Sound waves are analog in nature, as they are continuous variations in air pressure. An LP's grooves directly correspond to sound waves, a digital recording does not. It converts the original sounds into a sequence of numbers, and digital recording and playback requires conversions, first from analog to digital, and then digital to analog. The quality of those conversions determine sound quality. Analog recording avoids those conversions, but is subject to a number of distortions that digital audio avoids. Neither format is perfect; we need a new recording and playback technology that sounds more like the real thing.
In the beginning, before Thomas Edison invented recording, music was always "live." It was played for and enjoyed by humans in real time. When the band stopped playing the music was gone forever.
Starting with the earliest Edison recordings in 1877, and right up to the introduction of the CD in 1982, consumer audio was strictly analog-based. We started to hear about professional digital recording in the mid 1970s, but for nearly 100 years, analog was the only audio technology for music, film, TV and radio. Analog was so entrenched it was almost impossible to imagine another technology would ever replace it.
Digital recording didn't take off that quickly, but it slowly became the dominant method for recording and playing back sound. So much so that analog recording without digital conversions in mixing or mastering are exceedingly rare in 2014.
We've always had live music, but whenever you see microphones on stage the sound is being amplified, equalized, processed, and compressed. Live music is dynamically compressed, not as much as recordings are, but it's squashed so you can hear all the instruments and vocalists in balance to each other. Almost all concert music in clubs, churches, halls, and arenas is amplified and processed. Whenever you see computers on stage or the mixing desk, the sound is digital.
So unless you're a musician, or hang out with musicians, you'll rarely hear unprocessed live music; the only common exception is a classical music concert, which are far less likely to be played over speakers.
But I'm wondering, is there another way to capture and replay sound? What will it take to close the gap and make recorded music sound like it was captured without mics, amps, compressors, and other processors? Share your thoughts in the comments section.