--- - |2 Abstract This study considers the role of different cognitive units in sound change: phonemes, contextual variants and words. We examine /u/‐fronting and /j/‐dropping in data from three generations of Derby English speakers. We analyze dynamic formant data and auditory judgments, using mixed effects regression methods, including generalized additive mixed models (GAMMs). /u/‐fronting is reaching its end‐point, showing complex conditioning by context and a frequency effect that weakens over time. /j/‐dropping is declining, with low‐frequency words showing more innovative variants with /j/ than high‐frequency words. The two processes interact: words with variable /j/‐dropping (new) exhibit more fronting than words that never have /j/ (noodle) even when the /j/ is deleted. These results support models of change that rely on phonetically detailed representations for both word‐ and sound‐level cognitive units. - Topics in Cognitive Science, EarlyView.