I've been doing studio sessions sporadically for over a year and am almost ready to send the tracks for mastering. We're in the mixing phase, but I find it very difficult to judge the mix when at the studio. I can think much more clearly when I'm at home, when the time pressure is off.
However, away from the studio I don't have the expensive studio monitors or headphones. I listen to the tracks using the various cheap headphones I have -each with their different characteristics -and try to judge the mix by taking the "average" of how they sound.
E.g. if the guitar sounds too loud on one pair of my headphones, but about right on the other pairs, then I won't ask the engineer to change the guitar volume when I go back the studio. If the drums sound too loud on all pairs, then I'll ask him to bring them down. He gives me the altered versions and then we repeat.
Is this a silly way of working -need I buy an expensive pair of open-back headphones such as Sennheiser's HD 650? But I can't plug them into my laptop I assume? (What I use to listen).