From my 'Recording the Beatles' book... Hey Jude was mixed on 5 Dec 69 in room 4 in abbey road studios. Other equipment used was the RS56 UTC Curve Bender EQ used by Ken Scott to salvage some the mix that was recorded in the recording room in Trident Studios on 31 Jul-7 Aug 68. The AKG D19c was used on early acoustic guitar takes of the song, and on many other recordings. Mixed using Tannoy speakers in Lockwood cabinets. Lots of stories in the book associated with the studio speakers and the recording/mixing using the first Trident 8 track mixer in London at the time, including how they were fighting with EMI to use their first 8 track recorder, but used Trident because it became available for their use first. Took quite some time just to look up the details for this one song... tried to summarize the info, but the mixing and recording details are so convoluted I may not have relayed it properly.