How important is tuning?

I had a reciever NAD(25W) and I was playing my music on a Phillips DVD I also had JMlab speakers. I did not like how it sounded it was sharp and edgy. Psychicanimal brought me some cords which he called "tuned", a PS Audio Juice bar, and some sort of cones for the DVD that mad a incredible improvement. The sound was so smooth your ear could not get tired of listening to it. The question is, Is knowing how to "tune the equipment" more important than buying all the expensive things out there??