How close can drivers be to each other in isobarik box

[busterno1]

I am building a isobaric sub with one driver inside the other .

Wired as a push pull . I have 1 inch between the magnet of one & the dust cap of the other is this too close . Will one magnet effect the other being so close .
The xmax of the driver is 9mm . thanks

[mwmkravchenko]

I have done the same many times and it worked out well. The key to a good isobaric is the seal between the two drivers. It must be as close to perfect as is possible. You should always space them the maximum mechanical travel of the driver plus a safety factor of 25% (arbitrarally chosen). The mechanical travel and the x-max are not the same by the way. the mechanical travel is the farthest a driver can be pushed out of it's point of rest as this is the real world worse case maximum.

Mark