In Montreal, a city that has cavalierly razed one heritage building after another, why should anyone care that the Palais de Commerce is no more - structure neither old, nor beautiful, nor architecturally distinguished? But when I exited Berri-UQAM metro last December to gaze on the gargantuan empty site, I felt a pang. It was the same pang I felt two years ago, when I opened The Gazette to a photo of the unprepossessing building that was once the centre of my life, and learned it was slated for demolition. The article argued for the Palais preservation and incorporation into the Grande Bibliothque projected for the site. But its fate already seemed sealed.

During the years that I frequented the low-lying, block-long structure between Ontario and de Maisonneuve on Rue Berri, I rarely heard it called Palais de Commerce. Inaugurated in 1952 as Montreal's main exhibition hall, it was the Show Mart - or Le Show Mart Building, which says something about language in Quebec in those days. The downstairs show space was continually booked for commercial exhibits, sports events, and cultural activities; I learned from The Gazette that Cardinal Lger hosted community dinners for 6,000 there. But I scanned the article in vain for any mention of what mattered to me: the third floor of the Show Mart was home to the Conservatoire de Musique et d'Art Dramatique du Qubec for most of the decade (beginning 1963) that I studied there.

It was a make-do home for a music school. We had no auditorium, no cafeteria, no lounge. Our orchestra rehearsed a block away, in the dusty basement hall of the Bibliothque St-Sulpice (now Bibliothque Nationale) - or farther afield in a pavilion of the Universite de Montral Id first known, in childhood, as the Jewish Y. Concerts were at Plateau Hall, facing Parc Lafontaine. But everything else - lessons, chamber rehearsals, classes in solfge and dicte musicale, harmony, counterpoint, fugue and composition - happened in the Show Mart, whose upper corridors traced a city-block-long rectangle around the high-ceilinged show space. This was a world of its own.

I spent some dozen hours a week along those studio-lined corridors, whose walls were painted a dizzying alternation of green and blue. Each studio had an outer door padded in dark-red vinyl, an inner door of wood - in each an eye-level window. Walking up and down in search of a practice space (green ... blue ... green ... blue) you could glance into studio after studio: here a violin lesson in progress; there a lone cellist, her wrist oscillating in slow vibrato; here a male singer belting out the chromatic scale on long vowels, up past the fifth and down again, A-o-a-o-a-o-a-o, A-o-a-o-a-o-a-o, Ayyyy! - then starting again a semitone higher. Next door a pianist thunders through scales in double octaves. Then an empty studio - but locked. Another, unlocked - but with waiting instruments balanced on open cases atop the piano. Here is a flutist at his tall music-stand, bobbing and swaying to an energetic etude; there, a solfge class beating time with their right hands; here a percussionist getting up a private racket on cymbals and snares. In every box the feel of solitary or communal industry, of deep engagement.

Our common room was the Vestiaire by the elevator. Lockers lined the walls; a row of windows, too high to look out of, admitted shafts of afternoon sun in which cigarette smoke lingered. Benches surrounded a large oak conference table where you could socialize over a coffee, read a newspaper, eat a hasty brown-bagged or take-out supper, or spread xeroxed pages of sheet music to tape into folios.

The studios were soundproofed, but you could always hear a faint cacophony in the corridor. Even at lessons, the tenors shockingly vigorous a-o-a-o's leaked through from next door. The doors had to be pulled hard, sucking air as the plush edges made a seal; inside, they were lined with strong-smelling cork. Stuffy year round, the rooms were horribly overheated in winter: sweat ran when we played. The windows stuck. What satisfaction to dislodge a frame and let in a frigid blast, mixing with the heat that rose from the radiator-grill to make the air waver and shimmer above the sill.

Ralph Masella's studio was always blue with his Balkan Sobranie pipe-smoke, whose aroma blended nicely with the cork smell. My lessons were at five in the evening. The tower bell of Eglise St Jacques would be bonging its solemn monotone as I assembled my clarinet. Beyond the window, the downtown sky displayed sunset colours above low rooflines, then turned twilight-blue while the city lit up. The window went black and mirrored me back to myself. As I warbled through my endless etude, Mr. Masella would lean back in his chair and sometimes his eyes would drop shut, a slight twitch under the lids the only sign he was listening. I could feel his struggle to stay awake; he worked a long day. With other Conservatoire teachers, in three hours he'd be on stage in the brand-new Place des Arts, playing first chair with the Montreal Symphony Orchestra...