Just a little twist on the topic...Actually, I'm kind of opposite of Mean Dean...I'm often thinking, "If the singer would just shut up, I could hear more of the interesting subtleties going on in the background instrumentals". There is lots of good stuff in the backing tracks from the 60's and 70's, as there were great musicians in the Wrecking Crew, The Funk Brothers, Muscle Shoals, etc. who backed many of the singles we heard. Sometimes the backing track could darn near stand alone as an instrumental.
One of my favorites is below. Also, many of the great backing tracks that the Funk Brothers did for Motown have also been released, and are a great listen.
Below, at 2:05 there is a noticeable mistake in the bass line. I read an interview with Jerry Scheff, who played bass on "Along comes Mary". There were several takes made, and he was shocked when he heard the take containing his mistake in the released version. He said this mistake actually bothered him for several years, and he dreaded hearing the song. Then one day, he was in an elevator, where the musak version playing in the elevator actually duplicated his "mistake". Hearing that "relieved the burden" he had been carrying about "Along Comes Mary"...