According to Edith Reiter's 2014 book this instrument was completed on 1 July 1972 and originally sold to a buyer in the USA.
Howe & Hurd (2004) describe heckelphone #4973 as a model 36 voll cons.
As of 2019, heckelphone #4973 is located in Pittsburgh (PA), USA, owned by the bassonist James Rodgers, who aquired it shortly before from bassoonist Benjamin Kamins of Pittsburgh (PA), USA. Kamins likely purchased the instrument directly from Heckel.
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