Terry Howard, Ray Charles’s engineer, offers some tips on mixing professional singers:

Electronic Musician magazine interviewed Howard last year, and he shared his thoughts on working in digital with Ray Charles:

That’s the whole thing: when you get into working a microphone with the proximity effect and knowing when to get close and far and how it changes the sound, you’re not necessarily paying attention to the level. And the other problem, when everything was 16-bit you could not go that low [with the recording level]. Once you got down to a certain level, the resolution started to change and the sonic quality was not as good as analog. At 24-bit, you can record stuff down 20 dB, and have that headroom. People forget that.