ORIGINAL: Rev. Jem
Read yep's first post in this thread. HTH
Yeah, to quote Rev. Jim quoting me, the most common reason why people with normally good intonation sing off-key on the record is because of excessive bass or excessive volume in the headphone mix.
We're all familliar with the concept of A440 tuning, but it's not really as simple as strict frequencies.
Believe it or not, pitch perception actually changes depending on volume and frequency. If you take two perfectly "in-tune" notes two octaves apart and turn the volume of one or the other or both way up or down, they will sound out of tune. Same thing with taking two slightly out-of-tune notes and changing the volume. Poor man's autotune. Weird but true. Fletcher of Fletcher and Munson proved this with a bunch of experiments that you can try at home. One of the reasons why concert and orchestral recordings sometimes sound out of tune at low-volume playback.
This phenomenon is especially important at low frequencies, since that's what people tend to "lock on to" as the baseline tonality. Human hearing is also significantly less accurate at lower frequencies, and may hear loud bass notes as fully half-a-step flat or more from their actual frequency.
So by all means, keep your headphone mix at a level that you can hear it, but try to keep it at a typical "listening" level, and turn down the low end a little and focus on the midrange instruments. Resist the common beginner's urge to drown yourself in concert-level headphone volume. Make sure you can hear YOURSELF in the headphone mix as well. A little reverb or delay and some compression or even guitar distortion will help you to hear the performance that's actually going to tape instead of just the resonance in your own nasal cavities.
Cheers.