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Message: <blockquote data-quote="newusername" data-source="post: 3941664" data-attributes="member: 562064">Yes, and it should be clear that this is because the flux that jumps the gap (from the top plate to the pole piece) doesn't just exist in the gap...there is a surrounding area above and below the gap called the "fringe field" where a considerable amount of flux can be found (this varies with motor geometry).  The use of a larger top plate can result in higher flux density in the fringe field, which means BL linearity at the outer ends of the coil's movement is improved.The improved BL linearity only really applies, however, if the gap is already fairly saturated.  If it isn't, the taller top plate will result in an increase in flux in both the fringe field and in the gap...the net result is a minimal improvement in BL linearity outside the gap but a large improvement in BL and efficiency.And a taller top plate comes with a few downsides...most notably cost (steel is expensive and becomes moreso everyday) and the potential for flux modulation.  But like everything, it is a balancing act where you choose what your target is and build to that....the final result is a strong function of the assembled parts and a weak function of the sum of the individual parts.The challenge here is differentiating audibility...for example, if I excite a driver with a sine wave of a fundamental frequency of, say, 40 Hz, I can clearly tell when one driver has more distortion than another.  It is plainly audible to my ear at medium to high amplitudes.  But although Fourier described the nature of complex tones as a series of sine waves, hearing distortion in music can be exceedingly challenging...especially in the rock genre where distortion is an intended by-product of the original performance...it's that sonic signature a guitarist looks for.But I do believe there are great strides made on this issue...Drs. Earl Geddes, Lidia Lee, and Floyd Toole (to name a few) have done great work in this field.  Even Dr. Klippel (whose system is actually more production focused than distortion focused) has put in time attempting to decode the ears perception of complex tones.I think the Klippel machine is a great way of identifying the source(s) of distortion and provides a great opportunity for extensive R&amp;D, but as our understanding improves, FEA is growing in popularity particularly considering the price of Klippel's Distortion Analyzer, which poses some problems in it's nature as a statistical fit analyzer and it's sub-par inductance measurement.  But I suppose you know that already. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gifHmmm....what controls the cone?  Oh right!  The motor (BL) and the suspension (Cms).  Again, this is why linearity is important and why Xmax is still relevant in a ported enclosure.  The only difference is that you need less Xmax for a given level of output in a ported enclosure.And it is important to understand the typical tradeoff between efficiency and Xmax.  You can give up some Xmax for efficiency and gain output so long as you don't need the Xmax you gave up.Someone correct me please if I'm way off. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif</blockquote>

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