Henry Erben was born in New York City in 1800. He built organs under his name from 1827 to 1884, building as many as 1,000 instruments including the organ in Trinity Episcopal on Wall Street. The Erben organ in the Old Chapel at Festival Hill was built in 1835 original for a church in Maine and for many years resided in a Methodist Church in Showhegan, Maine. The one manual, 11 rank organ is a rare survival of the Erben's early work. The classical case is 14 feet tall, 9 feet wide and 6 feet deep and has 14 half stops and 484 pipes of both wood and metal.
The organ is the oldest American built organ in use in Texas today. It is a fine example of English style organ building of the 18th century, which was common in 19th century America. The organ arrived at Festival Hill in May 1993 and was dedicated in May 1997 after a complete restoration.