Pittsburgh's Chatham Baroque is a niche within a niche, but its attendance is growing

What most people refer to as “classical” music covers about a 1,000 years of music history.

That’s a lot of ground. Within that span are Russian nesting dolls of niches and sub-niches, including the capital-C “Classical” period that ran from around 1750-1820.

One of Pittsburgh’s musical groups, Chatham Baroque, which is both a musical trio and an organization, specializes in roughly the 800 years’ worth of music before that period, particularly in the Renaissance and Baroque periods.

That’s a lot of ground to cover.

Chatham’s main trio includes a violin and viola da gamba — a kind of historic cello — with historically authentic sheep-gut strings (ew) and a theorbo — a plucked string instrument, like a guitar, but with a double-necked design allows it to reach a vast range of pitches.