It's hard to choose a more different piece in mood from James Brown than this one: Erik Satie's Gymnopedie #1 published first in 1888. Here is a bit of what wikipedia says about Satie:
"Satie and boredom.
Satie often consciously disregarded the conception of development found in the German tradition (Beethoven, Schubert, Schumann, Brahms). Satie's compositions tend to be very short; a typical movement of a Satie composition takes less than two minutes to play, and compositions with more than five movements are exceptional. Even his larger-scale works conforming to the genres known in his time would be two to five times shorter than the usual duration of such compositions (Socrate, a secular oratorio — or "symphonic drama" — lasting about half an hour, is the longest). In general, Satie thought it to be a great fault for a composer to bore his audience in any way."
The following piece is indeed quite short, just over 3 minutes. However, it is also very slow, so you will have to decide for yourself if it's boring. I find it amazing.
This link is to someone on YouTube playing it on the piano. I'd recommend just closing your eyes and listening, but feel free to watch him play as you please.
I actually discovered this music when I was learning classical guitar. However, it's not exactly an unknown piece of music. It's apparently even been covered by Dave Navarro and Blood, Sweat, and Tears among others. Regardless, here's a link to the song on guitar which someone used to show photos of his model railroads.
Finally, if you like this sort of music, here is a less than a minute clip of a pianist playing another one of Satie's works