The jazz instrumentalist who does more with less has long been popular with aficionados, though the same has not been true of jazz singers, who often seem obliged to wear the music's virtuosity on their sleeve.
It is as if by performing jazz on an instrument they were born with is a form of tax-avoidance, and pretending to be a saxophone instead is the only way to pay off the dues. Only Billie Holiday seemed immune to the complaint that, in touching the original materials of a song with the lightest of breaths, she wasn't really singing jazz at all.
Marion Montgomery, who died on July 22nd aged 67, was just such a minimalist vocalist. Had she been born a decade earlier, she might have benefited more from the ripples spread by young female artists - such as Diana Krall or Stacey Kent - with improvisational sensibilities, but also a cabaret singer's awareness of the curve and drama of a lyric's storyline, and the mood of an audience.
But if Marion Montgomery settled into something of a routine of jazzy nightclub work and posh-cabaret, light-classical crossovers, in the company of Richard Rodney Bennett and others, she could still show glimpses of a jazz awareness that prevented every night from unfolding as the same practised act. She was also possessed of a sumptuously elegant, lingeringly low-lit voice, a subtle understanding of jazz time, and an alertness to the musicians around her.
These qualities had made her a rising star when she first emerged in the United States in the 1950s; when she became more interested in a broader repertoire, and moved to the Britain in 1965, a career path similar to Cleo Laine's seemed likely.
In the event, her musical world was smaller than Laine's, and her work was perhaps trapped a little more by cabaret's invitation to flatter an audience. But her artistry and attention to the minutiae of musical delivery and stagecraft always made her a class act.
Marion Montgomery was born Maud Runnells on November 17th, 1934, in Natchez, Mississippi, and her voice - once compared to "having a long cool glass of mint julep on a Savannah balcony" - rarely lost its aura of louche, ironic southlands ennui. While still at school in the late 1940s, she appeared on television in Atlanta, Georgia, and, from the 1950s into the 1960s, though she also worked in advertising and publishing, she steadily built her career, performing in all kinds of venues, from theatres to jazz clubs to strip joints.
She also studied music and drama, deepening the artistic possibilities of a life spent in clubland. In the early 1960s, she recorded a demo that was sent to Peggy Lee, who listened to it in the company of an A&R man from Capitol Records. "Forget the song and sign the singer," Lee said.
Marion Montgomery got a record contract for the début disc Swings For Winners And Losers, and, by 1965, had graduated to some of the best outlets on the circuit, including the Sands Hotel, Las Vegas, and Basin Street East, in New York. In the same year, the Cool Elephant was launched in London, and she played a season there with Johnny Dankworth's band.
She married British pianist Laurie Holloway, who had worked with a variety of jazz and dance bands, and written a successful musical, Instant Marriage. Relaunching her career in England, Marion Montgomery soon proved herself equally at home in jazz clubs - Ronnie Scott's was a regular venue - and concert halls, as well as on TV
Her stagecraft and laid-back timing - she had an expert instrumentalist's ability to sense how far she could lag behind the beat without the connection irretrievably snapping - allowed her to coax and cajole an audience in small rooms or cavernous halls alike. Sometimes, she would devote an evening to the work of a favourite composer, such as Johnny Mercer, when she could be at her most directly, and revealingly, expressive.
Marion Montgomery and Holloway collaborated on the TV show A Dream Of Alice in 1979, and the singer developed a one-woman show - televised by the BBC - and worked in musicals and cabaret. From the early 1980s, she worked with Bennett, an association that further reduced the jazz spontaneity of her work but emphasised its cool urbanity and upmarket sophistication.
Marion Montgomery and Bennett made a number of recordings together, including the early 1980s releases Surprise Surprise, Town And Country, and Puttin' On The Ritz. The 1987 live session from Ronnie Scott's club, I Gotta Right To Sing, catches Marion Montgomery at her most intimately eloquent.
She is is survived by her husband, and daughter Abigail.
Marion Montgomery (Maud Runnells): born 1934; died, July 2002