I use the Snowball mic by Blue to record my podcasts. When I was researching what was popular out there among podcasters, this mic came up time and time again. While I’ve been impressed by its sound quality (it certainly beats the iPhone earbud/mic combo that I used for “The Twonky”), I had an issue with it right out of the box.
Its three settings allow one to record directly into it (cardioid), record live music (cardioid -10db), and record groups (omni-directional). The latter two settings work fine, but on the first directional setting, there was a noticeable high-pitch hum that accompanied my words.
My first attempt at a solution was to purchase an externally-powered USB hub for the mic to draw power from, but this didn’t help. So I tore it apart to check to see if any wires were in contact with one another. While I didn’t notice anything amiss, I tested out recording while I was squeezing various parts of its innards together. At one point, while my thumb was holding one of the circuit boards in place, I even picked up some AM radio signals!
I eventually gave up and re-assembled it, this time making sure that no wires were within touching distance of each other. I tried recording again, and this time the hum was very much diminished (but not entirely gone).
When mixing and editing all the sound files in Audacity, I use a couple of noise reduction passes to eliminate the remaining hum, but it’s still kind of annoying having to deal with it. When some more time passes, I may invest in the Yeti mic (also by Blue), which seems to be a more professional-quality mic.