Abstract
In this following study the researcher is occupied with the study of musical performance composition practice and micro timing in traditional Ghanian (West African) percussion ensemble groove processes (using the Asafo “War dance” performance as a case study). The researcher had consecutive percussion lessons for a period of a year, aimed at learning the intimate relations between Asafo groove composition, speech drum practice and highly metrically ambiguous groove micro timing (by John Miller Chernoff (1979) also referred to as “dynamic tension”). For investigating specifically the micro timing between groove instruments, a whole Asafo performance was recorded and all groove instruments had their rhythmic patterns mapped and analysed using a novel computational tool (The Beatspanner). The Beatspanner tool was designed from the new theoretical concept of beat span presented by Chris Stover (Stover 2009), which theorises that rhythms in timeline music (music which is governed by a regular repeating bell or clave pattern) move within a metric force field outstretched between two superimposed 6- and 8-metric pulse cycles. Results from this mapping and timing analysis showed the groove musicians consistently phrased their repeating rhythmic patterns along both the 6- and 8-pulse cycle simultaneously within the same steady groove. Furthermore it was shown that musicians keep their pattern onset timings most stable in relations to each other’s pattern and not so much in relation to the virtual beat span metric grid. Finally an additional finding is mentioned, as it looks like instrumentalists collectively and systematically alternate between accelerating and decelerating their patterns together from one iteration of their groove pattern to the next. This makes the researcher suggest that this is (an unconscious) strategy for negotiating collective tempo, rather than having all musicians mentally aiming at synchronising with one metronomically stable timing ideal.