Stuff you need to know:
• Analog sound waves are continuous, meaning there are no interruptions or breaks. Digital signals aren't continuous -- they create short bursts of sound of the correct pitch and volume and collect them together to simulate a sound wave.
• Audiophiles value a concept called fidelity, which refers to how true a recorded sound is to the original source of that sound. A high-fidelity recording should sound almost as if you were present during the original performance of the audio.
• If an audiophile tells you that a particular recording has a warm sound, it means that the medium has captured the lower frequencies faithfully.
• Ultimately, the quality of an audio recording is somewhat subjective and dependent upon the listener. Two people may hear the same recording in the same set of circumstances and yet draw different conclusions about the quality of the sound.