I got to wondering about what to do with the cavity. At first, I thought of stiffening the door card and adding some damping to the metal. However, some of the nicest domestic loudspeakers that I've met have been transmission lines. PMC have shown that such a design can be just as successful in a small, stand-mount speaker (DB1+) as in a large floorstander.
I seem to recall that the cross-sectional area of a line needs to be equal to the radiating area of the cone, so with a 4" driver that is practically nothing. The question, then, is will there be space in the cavity to fold a long enough (1-1.5m) line. I've never taken the door card off, so don't know what complications await in terms of door and window mechanisms.
Has anyone tried this before? Maybe the line could be built onto the door card and run around any obstructions?
It's just an idea and may be a none-starter. Of course, putting a transmission line behind a 4" driver isn't going to magically provide 130dB at 35Hz. It may, though, help produce a better sound than the stock mounts.
Maybe I should stop being lazy and have a look for myself...
Now then, what about taking out the back seat and casting a concrete exponential horn???
- broken
). Having said that, the provision of LF is nothing more than 'adequate'.
