Not a bad idea about the putty. In the automotive industry we use a material we call 'dum dum'. It's about 1/4" - 3/8" diameter 'rope' that comes in a roll. Black and gooey used to seal HVAC in cars. I think our parts department has some.   ???

I'm thinking I'll make one entire side removeable to ease in driver musical chairs. Will probably design some overbuilt PITA as a gasket. Thought about a 48" piano hinge to make almost a closet door type setup. You've seen the pins racecars have to hold the hoods on, that would be the latch. Would require extensive gasketing, almost like a refrigerator. Somehow keep gasket in place during use.  No, .... I won't call fridgedaire and ask the spl rating of the fridge gasket.  ::)

Bob

Yea, "Camper tape". much easier to work with.
Bob

Of course, Sean is right, but I was thinking we had gone past reality and were engaged in thought play at this point. At least that's what I got from your hinge idea.

If you're worried that it will take a long time to decide which "tuning" you prefer, don't. You have 2 drivers, right? You also have 2 ports and 2 chambers, the center one doesn't make sound so it doesn't count.

Placing them with the magnets in the center chamber will give you the lowest tuning in both ports.

Placing them with the magnets in the vented chambers will give you the highest tuning in both ports

Both of those arrangements will give you a push-pull loading with the drivers firing in opposite directions and result in the least non-linearity distortion. Either way I would wire them electrically out of phase with each other so that they work in unison...... both helping each other.

You can also place the drivers with both magnets down, push-pull. This will give you the lowest tuning on the low port and the highest tuning on the high port. In other words the widest bandwidth box.

Reversing them and placing both magnets up gives you the narrowest bandwidth.

I prefer the lowest overall tuning.

Try Tools / Internet Options / "delete temporary files" (delete all offline content)...... "delete cookies". You might make sure your browser checks for newer versons of stored pages under settings, also. That stuff becomes corrupt sometimes if you use Windows.

The only caution is for other sites you visit that log you in automatically using cookies. You will have to log in to everything again.

I have found that this site dumps you off at odd times or when you least expect it, especially if you refresh a page it many times logs you off as part of the command. Security reasons, I guess.

now about the magnets in center chamber : there would be another advantage besides lower tuning. the cones will couple together better and improve linearity because it's sort of an isobaric loading

"ISOBARIC LOADING" is a term I've heard many times, not very sure of the meaning.

Dowel rod sounds like a very good idea, but the Daytons I have, have a hole in the center covered with a screen. Don't know how I'd attach the rod.

Bob

That funny hole is necessary for cooling the voice coil. Don't block it! You could still have the same bracing by using a flat board with a "U" shape cut out of the ends. Make the U bigger than the hole and it won't impede the airflow.

"Isobaric" refers to pressure or more precisely, equal pressure. When you put 2 drivers together and make them work as one, the pressure between them remains equal on one side of the motor and aided by the other motor and cone, gain a little bit a stability from the "loading". Two motors working as one, coupled with an equal(izing) pressure chamber in between is stronger than one motor.

Many people will say it's a waste of a good driver and that one driver alone will be just as good. They would be correct as far as the first half, or so, of the drivers operating capability goes.

It's when you really need to lean on the drivers that the benefit from iso-loading becomes apparent. When really pushed, the double motors are more stable and resist over-excursion better than one single driver alone can.

In addition to all that, when you have them facing each other and they work as one unit, any non-linear distortion will be averaged and theoretically reduced to one half. Non-linearity is caused from a driver moving in one direction with a different compliance, or restance to movement, than it moves in the other direction. If it moves out easier than it moves in, or vice versa, you have a problem ...... a very common problem.