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<blockquote data-quote="audioinformer" data-source="post: 6697426" data-attributes="member: 577879">If you take the RD Alpha and the Sundown Nightshade v.1 as is with the coil over hang as X-max at 100% of the Bl value taken with 1 watt 1 meter T/S parameters, then two Alpha&#039;s have more displacement. If you continue on the 70% Bl as true X-max (as it really can&#039;t be because this value can change as conditions change while playing the subwoofer and moving the coil out of the gap) then the Alpha&#039;s still should have an advantage. The Nightshade has a 25mm top plate, and your claim is that the voice coil can move 8mm out of the gap and maintain 70% Bl and the Alpha has a 21mm top plate which, everything being equal, it should be able to move minimum 4mm past the gap and still maintain 70% Bl or better. So, the Nightshade has an X-max of 23mm and the Alpha&#039;s have an X-max of 20mm.Coil OverhangTwo Alpha&#039;s 980cm x 1.6cm = 1568cm^3Nightshade 810cm x 1.5cm = 1215cm^3OR70% of Bl for X-max for the Nightshade (8mm) and half for the Alpha (4mm)Two Alpha&#039;s 980cm x 2.0cm = 1960cm^3&nbsp; (4mm past the gap)Nightshade 810cm x 2.3cm = 1863cm^3 (8mm past the gap)ORHalf of the Top Plate plus coil overhangTwo Alpha&#039;s 980cm x 2.65cm = 2597cm^3Nightshade 810cm x 2.75cm = 2227.5cm^3These two driver are to close for the Nightshade to over come the cone area with cone movement. But, if I were asked which I would chose, I would go with which every company would help me more in the future. I will not state my opinion here but, I just can&#039;t see where your math adds up is all......</blockquote>

[QUOTE="audioinformer, post: 6697426, member: 577879"] If you take the RD Alpha and the Sundown Nightshade v.1 as is with the coil over hang as X-max at 100% of the Bl value taken with 1 watt 1 meter T/S parameters, then two Alpha's have more displacement. If you continue on the 70% Bl as true X-max (as it really can't be because this value can change as conditions change while playing the subwoofer and moving the coil out of the gap) then the Alpha's still should have an advantage. The Nightshade has a 25mm top plate, and your claim is that the voice coil can move 8mm out of the gap and maintain 70% Bl and the Alpha has a 21mm top plate which, everything being equal, it should be able to move minimum 4mm past the gap and still maintain 70% Bl or better. So, the Nightshade has an X-max of 23mm and the Alpha's have an X-max of 20mm. Coil Overhang Two Alpha's 980cm x 1.6cm = 1568cm^3 Nightshade 810cm x 1.5cm = 1215cm^3 OR 70% of Bl for X-max for the Nightshade (8mm) and half for the Alpha (4mm) Two Alpha's 980cm x 2.0cm = 1960cm^3 (4mm past the gap) Nightshade 810cm x 2.3cm = 1863cm^3 (8mm past the gap) OR Half of the Top Plate plus coil overhang Two Alpha's 980cm x 2.65cm = 2597cm^3 Nightshade 810cm x 2.75cm = 2227.5cm^3 These two driver are to close for the Nightshade to over come the cone area with cone movement. But, if I were asked which I would chose, I would go with which every company would help me more in the future. I will not state my opinion here but, I just can't see where your math adds up is all...... [/QUOTE]

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