mr tennis
i propose mid fi is indeed a derogatory termm but meant to imply a pedstrian and mass marketed nature with inferior fidelity relative to so called hi fi
mid fi may or may not be poor quality at least in the context of mass marketed merchandise
i would suggest that Denon and Yamaha in the late 70s and early 80s for example were of high quality but nonetheless mid fi
conversely i propose that garage built and potentially unstable components may be hi fi but not high quality