There is something delightfully non-prescriptive about the word “ensemble”, admitting of many combinations of performers and types of music. It was this notion of flexibility that came to the fore in Friday night’s concert in the Queen’s Hall, Edinburgh. In this, the last of the Scottish Ensemble’s series of creative, time-travelling programmes, we journeyed from Hungary in the 1960s to Cöthen in the early 1700s. The first, really bold move was to put the most difficult modern items in at the beginning, rather than smuggling them past the audience, somewhere between the overture and the symphony.

Ligeti coined the term “micropolyphony” to place us firmly in the world of sound-colours, exploring the world which lies in between the black and the white keys on a piano. Ramifications is a piece that calls for extraordinary precision in execution, with one half of the group tuned a quarter-tone lower than the other half. Not only does the tonality vary, but so does the texture of the sound. At times the bows were several centimetres along the fingerboard, only to swoop directly on to the bridge, all within a single stroke. There is much fiendish counting in the piece and the Ensemble relied heavily on mutual support, direction being ceded from first violin to principal cello at times. The effect of these swirling tonalities was one of inchoateness, a primeval musical soup from which form had yet to emerge. It was as if the concert was beginning directly after the Big Bang.

With Webern’s Five Movements, form did begin to take shape. The first obvious manifestation was the clear division into movements. This was reinforced by sudden, lyrical unison passages, while insistent pizzicato from the cellos and bass during the third section appeared to give the work drive and direction. As with the Ligeti, a full palette of sounds, from mutes to col legno, was exploited. Once more, there was obvious attention paid by each member of the Ensemble to the quality of sound produced; the care with which all the elements were fitted together was equally apparent.

It is nothing new to arrange a string quartet for larger forces, and Jonathan Morton's version of Debussy's String Quartet was as convincing a version of this familiar work as one could wish for. Whereas in its original shape there is the intimacy of four friends talking across a table, this version takes on fresh dimensions. Perhaps because the performers were standing to play, rather than sitting, there was an additional expansiveness to the music’s flow. The addition of double bass pizzicato to reinforce the cellos’ staccato worked particularly well. By using single instruments at key moments, but doubling-up on others (a particularly throaty viola sound in the first movement, for example), additional clarity was achieved. The performance never sounded bloated and what the piece may have lost in ethereal qualities, it gained in extra resonance. Much the same could be said for the Adagio from Bruckner's String Quintet. The control of dynamic was especially impressive in this performance, the subito pianos making dramatic contrasts with well-judged but powerful crescendos.

It was not until a century after his death that Mendelssohn’s string symphonies were rediscovered. Sinfonia no. 10 may well have been an exercise in composition, but so many aspects of the composer’s mature style are already apparent. The exuberance of the music was visible in the performers’ faces. They were at a party, and we had all been invited! This was joyous music, and with Bach's Violin Concerto in E major, the mood was sustained. The well-known opening chords were delivered by Jonathan Morton with three crisp down-bows, setting a brisk tempo. Augmented by Mark Hindley’s sympathetic continuo playing, we were now in a world of structure that was in complete contrast to the opening works of the concert. Paradoxically, we had gone backwards in time but evolved in form.

The concert lacked nothing in drive and energy, while conveying a finely judged range of mood and dynamic. It was by turns challenging and reassuring, but above all it was uplifting and the stuff of which live music is made.