Hi Flodstroem
- Yes, you're right. I'm aware that "flux density" is only part of the electromotive equation. I haven't seen comparitive figures ( for a 2225 vs a le15 ) of "total magnetic Flux" . ( Maybe I haven't looked hard enough ). I usually consider the overall "BL" figure as a good generalized term that has accounted for the "total Magnetic flux". But I realize that it (BL ) is also not the full story. Two speakers with identical BL figures but vastly different gap topologies will usually have different "sonic characters" .Earl K, the specs 1.2 Tesla and 0.9 Tesla you mention is from (I guess) the JBLīs T/S parameter list. This spec is given to the "flux density"(eg. Tesla or Gauss), not the "total magnetic flux" (eg. Maxwells or Weber) which was what I meant but couldnīt explain so clear.
I do find the top plate thickness a significant contributing factor to "resolution" / everything else being equal . The ME150h woofer is a good example of that.Its means it is not for sure that the total magnetic flux in a 2225 is higher than in a LE15/2215 (H). The magnetic assembly differs (only?) in the top plate thickness. (if compare 2225H with a 2215H) what I can see. Thats also why the higher "flux density" in the 2225īs magnetic gap.
I agree, in the last 15 years, JBL has increased the thickness of their top-plates for their newer generation speakers ( while maintaining similar BL figures ) . There has also been a small rise in Fs and an increase in midband output . I happen to really like these developments - others may view them as a waste of extra magnet weight & polished steel . These speakers do come with extra resolution - whether the market responds positively to JBLs' gamble / still remains to be seen.I think the total magnetic flux is the main factor which controls the Fs in a speaker. Maybe Giskard is the person who knows anything about the magnets in these speakers ?