  Contemporary Ghanaian popular singing combines European and traditional
Ghanaian influences. We hypothesize that access to technology embedded with
equal temperament catalyzed a progressive alignment of Ghanaian singing with
equal-tempered scales over time. To test this, we study the Ghanaian singer
Daddy Lumba, whose work spans from the earliest Ghanaian electronic style in
the late 1980s to the present. Studying a singular musician as a case study
allows us to refine our analysis without over-interpreting the findings. We
curated a collection of his songs, distributed between 1989 and 2016, to
extract F0 values from isolated vocals. We used Gaussian mixture modeling (GMM)
to approximate each song's scale and found that the pitch variance has been
decreasing over time. We also determined whether the GMM components follow the
arithmetic relationships observed in equal-tempered scales, and observed that
Daddy Lumba's singing better aligns with equal temperament in recent years.
Together, results reveal the impact of exposure to equal-tempered scales,
resulting in lessened microtonal content in Daddy Lumba's singing. Our study
highlights a potential vulnerability of Ghanaian musical scales and implies a
need for research that maps and archives singing styles.
