Frank Zappa’s involvement
Frank Zappa plays piano on “Softly, Softly”.
Quote from Michael Chain, founder and lead singer of The Knack posted on Zappateers:
“Frank DID play on piano for me on Softly Softly (the only non-member of the group to play on a KNACK record). Frank was recording next door to me in studio B at Capitol (I think he was working on Lumpy Gravy)… Frank was a great guy and played on Softly as a favor because I didn’t want Capitol Records bringing in an outside studio cat who might influence my sound.”