The best karaoke experience New York has to offer is at this sophisticated piano bar. One low-key recent Sunday night, an intimate crowd sat around the baby-grand Baldwin that anchors the bar. Someone performed, of all songs, “Flagpole Sitta,” checking the lyrics on an iPad and receiving a backup vocal assist from that night’s hyperskilled pianist, Drew Rakowsky. (Up next was “Memory” from Cats.) A gentleman who had just come down from the stage rhapsodized, “Sid Gold’s is a magical place,” then resumed imploring everyone around him to sing. Magical it is, and sing you should: Sid Gold’s can transform even the most self-doubting karaoke virgin into a performer, quelling any anxiety you may have about singing in front of an audience, let alone with a live pianist.