Here is something very different than other tunes posted thus far:
Pete Namlook and Lorenzo Montana - Labyrinth Path I. This is an epic ambient tune clocking in a 20 minutes and was only the first track in a double disc set, and that disc set was only one in a series of five double discs. In other words, it is part of a much greater whole. Unlike most other tunes here this one is very chilled out. Atmosphere is heavily emphasized and percussion plays a smaller role, it has an almost cinematic sound. This is not a tune to get your juices going, this is a tune is very mellow. Very deep bass, and very rich use of low frequency sounds, with bass fundamentals going down to the single digit frequencies, although mostly it hovers around 30 Hz. It is not loud though, because the harmonics of those fundamentals are relatively muted. This tune has polyphonic notation in subwoofer frequencies, which is not common. Anyway, if you need to relax, then dim the lights, grab a glass of your preferred beverage, sit down, and give this recording a try.