> I guess it's like the old WCFL when they used to
> > speedup the singles to cram in more songs per hour.
>
> Actually, the purpose wasn't to cram in more music. Back in
> the heydey of Top-40, stations would speed up their
> turntables, in order to make their competitors sound
> sluggish. This trick is still used today with CD players, by
> stations of various formats.
> >
>
I remember a Buffalo Top 40 who would not only speed up the tracks, but also fade out of them painfully early to get their 20 songs per hour in.
I even recall an Alternative station in the early 90's (that, other than the music, sounded a lot like a Top 40) that did it as well (it was a strange listen...Green Day on helium). Think it was in the Carolinas.
I'm sure this was easier to get away with back when most young folks had low end turntables or cassette decks which always seemed to run a bit fast. Once I had decent equipment, I could hardly tolerate the way-off-pitch playback.
As far as album vs. single edits, there are many cases I actually prefer the single. Wall Of Voodoo's "Mexican Radio", for example (much punchier than the album version).