yeah spectrum analysers are ok to make sure you don't have any weird spikes etc, but mixes need to be about balance more than flat frequency response. If you put early minus or plastikman stuff through a specturm analyser you get a weird looking freq response, but they are killer tracks with incredible production and mastering.

Have tried plenty of monitors, recently had to trade in my mackies for KRKs but to be honest any decent studio monitor will replicate the audio signal with flat response accuracy - I just have a personal problem with a certain high frequency range that sounds overly nasty.

Been thinking about putting a compensating EQ curve over my master out to correct for my ears/painful taste - take well mastered tracks and put an EQ setting over them to get them to sound "how I like"... the theory being that I I then make things "how I like" once the compensating EQ is taken off it should be "how things need to be".

Cheers for the book tip mate, will have a dig about for it.