Q: "I've recently begun recording background vocals/horn sections/string players in my project studio. Instantly, I started having problems with the click track. Even though everyone is wearing circumaural headphones, I can hear the click bleeding through on my recorded tracks. What should I do?"
A: You think YOU have problems! Imagine what it's like on a Hollywood film scoring stage: anywhere from 50 to 100 instrumentalists, all with headphone clicks, miked to the gills with some of the most sensitive mics available. Fortunately we can learn from their experiences to minimize the problems associated with click tracks while recording.
Click tracks bleed from phones into mics for three primary reasons: the click volume is too high; the click attack transients are too sharp or percussive, or the click sound itself contains too much high-frequency (or sometimes, low-frequency) energy. Avoid using most of the default "click" sounds on many synthesizers and drum machines. These are usually drawn from drum kit or percussion sounds that emphasize these problems. Hi-hats, snare drums, claves and rim shots are particularly poor choices. So is a kick drum; besides the risk of a bleeding "thud" in the mics, it can interfere with the rhythmic flow already established by the actual drum track.
A click should be as short and dry a sound as possible. For years, soundstages used a special Urei film scoring metronome. Its high and low frequencies are steeply rolled off but it is still easily heard in the phones. You can achieve a similar sound by taking a side-stick snare or a dull wood block sound and, using EQ, roll off frequencies below about 200Hz and above about 800-1000Hz. Make sure there is no reverb or other effect connected to the sound. Then load it into your sampler or soft synth and let your MIDI sequencer control it (most sequencers have metronome parameters that are easy to set. In addition, letting MIDI control your click gives you the option of changing tempos in a session with minimal hassle).
Recording engineers would frequently have an assistant ride the gain of the click track, turning it down in soft passages and up in loud ones. You can automate this in your sequencer or DAW software, giving you one less thing to worry about.
A final warning about many vocalists (and some instrumentalists): in order to hear themselves better, some of them pull an earpiece off one ear while singing - thus leaving an open transducer within inches of the mic! If possible, pan their headphone mix to the earpiece they leave on. Or, persuade them to rest the earpiece behind their ear but up against their head. An expensive alternative is to invest in a single-earpiece headphone like those used in commercial studios' vocal booths.
