Doesn't it seem that old vinyl records sound better than MP3s?

Wow, most of the commentary on here is totally irrelevant and uninformed. The answer is yes; MP3 is lossy compression, so some of the sound is lost when you convert it to MP3. The fewer bits-per-second are used, the more sound must be thrown away to fit within the bit allotment. MP3 needs at least 256Kbps to be anywhere near high quality, but most sites sell downloads at 128Kbps, which results in a significant quality loss that is obvious and painful to a trained ear.

Furthermore, the analog vinyl did not suffer from high-frequency clipping like digital recording does. A CD or standard MP3 can only capture frequencies up to 22KHz. DVD movie audio can capture up to 24KHz, and DVD-audio can capture up to 48KHz. Some will tell you that the human ear cannot perceive sounds above 16KHz, but this is only a half-truth. It is true that the human mind cannot recognize distinct sounds that high, but the higher harmonic overtones in music are still perceived at a subconscious level as part of the whole sound, and that is another way in which vinyl is superior to digital recording.

One other insidious little trick is that while the MP3s are ripped such that they can theoretically capture sounds up to 22KHz, it is not uncommon to intentionally discard all frequencies above 16KHz to leave more bits available for the lower frequencies, using the logic I explained above. Oh the joys of living in a world full of people that can't hear frequencies higher than a 100Hz thump.....