"Stereoirregular" is a term that refers to something abnormal, uncommon, or deviating from the standard stereo system. Synonyms for this word include "unorthodox", which suggests being different from usual or traditional stereo specifications. Another synonym is "atypical", signifying something that departs from the normal or expected stereo setup. "Nonconforming" is another similar term, emphasizing a deviation or non-compliance with stereo norms. Additionally, "unconventional" denotes a departure from commonly accepted stereo practices or norms. These synonyms capture the essence of "stereoirregular", highlighting the idea of something that does not adhere to the typical or expected stereo configuration.