[opnly bafld]

Yes, the new F15 as compared to the previous (older) F15.

There are 2 different models now, new Fast-15 (on sale $549/pair) and older still available F-15 (on sale $399/pair).

https://www.lii-audio.com/product/one-pair-15-inch-full-range-speakers-optimized-detail-frequency-response-and-soundstage-fast-15/

https://www.lii-audio.com/product/recommended-15-full-range-speaker-driver-for-music-loudspeaker-with-tube-amplifier-f-15-in-pair/