I recently bought the PS500 used. They retail for $600 so I figured they must have an awesome sound. Unfortunately, I find them very dull compared to my SR80e which I've owned for two years. The PS500 lack highs and sound like $40 headphones IMO.. Anyone else own these and can comment on what I may be missing? Or has Grado improved the sound so much in last seven years that the SR80e is superior?