By Jeffrey Felshman

They run the tune again, everyone trying to play fewer notes, and Bloom is a study in concentration. His hair swirls around his bald spot, he cocks his head at various angles, as if trying to tune in a frequency. “OK,” he says when they’re done. “How’d that work for you?” The bass player nods. “Where there’s a lack of constraint, there can be chaos. That’s one of the age-old complaints civilians have of jazz.” Bloom often refers to listeners as civilians.

“You had a lot of good ideas in your solo,” Bloom tells the trumpeter, Aaron Smith. “But you stopped before you developed them, like you didn’t trust what you had.” Smith nods.

The Bloom School of Jazz has been around for a quarter century, and David Bloom is there seven days a week, up to 16 hours a day. He doesn’t get out much, and when he does, it’s usually to a school-related event. He has no wife or children–he’s married to the school. Inside it, he’s a font of sensitivity and compassion who opens his students’ ears and searches their hearts, teaching them truth, beauty, and the Bloom way. Outside it, he’s just another guy who gets no respect.

Bassist Lorin Cohen calls Bloom “the most interesting person I’ve ever met. He reminds me of a Hasidic mystic master, a maggid. He has uncanny insight into the psyche of his students. He can pick up on general moods–he has psychic ability in that way. One time I walked into class, he looked at me and said, ‘You got laid last night.’ ‘Yeah, I did!’ ‘I could tell.’…Bloom has helped me through some dark periods of doubt–I call him, or he can sense it. He understands being a Jewish musician from a milieu of doctors and lawyers, who goes into a field where you make $300 a week.”

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Bloom believes there are certain undeniable, universal truths in art: “In my experience, in many types of music, I’ve seen and experienced certain aspects of the music that are measurable–things that positively are tools of expression. If you look at nature, it’s not just thrown together, and I think that taking a look at art, there’s a craft in all these different disciplines. A lot of schools are just pandering to the lack of discipline of their students–if you come out of art school and you can’t draw, I think there’s a serious problem.” His standards are high, but as Bloom sees it, “Even if you go halfway there, it’s ten times what you normally would have done.”

David, the younger of his two sons, attended the University of Chicago Lab School, but he didn’t like it. “I was kind of like the shoemaker’s son,” he recalls. “I was very rebellious and I had different problems in school.” His parents were gentle, but they weren’t pushovers. “My mom can be a harsh critic, harsh as a heart attack. I like that, I like a harsh critic.” His father “was one of the best ever at asking questions. He could ask you a question that would completely destroy your whole epistemology. If you were being intellectually lazy, he would cut you to the quick. And he would do it in the gentlest way, which is even harder to take. You can’t say, ‘Well, screw you!’ because it’s so gentle and soft and nice.”