1. Treat your room
2. Treat your voice
3. Treat your mic
4. Treat your file
5. Treat your listener
Treat your room
Ground loop hums are caused by wiring or audio equipment. To avoid this, use the same plug strip for all your equipment. Separate power cords from signal cables to minimize humming caused by magnetic fields. If they must cross, cross them at right angles so they have the least amount of contact possible. Try to keep cables shorter than 2 metres, as coiling causes magnetic fields. Drop them loosely on the floor. To quote Bruce, the neat packing of cables is not your friend. Use balanced (XLR) cables.
Mobile podcasting brings a few solutions. Cars provide podcasters with the ideal soundbooth. Being able to move your podcast to a quiet area, such as a park, is also an advantage (in fact, someone said yesterday that he has podcasted from the local cemetery).
Treat your voice
Bruce recommends brushing your teeth, drinking water with lemon, avoiding dairy. Reading and rehearsing your script is important. Humming, sighs and stretches are important for vocal warmup. Standing up makes you sound more animated.
Treat your mic
Treat your file
Try to get the hottest signal that you can without clipping. If possible, put audio on separate tracks, giving you control over volume. Free filters are available through programs like Audacity and The Levelator (particularly good for panel discussions). SpitFish, FloorFish and BlockFish are free plug-ins that can be very useful. Sound FX are available through ljudo.com, Free Sound Project and SoundoftheDay Podcast. Encode at 44.1 kHz to avoid the chipmunk effect.
Treat your listener
Fill out ID3 tags. Use consistent sound levels.
Thanks, Bruce, for these tips. A pdf version is available through his site.