[1] Kaplan was born at French Hospital in New York City on March 3, 1941,[2] and grew up in Lawrence on Long Island.

He rented Avery Fisher Hall in New York for his public conducting debut in 1982, leading the American Symphony and the Westminster Symphonic Choir.

[7] Tim Page wrote in The New York Times: "Only now will musicians, scholars and the general public be able to own a facsimile manuscript of one of the composer's symphonies.

[13] Steve Smith wrote in The New York Times of this concert:[14] That Mr. Kaplan is no professional conductor was immediately apparent.

Only in a few passages, like the pages of heavenly bliss just before the first movement's tempo-sostenuto conclusion, did a curl of the lip suggest that he was swept up in his work.

From the acute punch of the opening notes, every detail of this huge, complex score came through with unusual clarity and impeccable balance.

It seems likely that no one is better equipped to reveal the impact of precisely what Mahler put on the page.David Finlayson, a trombonist of the New York Philharmonic who performed at this concert, offered a different perspective:[15] Having not previously heard either of Mr. Kaplan's two recordings of the symphony, nor having seen him conduct, I came to our rehearsals with an open mind.

His direction lacks few indications of dynamic control or balance and there is absolutely no attempt to give phrases any requisite shape.

One would think that after more than fifty performances of the work, even the most plebeian of conductors would have some understanding of how to bring together musicians that are separated by great distance.

This assertion is an insult to all professional musicians who have dedicated their entire lives and have sacrificed much toward the preservation of all the great works of history's finest composers.

His continued appearances are also an affront to all "real" conductors who have toiled relentlessly for the recognition they duly deserve.In Kaplan's conducting engagements of Mahler's Symphony No 2, he did not accept a fee.

[23] Kaplan was the younger brother of Joseph Brooks, an Academy Award-winning composer who was found dead at his New York City apartment on May 22, 2011, in an apparent suicide while under criminal indictment on multiple sexual-assault and rape counts.

Mark Swed criticized the choice, contrasting the "reptilian wannabe conductor" of the film with the real Kaplan, who he called a "kind man who died seven years ago and who cared deeply about music and people.