Q: “What’s the best way to record vocalists who have different ranges? Should I use a different mic for each?”
Let’s define some terms. No two people have exactly the same pitch ranges but the music world has defined four basic categories, two for women and two for men. Very generally speaking, here are their approximate pitch and frequency ranges (these are rounded off for convenience):
Soprano: Middle C (about 261Hz) to E above High C (about 659Hz), and beyond
Alto: G below Middle C (about 196Hz), up to D above High C (about 587Hz)
Tenor: Second B below Middle C (about 144Hz) to G above Middle C (about 392Hz), and beyond
Bass: E (about 82Hz) an octave and a half below Middle C to Middle C (about 261Hz)
A quick answer would be to try every mic you have and use the one that sounds best for each situation. In general, though, if you have one quality large-diaphragm condenser mic and a good preamp, you should be set. Remember that vital elements of a singer’s individual character are the harmonics that accompany the fundamental notes. Your ability to capture these in a pleasing way is the key to your vocal recording success.
Mic placement will help you control most problems that are associated with individual ranges. Start with the mic on a boom with the capsule about nose height, pointing slightly down towards the singer’s mouth. Try a distance of 6 to 12 inches from the mouth, and be sure to use a pop filter. The following suggestions apply to recording without any compression, EQ – straight from the mic into your preamp:
A Bass obviously needs little low-frequency reinforcement. If you’re using a cardioid mic, avoid proximity effect problems: back him off a step from the mic. An omnidirectional mic or setting has few proximity effect issues, and if your recording room allows it (no reflections or unwanted ambient sound) you could use an omni on the bass. If he’s really loud (and can’t sufficiently control his own dynamics) you could turn the mic a bit off-axis to reduce potential clipping.
Tenors, especially in rock music, can get really shrill and screamy in the upper part of their range. Positioning the mic a bit off-axis might help but it could reduce high harmonics. More distance might be necessary.
Altos are an interesting bunch; they can be deep and breathy in low registers (proximity effect will actually help here) and wailing on higher notes. You might need to “train” your alto to move into and away from a cardioid mic as appropriate for the effect.
Sopranos can sound thin and breathless in the high register (think Joni Mitchell) or they can be clear, bright and overpowering (think Aretha Franklin). You might prefer a medium or small-diaphragm mic if you have one, but your large-diaphragm should still work. Sopranos have important harmonics in the 2kHz to 3kHz range so you have to pay careful attention to how your mic, signal chain, and recording process treats these frequencies. Many mics have a bit of what we call a “presence peak” in this area, which can further complicate matters.
We’ve just brushed this topic lightly; vocal miking and recording is an art and a science that requires tons of training and experience. But if you start with a basic understanding of your singer’s range and characteristics you’ll save time and aggravation in the studio.