Dentist Rock

When a man, usually caucasian in his mid-30s to late-50s that works in a profession other than music, gets dumped or divorced after a long relationship and "rediscovers" self-expression in the form of music.
Because their sense of style has frozen since the beginning of said relationship, it's usually heavily indicative of some long-forgotten or now derided genre or artist.
It almost always suffers from very low production value in both audio and the visuals for whatever medium on which they release it.

While the name implies a specific genre, it can also come in the form of hip hop, metal, jazz, or any other style of music.

See: "Moon River Rock" or "Can I Borrow a Feeling" for examples.