If you need to record clean ADR or voiceover, etc, and don’t have access to an audio booth, try recording inside a car (that’s not running, duh)… I guess they’re actually designed to have great acoustics. The only problem is that the actor can’t stand up, which often makes a big difference in delivery, especially if it’s an untrained actor… so maybe just always use really really short actors, I dunno. I can’t remember where I got this tip from… either a book, website or an audio person.
As I’m writing this, I remember a related experience from before I had heard of that. There’s a scene in Nuclear Prom 3000 with two actors exchanging dialogue in the back seat of a parked car, which I shot from the front seat with a Sony VX1000.
As we were setting up mics, I was astonished to realize that the audio from the camera’s built-in stereo mic actually sounded better… which is the first and only time that has ever happened. But I guess it makes sense– that sedan had nice acoustics and we were in the middle of a quiet wooded area. Also, they were moving around a lot and keeping a directional mic properly aimed at them within such an enclosed space would’ve been difficult.
You can also get one of these relatively inexpensive thingees… I have one and it works great, especially for the price.