Double Stack or Tripple Stack ?

[Lord Baccus 1]

what is the differance in a Double Stack or Tripple Stack sub ???

how does it affect the preformalce ?

[JimJ 11]

On a very intuitive level, more magnets are going to provide a stronger magnetic field.

Whether or not that's a good thing depends on the motor design. You could have five stacked magnets but if you reach other limits of the design with only two, the extra are just adding weight.

[dopey 0]

I don't think adding magnets = more magnetic strength. Adding magnets = LONGER magnetic field. Strength is determined primarily by Gauss.

More magnets = longer gap = more AVAILABLE xmag = more AVAILABLE throw = more AVAILABLE xmax = greater possibility for SPL.

But xmag/xmax is just one little component in the quest for SPL.

Edited June 6, 2007 by dopey

[DevilDriver 28]

I don't think adding magnets = more magnetic strength. Adding magnets = LONGER magnetic field. Strength is determined primarily by Gauss.

More magnets = longer gap = more AVAILABLE xmag = more AVAILABLE throw = more AVAILABLE xmax = greater possibility for SPL.

But xmag/xmax is just one little component in the quest for SPL.

Adding more to the stack only works if the steel is not already saturated. At that point, you can achieve higher BL through integration of B. Of course, adding more B is totally useless if you haven't got the L to integrate the flux.

More magnets does not translate to a larger gap, a taller top plate does. But! A taller stack can be used to gain more clearance in the rearward direction; yes, you could just machine a taller top plate, but it proves more challenging to saturate and magnetic material is much less expensive than the purchase of raw steel and the machining required after the fact.

All things considered, a thin and wide magnetic structure is preferable, but this really limits your rearward clearance.

[Lord Baccus 1]

i really like this Forum.. ask a question and get real answers...

i had allways wondered why some subs had 2 & others 3 !

what about pole venting ?

i noticed that all of the subs i have owned have a pole vent,

and my friend got 2- 15" Mtx 9500 and there freeking huge with NO pole vent ???

[DevilDriver 28]

i really like this Forum.. ask a question and get real answers...

i had allways wondered why some subs had 2 & others 3 !

what about pole venting ?

i noticed that all of the subs i have owned have a pole vent,

and my friend got 2- 15" Mtx 9500 and there freeking huge with NO pole vent ???

It depends on the application. In a lot of standard high power subs, you'll find a pole vent to help dissipate heat. However, a pole vent can be a bad thing. In terms of cooling, the idea is to move as much air past the coil as possible. A pole vent usually means that the vent is one of the exit points for the air that cools the coil. If we plug this pole vent and change some motor internals (like adding venting to the pole piece), you may find that there are other ways to route the air and cool the coil more efficiently. This is something that is done on the BTL from Fi Car Audio.

[helotaxi 46]

Pole vents can have different effects on a sub's performance. They are not needed in all cases. It all depends on the design goal of the sub. It affects the Q of the sub and also the flux of the motor. More metal in the motor assembly for a higher B might be more important to the design of the sub than the cooling or Q effects that having a pole vent might have. Cooling can be realized in other ways and the Q can be changed other ways as well.

[DevilDriver 28]

Pole vents affect can have different effects on a sub's performance. They are not needed in all cases. It all depends on the design goal of the sub. It affects the Q of the sub and also the flux of the motor. More metal in the motor assembly for a higher B might be more important to the design of the sub than the cooling or Q effects that having a pole vent might have. Cooling can be realized in other ways and the Q can be changed other ways as well.

Exactly. Like virtually everything, it's a negative if it detracts from the intended design and a positive if it adds to the intended design.

[Mark LaFountain 1,054]

i really like this Forum.. ask a question and get real answers...

:dance: :dance: :dance: :dance: