Very good post! This particular point, I just want to caution to watch out if there is an air bag in there which many vehicles now have. Don't want that to blow a tweeter into your eye!
Uh, you might be willing to do "low effort"...but you're talking about miniDSP etc? 😆 If you're gonna do that then do try to damp the door.
- Door cavities are complex, likely not a simple volume but various resonators stuck together, hence TS parameters not too valid except as a general guide. Low resonance and low Q
- Inquiring minds still want to know what year and trim level this Subaru Outback is
- And are the 6x9s in the doors? (That's unusual, but it does happen)
- Components sets will be way better, by virtue of having the tweeter aimable, and a vastly better crossover at least for upper models. You could almost buy according to how complex the crossover looks.
- Results will be comparable to effort, eh?
- Never seen a spinorama for a 6x9, not that I've been looking exhaustively. Please send whatever you decide on to Amir at https://www.audiosciencereview.com to start a trend! And even good upper frequency dispersion won't be good if aimed at your leg 😉
As for the JBL GTO 939 my buddy worked on that, though maybe a previous generation. Funny marketing silliness at https://ca.jbl.com/GTO939_.html (heat sink fins molded around the magnet, but they tout it is carbon, which conducts heat LESS well; somehow the non-magnetic carbon is supposed to direct more magnetic energy...ah takes me back to my days as a marketing *****, such fun). I don't see any crossover box, so it must be a cheapie capacitor behind the tweeters. Hopefully they work well enough for ya!