Well, a mono recording has all of the sound mixed in a single channel and was intended to be listened to on a sound system with one speaker - such as a turntable with a built-in speaker. Until the late '60s, most rock and pop albums were mixed for mono, since most young people didn't have access to stereo systems.

Stereo recordings use two, or sometimes more, independent audio channels to create the impression of sound heard from various directions. In stereo, vocals and guitars may be mixed in the right speaker while the rest of the instruments are mixed in the left.

At a recent listening session at Electric Lady Studios in New York City, Apple Records played select tracks from the mono vinyl for Radio.com and other members of the press. The LPs were played on a turntable that was part of a McIntosh stereo system, which attendees were told runs about $85,000, "so you'll probably never hear it sound quite this good again."

"Warmth" is a term that is often used in the analog vs. digital debate, and it is an apt description of why it may be better to hear the Beatles in mono rather than stereo.

Listening to these songs in mono, on vinyl and yes, on a stereo that few can afford in a room that few people will visit, there is a warmth that is lacking even in comparison to the recent 2009 mono CD remasters. The distortion at the beginning of "I Feel Fine" sounds more dangerous, while "Money (That's What I Want)" feels more urgent and in-your-face. There is even an added strain in John Lennon's voice that was nowhere near as apparent on CD.

Great arguments have been made in recent years over why vinyl sounds better than CD, but what is the argument for listening to mono instead of stereo? When it comes to The Beatles, it's actually pretty simple.

"When the early Beatles albums were recorded in 1963 through 1967, mono was by far the dominant format in the UK. Beatles producer George Martin recorded these albums with mono in mind from the start," Bruce Spizer, a noted Beatles expert who has written eight books on the band, told Radio.com. "The stereo mixes were an afterthought, with the Beatles rarely present for the stereo mixing sessions. For these reasons, the early mono albums represent the Beatles music as the Beatles and George Martin intended it be heard."

Spizer even said, "[Martin] viewed stereo as a gimmick for Hi-Fi freaks, something that needed to be done to satisfy the bean counters at EMI."