Use this table to sort the 313 pibrochs notated by 1841. Have fun playing around with the order in which you sort the columns. You can sort by scale (pitches used or omitted) and structure (the nearest calpa or Ùrlar ‘frame’).

The nine categories of calpa have more to do with utility than reality. They are a street-view rather than a satellite-view map – useful but not accurate. Pibroch composers had great fun playing off the tension between what the brain expects and what actually happens – so don’t expect the calpa to be observed strictly. They are the patterns an expert listener would most easily recognise. When settings depart from them it is not necessarily a sign of corruption. More often than not, it is the whole point: a display of skilful craftsmanship, a sign of cultural confidence.

I like to think of them as reductionist rationalisations that facilitate memorisation, teaching and extemporaneous (re)composition – pibroch’s equivalent to the 24 measures of Welsh cerdd dant (‘string craft’), structures supposedly drawn out of music by a council that met at Glendalough around 1100, convened by the high king of Ireland. They are a theoretical construct, ‘coarse-graining’ or removing noise so that a clearer pattern emerges, one that can be taught and helps everyone to get their bearings when the territory is unfamiliar.

Tonality & Structure