Although a good song, played well, should work in any setting, music styles are still an acquired taste. The kind of music that is pleasant to a senior citizen will often differ widely from the music preferred by today's young adults. Intellectuals who frequent a bar, say in a college town, will usually enjoy hearing sophisticated classical or jazz pieces whereas denizens of middle- or lower-class establishments may not know or appreciate such fare and would probably connect more with familiar pop styles. Therefore, pianists should know their audiences' profiles and tailor music selections accordingly.
Appeal to the nostalgic impulses of an audience. Older patrons will enjoy hearing songs from their younger years, spanning today a range from the Depression to disco. Even young adults can be nostalgic, with a weak spots for hits from the late 1980s and 1990s. You can rarely go wrong by mixing current tunes with a heavy dose of nostalgia, informed by a sense of your likely audience.
Standards have been popular from the "Gibson Girl" era. These tunes are lyrical, fun, and memorable--sometimes with slightly bawdy lyrics. The music of Cole Porter, in the Roaring Twenties, for instance, was exceptionally witty and clever. Many of these tunes have become staples of the jazz repertoire, their chord changes lending themselves to extended improvisational treatment. Good pianists should have a number of "Tin Pan Alley" tunes in their repertoire by the likes of Porter, Irving Berlin, Jerome Kern, and George Gershwin to spice up an evening of music and to evoke an era of high-class pop and jazz.
Slow, romantic songs are popular regardless of an audience's age. A romantic song by Rodgers and Hammerstein, Mel Torme, or even Barry Manilow can charm any room. Unless the setting calls for extended ballad treatments, a little romance can go a long way: a pianist should probably drop a slow, romantic number into a set only every fourth or fifth song selection so as not to become too languid and “sweet.”
Really good piano bar performers are a “triple threat.” They can play piano very well, sing very well, and know how to engage in lively patter with the audience at appropriate moments. They are show men and women who bring a complete entertainment package to the game. If you are the owner of an establishment, know that you cannot change the stripes on a tiger. You cannot ask expert piano bar entertainers to adopt a new “schtick” that does not fit their show style. Gauge the professionalism and the show of new applicants carefully. Avoid making song selection demands that risk alienating the professional too soon in the relationship. Hire new performers on short contracts at first and expand their engagements as you become more confident that their song selections meet your needs.