What is your minimum SPL requirement?

[NoDestiny]

Geolemon is my cleanup crew when I throw down things without thinking of giving a full explanation... Thanks buddy, exactly what I was trying to say in a terrible cliffnoted version.

One thing I wonder (in a very dedicated install): If you do ported enclosures in your doors, would the placement of the port effect the response and potentially give you a way to counter the null? I'd assume it would. Be a crazy process to figure out where to put it if so! Could really do some insane tuning that way...

[geolemon]

I was wondering the exact same thing, honestly - even wondering how much loss there would be if you vented into the space behind the door panel, rather than making an explicit [read: ugly] opening for the vent...

The vent really is only contributing near the tuning frequency, then rolling off above that.
At lower frequencies, bass penetrates - and door panels are hardly thick or well sealed at any rate - but there's more than enough space behind them that I'm confident you wouldn't be generating massive amounts of sound pressure that would be trying to knock your door panel off it's clips.

It would really be pretty easy to run a PVC vent sideways across your door panel a few inches to the middle or so...
And honestly, if doing enclosures, there's not really a need to seal off the whole door structure like you usually do. Could just vent it into the door cavity, I imagine - same effect.

Same for a passive radiator, and that might even be more weather-friendly. It seems like it's always raining or snowing here, so sealed (I mean that in the weather-tight sense) enclosures with 8" PR's - why not?

I wonder if you could basically build these with basically the same kind of design your run-of-the-mill Creative and Logitech computer speakers with their little 6" subwoofers use. Could end up with four of those in your interior as midbass...
...and in my case, I want to have a separate DSP preset for when I take the sub entirely out of the car.
Why not shut off the sub channel and let these run like four small subs?

I haven't even had my door panels off yet - I'm hoping I have enough of an opening somewhere that I could mock up a styrofoam buck to 'glass up, and be able to get it into the door cavity.

Damn you, now you have my imagination going.