In no particular order ...
Pitch correction: Whether AutoTune or the powerful pitch corrector in my preferred Digital Performer DAW, I'd rather highlight and drag a few (OK, a bunch) of notes around and then iron out the wrinkles, than say, “Alright, you ready for take number twelve?”
The Sennheiser MD 421: Not sure what mic to reach for? In a hurry, no time for experimentation? Put a 421 on it. If it's a horn, a vocal, a guitar, or a drum, it’s good. Matter of fact, if it vibrates air, then you really can't go wrong.
Empirical Labs’ Fatso: The good old Fatso is so good at adding just a touch of gritty attitude to boring tracks and mixes. It’s subtle, but sopowerful.
Universal Audio Precision Limiter: I don't want to compete in the volume wars, but I've been drafted. I slap this simple and transparent plug all over the place (tracks, subgroups, whole mixes, mastering) to try and keep up without making my audio sound like a bug hitting the windshield.
Spotify: Sure, its still only MP3s and its charts move like molasses, but it’s the easiest and quickest way I've found to do some audio research without whipping out my debit card.
Digitech DSP256XL: Talk about “ghetto.” This outboard multi-FX processor was considered sub-par in the early ‘90s when I bought it. But it has this one killer reverb: one program so good that it lit up a recent client’s face like a Christmas tree, just as it’s done so many times before.
Multiple monitors: One full-sized mid-field system with a big ol’ sub, one set of mini full-range speakers and a set of old-school Radio Shack Minimus 7s (don't laugh, as I know a bunch of y’all do “consumer checks” on these, too). How did I ever mix without such divergent points of comparison?
Thumb drives: They help me get audio from here to there most every day, it seems, without any hassles or issues. Small, cheap, portable, effective, durable … what's not to like?
Really crappy mics: Of all the ways to screw things up and get a track delightfully dirty, a terrible plastic mic still beats overdriven preamps, tortured compressors and bit-strangled plug-ins. Tape some foam to the end of it, give it to a singer as a handheld and tell them they've got two tracks to go nuts and have fun ... you'll edit later.
Ampex tape machines: I hear the new plug-in emulations are pretty darn good, but when you need vibe or “finishing,” it's like Marvin Gaye once said, “Ain't nothing like the real thing, baby.”
BIO: Rob Tavaglione is the owner of Charlotte’s Catalyst Recording. catalystrecording.com