I find the info coming from our friends at Alpine to be rather curious. While it is certainly commendable that they invest in
having a Klippel to test their drivers, then they publish the new data on the SWS 15 (per his thread). Furthermore, they claim
this new series is "underhung" design, but looking at the Bl curve, it does not at all resemble the traditional 'flat Bl curve' that
inverted-coil, aka "underhung" motors exhibit. The data sheet info shows a sectional with extended-gap design, but as there
is no clear image of how long the coil is relative to the gap, nor any info on the VC or gap height, as they typically provide, who
To compound this, the posted curve of the SWR "Type R" flat, which IS an "underhung" design (long-gap/short coil), as
illustrated by the lower graph on the SWR, has not been touted as being "underhung," though the gap to VC specs/data,
clearly shows it is. Omitting this designation from the SWR (or an alternative name to denote it is not traditional overhung),
but this seems odd, esp as they now mention the SWS design is 'similar' to the SWR design.
So how do these conflicting circumstances co-exist. You would think they would want to tout the benefits of a more expensive
motor topology (as in Type R Flat), to help justify the price (which they apparently do not), or they would not use that term on
a more affordable (under $200) driver, which ironically for 2012 is FAR deeper than the prior gen type S drivers, and this seems
very strange, as it would make more sense that a 'short-coil' motor would be adopted to "reduce" the motor depth. So the deeper
motor on the new SWS would suggest it is NOT an "underhung" motor at all, and as mentioned, the Bl x curve clearly looks like
it is just a typical, long-coil design (perhaps it is just a long-gap with a long VC, aka "even-hung" motor).
If it is an "even-hung" type design, this would explain the power rating, esp if it is a "short-coil" would not likely handle 500 watts
RMS, even if it is a 2.5" multi-layer (which it no doubt is). If that is the reality, either they are either confused or simply very
concerned with the accuracy of their terminology. In any case it is certainly rather misleading.
Good that Alpine puts the data out there, but really bizarre that they seem to not understand what's what, IMHO. If I have missed
something here, please illuminate me.