TRIOS, quartets and quintets are common enough jazz formations, but a committed piano saxophone duo that has regularly performed and recorded together during four years of hectic and grooving musicianship, each partner also playing in many different bands, is not a common twinship, particularly if this twosome has also produced three outstanding albums during that time.

But such is the achievement of two young men — pianist Andrew McCormack and saxophonist Jason Yarde.

McCormack’s music began at home, where his parents brought him a record which included Miles Davis’s So What.

It was “as if someone turned the lights on,” he declared.

He carried on with his music at Pimlico School and later at the Guildhall School of Music and Drama.

Yarde’s jazz road started on the other side of London, where as a boy guitarist he switched to saxophone at 13, joined the Jazz Warriors at 16 and pursued his music while studying performing arts at Middlesex University.

Their eventual musical partnership began at a session at the Vortex in Dalston in 2008, thus prompting a union which has subsequently delved a mine of beautiful sounds.

The first of these were waxed in January 2009 in Tulse Hill, south London, on the album MY Duo, largely made up of tunes composed by one or other of the pair. Yarde’s startling, birdlike soprano soars into McCormack’s Obsessive in a colloquy of joy while Yarde’s balladic How Long Wil You Hold Me/ is a wordless love song of lucid poignancy, with both musicians forging an amalgam of empathy and deep sensitivity to each other’s testimony.

A foray into the West Side Story score with Bernstein’s Something’s Coming produces a prodigious sonic narrative, each solo building fire.

McCormack’s Tunnel Vision shines with Yarde’s luminous sonic light and the dreamy No Time Can Tell explores the mists with a piercing clarity.

Yarde’s eerily blown Lullaby is a palaver of night creatures and his Breezabeth is sheer thought-in-sound, a running away of the musical minds of two reflective jazz troubadours.

In April 2011 they were back in the studio, this time in Dartington Hall, Devon, to cut the Places and Other Spaces album.

Perhaps Yarde’s Hill Walking on the Tynerside is a key track, dedicated to two great pianists, Andrew Hill and McCoy Tyner, which McCormack grounds with a sauntering rhythmic uplift and Yarde’s alto sings out his tribute with peals of love and hope.

Other spaces has the sound of a much freer fusion and in Holding Pattern Yarde’s soaring yet quasi-subterranean notes flow under McCormack’s darkly serpentine keys.

In The Spaces Before, Yarde’s saxophone begins as a ship’s horn before the duo voyage out on a calm and serene sea of sounds, and the combined flowing energy of D-Town is pulsating and full of life’s blood.

In London sessions of 2012 and 2013 the duo were joined with the cello, viola and two violins of Laura Moody. Vince Sipprell, Emma Smith and Jennymay Logan named the Elyisan Quartet, to make the album Juntos.

They begin in cosy parlance with a Nice Cup of Tea, the Quartet’s strident bows adding the sugar, while in the enigmatic Ob’s First Adventure there is a whole lot of plucking beside McCormack’s powerful striking of the keys and Yarde’s rhapsodic cadences.

The Quartet’s coverlet of stringsong removes the nakedness of the duo’s essential sound but adds new dimensions of fullness and surprise as in From Then On, with Yarde’s leaping curlicues, the sprightliness of Little Door with McCormack’s skipping solo or the growing sense of revelation in the exquisite choruses of London Light.

The west and east of an original London musical achievement in these three records — the true black and white of a compelling jazz cosmopolis.