This thesis explores a vowel shift by speakers in Alberta in which [æ] is shifting before [g]. A production experiment was designed to examine the direction, extent, and sources of this change. I hypothesized that differing prompt modalities might elicit productions that could be used to support the existence of a triadic grammar, where productions are influenced by the community (auditory), the self (pictorial), and the standard (orthographic) grammars. I hypothesize a refinement of Ohala’s Active Listener hypothesis to include “super” and “inactive” listeners as other possible sources of sound change. The results show this is an in-progress merger by approximation and that changing the prompt modality altered listener productions. Auditory prompts had the greatest influence on production: Those most likely to merge the vowels [æ] and [ɛ] were more likely to mimic auditory cues. This indicates that super perceivers spread sound change to a greater degree.