Re: when recording, what headphones?
Headphones are necessary when you track vocals, drums, and other organic instruments. For electric instruments, if you have the privelege of being able to track in one room, and monitor in another, you can use monitors, since they won't bleed into the mic(s). There are no hard and fast rules here. For monitors I have a pair Thiel loudspeakers that I play with an Audio Research preamp and a pair of VTL monoblocks and a JBL sub. I also have a pair of "cheap" Sonus Faber loudspeakers playing through a receiver for a more 'real world' sound. My 3rd pair of monitors are a pair of powered Roland speakers. For headphones, I like to use Grado, SR125 or SR325. These are open-ear headphones, so you have to watch out for bleeding into the mic(s), but the sound from the headphones is usually way below the source (drums or vocals) and is rarely a problem. I've used headphones and monitors for tracking as well as mixing, and I've had good results using both. If you know the limitations of what you're using, you can mix well on anything, but the key is to play back your mix on as many different systems as possible: table radio, car stereo, hi end stereo, walkman, etc. Hope you find this helpful ...