As I noted in an earlier post, playing back a tape or digital audio recording can help you make out poor-quality recordings, and get past ambient noise that may creep into the recording.
Another help is to use an earplug, like those musicians wear on stage to protect their hearing. I use a brand called "Hearos." These soft silicone rubber plugs allow you hear but reduce volume and seem to filter out a lot of the high-end noise (which is what sounds like a fan or air conditioner or music or airplanes or passing cars make).
I put the plug in my ear and use a headset. Between this and slowing down the recording (and getting words from context or memory) I can work out almost anything that's said.
In a worst-case scenario, you might be able to use a program that allows you to see visualizations of sound (like EasyAudio Editor) to do comparisons and pick out the odd garbled word.
If you are still using a tape recorder, consider switching to a digital recorder like Sony's ICD-P320 (less than fifty bucks, and it can record over 30 hours). Feed the output from that directly into your computer and you can hop from place to place in the recording, while speeding up or slowing down the playback as necessary.
What about voice-recognition software, you ask? That's a question for a later post...
Copyright © 2007, Michael A. Banks