When resourcepacks were released, they didn’t change a lot. While they let creators change music and sound effects within Minecraft, this wasn’t hugely taken advantage of. This has changed, with the release of Taiizor’s Tunes, a series custom music packs that replace Minecraft’s default music with something more modern. Specifically, it replaces the record music, rather than the ambient music which sometimes plays.
The original mix was released a while ago, and contained deephouse music, rather than dubstep. Mix Two was released yesterday, and sounds awesome. You can download both mixes from PlanetMinecraft