Nu jazz grew out of the combined influences of Jon Hassel's Kiranic trumpet playing and ‘fourth world’ rhythms, Miles Davis' soft tone and use of ambience on In a Silent Way, and the early 90s intersection of jazz and electronica, particularly trip-hop, dub and downtempo. Some early nu jazz artists include Nils Petter Molvaer and Bugge Wesseltoft. Over time, other influences were introduced to the nu jazz sound.
For a time, the jangling ambient guitar sound of post-rock was a big influence on nu jazz, but that has mostly faded now. Meanwhile, bands like Jagga Jazzist and Snarky Puppy have re-discovered the lush orchestrations of sophisticated easy listening and exotica arrangers such as Henry Mancini and Les Baxter. Yet another influence, one that has emerged from the sound of the popular Portico Quartet and others, is the use of repeating minimalist phrases. This use of short repeating melodic phrases not only comes from minimalist composers such as Steve Reich and Phillip Glass, but also from Zeuhl artists and a long history of European art rock. An influence from ambient music is also part of the nu jazz genre, this can be found in the early music of Nils Petter Molvaer, as well as others. Nick Bartsch is a popular nu jazz artist who often combines the repeating figures of minimalism with a dub reggae style ambiance.
All of the above mentioned influences may appear on a nu jazz album, but not necessarily all. As nu jazz continues to develop, the most constant factors tend be a relaxed ‘cool’ approach, an influence from modern electronica and an appreciation for ironic kitsch and retro sounds. Some early precedents for nu jazz can found in the Terry Riley influenced ambient sections on Soft Machine's Third album, Brian Eno's use of Brand X's funk / fusion backing tracks in building his late 70s ambient art rock albums, and Miles Davis' lengthy He Loved Him Madly from his Get Up With It album.
Although there are musical differences between nu jazz and contemporary jazz, from a pop-culture standpoint, the more obvious difference between the two is nu jazz's self-aware ‘hipster’ stance, compared to contemporary jazz's more emotionally earnest approach.