The main synth was a Yamaha CS-80. This is a polyphonic synth, one of Yamaha's first. On Deep Blue Day there are two guitars, a strumming Strat plays the rhythm and the steel guitar is my Sho-Bud single neck Professional. They were both recorded DI. Eno put a massive treatment on everything. The complexities of the chain are unspeakable! But those treatments were worked on for weeks on end.