Some of the material for the "Anthology" was supplied by Yoko Ono, and originally came from a collection of homemade cassette tapes that Lennon had used to capture ideas. Other sources included live performances at New York's Madison Square Gardens, plus studio tapes of "John Lennon/Plastic Ono Band" and "Double Fantasy" albums.
Because these were less than ideal sources, Producer/Engineer Rob Stevens used CEDAR's DCX declicker, CRX decrackler, and the DHX dehisser to remove a wide range of noises from the tapes.
Digital editing was carried out by Paul Goodrich who explains, "Before we purchased our CEDAR Series X units we had to use material that wasn't too noisy. For example, we had two live recordings of Lennon at Madison Square Gardens. One was very good but noisy, the other wasn't so good but contained less background noise, and we had to work with the inferior material. Since we have purchased CEDAR we can remove this noise, taking advantage of better sounding recordings and material that previously would have been unusable."