what to look for in "audiophile" grade parts....

Contemplating an amplification upgrade...what does one look for in regard to audiophile grade parts...for example $500 intergrated vs a $1500 one...I read all this jargon about mosfets,discrete circuitry,fets,o-amps,1% tolerance transisitors,capacitors...what I am getting at is...when upgrading I would like to get not only improved sonics but a lasting design with quality parts...or is all this meaningless and should I be committed now...help me from going mental!