If the BBC effects discs are or not "faked" doesn't really matter, quite possibly some effects on the disks aren't "real", certainly nearly all are the real thing, even if that can leave you trying to find city tracks that don't have very distinctive London Underground trains rumbling in the background. They're a great resource and I know the problems in recording really good clean effects.

The BBC does use specialists in their radio drama department who can "fake" many sound effects. The sound effects in many films are not the real thing. On this particular film I used a mixture of the discs (some being used in more than one track) and sync water droplets recorded in the studio.

The point I was making is that rain may be one of those effects that can be "faked" rather than recorded naturally.

In sound design, we don't necessarily want things to sound as they actually do. We want them to sound like the audience imagines that they sound.

A great example is recording dialog in a small bathroom. We don't want the dialog to sound like it really does. It has way too much reverb and resonance. We want just enough reverb to make it feel like its in a bathroom, but we want the sound to be better than the real thing.

Fake vs real shouldn't ever be a concern. Good, great, or poor is the measure.

I thought of trying to mix several different tracks together, but I don't think its needed. The stereo track I recorded has passed the listen test with at least 4 people so far, so I think I'll go with it. Thanks, everyone!