All The Beatles' music has been remastered, meaning the engineers at Abbey Road Studio pulled out all the final master tapes (those final mixes of The Beatles' music) and tried to make them sound as pristine as possible, while preserving the integrity of the original mixes. It also means that The Beatles' music now sounds better than ever.
The Beatles' mono box set.
There will be two box sets — a stereo set and a limited-edition mono set that contains everything from 1963's Please Please Me through The White Album (The Beatles), the last Beatles record mixed in mono. It'll also include a CD full of mono mixes of the band's singles.
So why mono? Why, in this day and age, would anyone want to hear The Beatles in one-channel sound?
According to Beatles historian Kevin Howlett, George Martin and The Beatles put the most care into the mono mixes. He also notes a number of differences between the stereo and mono mixes. For example, the mono version of "She's Leaving Home" has a major change in pitch. John Lennon's voice on the mono version of "Lucy in the Sky With Diamonds" has a lot of flange effect on it.
Howlett helped write the new liner notes for the remastered albums. He notes that the recording process "has developed so much over the years. Now you can go back to those (original recordings) and clean them up and remix the whole thing. What they've done, the whole amazing team at Abbey Road Studios, is gone to meticulous care and attention to clean up any blemishes that might have been on the original master tapes that you can now correct. Dropouts on the tape. Or any kind of microphone pops when people were singing too close to the mic. Just smoothing out any kind of blemishes and making it as pristine as possible, but not altering the integrity of the original mixes."