. High strength magnets are expensive.
Efficiency in the speaker system, as has been noted, is also a matter of how much energy is used by the filters (x-over, notches, zobels, etc, you name it).
Hence, average magnets with heavy filters, do not a dynamic speaker make! Ultimately, small level info is lost to our perception as Sean notes -- and the result can be pleasant, flat across the critical range, etc, and "laid back".
Re, Sonus Faber & others: don't forget that, while the x-overs may be capacitor-less, it doesn't mean they are simple (1st order, etc) all over (I don't know if they are...). Also, the drivers used, like the expensive Scanspeak woofs on some models, are not that sensitive to begin with... some are ref'd at 86-87db...