Nick

I basically started out with a recording I made on my computer and altered it with and old version of Goldwave.

I simply went to "effects" then "filter" then low/highpass. I then set the Initial Cutoff (Hz) to 3000 and then I set "steepness" to 10.

Keep in mind this version of Goldwave is a couple years old. You can download this program for free off the web, at least the last time I checked.

Cheers

jim