It really depends a lot on the instrument being tracked. Distorted guitar which is pretty compressed already will not have much dynamic range so -6dB will be fine. But a close mic'd snare will vary a lot in dynamic range when the drummer gets into things and starts hitting it harder, so you might want to keep -10-12dB or so on that. At least that's what I do. I tend to leave a bit more headroom than is probably necessary, but that's just me. You can always add more gain later!

If you are maxing out your summing bus then the solution is to pull the individual sticks back. Tracking with peaks at -6 is so you have a good strong signal on all the individual instruments/vocals. When mixing you have to balance out the entirety which often might mean pulling the faders down on some instruments.

Thanks guys. Yeah, I'm thinking I just need to start the mixing process with every thing down farther and then work it up as necessary. Thanks.

E

Try adjusting your monitor volume so that the sound pressure level is roughly the same throughout the mixing process. If you have an SPL meter it will help you keep an eye on this. If not turn the monitors up a bit when you start mixing and back off to keep a consistent volume as you mix in more tracks.

and what about when the vocals start in the mix, do you do any automation to lower the volume on other instruments?

hate90 wrote: and what about when the vocals start in the mix, do you do any automation to lower the volume on other instruments?

If you put a compressor on the master track of the mix it will do that for you. Also encoding in MP3 will also have the same effect more or less, but it's better to use a master compressor.