ORD 734 Diffuser Started by axzan on 10 April 2009. 1 reply. Originally posted at johnlsayers.com, topic 11902. axzan10 April 2009#1 Hi, any spec to DIY a ORD 734 Diffuser?Image not preserved: qrd.jpg Ethan Winer10 April 2009#2 Look here: Acoustic Calculator