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<blockquote data-quote="audioholic" data-source="post: 7240078" data-attributes="member: 549629">I didnt read Cruzer&#039;s link, but knowing the authors, Im sure their information is 100%. But if you want cliff notes...XBL^2 is also known as dual-gap, because there&#039;s an extra groove machined in the motor (hence &#039;dual gap&#039;) to redirect motor flux and widen its concentration area to include more of the coil&#039;s linear stroke.LMS is a special way of winding the coil so that more wire is located on the ends of the coil than in the middle (hourglass shaped). This difference in wire along the length of the coil corresponds to the loss of magnetic flux as the coil moves away from the center position (and highest point of mag flux). Basically the further the coil moves out of the gap, the more wire it has to absorb/utilize the weakening magnetic field. If done properly, the result is equal magnetic force being applied no matter where the coil is and how strong the magnetic field is there.Split coil is similar to LMS, in that it uses multiple coils on the former, As one coil is moving out of the mag flux concentration, the other is moving in. Net result, same amount of force at all times (theoretically).JBL uses an interesting variation of the split coil and split gap (2 coils, 2 gap locations) called differential-drive. The two coils are wired backwards from each other, and placed in opposing magnetic fields. This means their force is coupled together, while the coil surface area is doubled. Better heat dissipation, less power compression, flat BL, and inductance is lowered which flattens the impedance curve. This is the motor design used on the infamously well performing JBL WGTi series of subs.</blockquote>

[QUOTE="audioholic, post: 7240078, member: 549629"] I didnt read Cruzer's link, but knowing the authors, Im sure their information is 100%. But if you want cliff notes... XBL^2 is also known as dual-gap, because there's an extra groove machined in the motor (hence 'dual gap') to redirect motor flux and widen its concentration area to include more of the coil's linear stroke. LMS is a special way of winding the coil so that more wire is located on the ends of the coil than in the middle (hourglass shaped). This difference in wire along the length of the coil corresponds to the loss of magnetic flux as the coil moves away from the center position (and highest point of mag flux). Basically the further the coil moves out of the gap, the more wire it has to absorb/utilize the weakening magnetic field. If done properly, the result is equal magnetic force being applied no matter where the coil is and how strong the magnetic field is there. Split coil is similar to LMS, in that it uses multiple coils on the former, As one coil is moving out of the mag flux concentration, the other is moving in. Net result, same amount of force at all times (theoretically). JBL uses an interesting variation of the split coil and split gap (2 coils, 2 gap locations) called differential-drive. The two coils are wired backwards from each other, and placed in opposing magnetic fields. This means their force is coupled together, while the coil surface area is doubled. Better heat dissipation, less power compression, flat BL, and inductance is lowered which flattens the impedance curve. This is the motor design used on the infamously well performing JBL WGTi series of subs. [/QUOTE]

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