What you refer to as a 'developing ear', I refer to as training an ear. It basically only comes from experience. Learning what to listen for and how to listen. It's not rocket science, it just takes experience: time, patience and money to try many varied pieces of gear.
I do believe that the ear is continuosly being trained, or developed, just as any other skill (say driving), until you finally reach the point when your skills begin to deteriorate.
I do believe that the ear is continuosly being trained, or developed, just as any other skill (say driving), until you finally reach the point when your skills begin to deteriorate.