‘Chicago III’ arrived 55 years ago this week as their third consecutive double album in less than two years. Yet Chicago was somehow still pushing the musical envelope.

Even 45 years later, ‘Chicago XI’ isn’t their best-loved original-lineup album. Yet, for better or worse, it remains one of the most memorable of the era.

In retrospect, it’s not hard to see why this copycat-sounding self-titled debut is their only LP. ‘Gerard’ is perhaps the best Chicago album of the era.