Jan Welles is not a well-known name in the world of music, making it challenging to provide a factual description of this artist. If you're referring to a specific musician or band called Jan Welles, please provide more information. With the correct details, a precise and informative description covering their musical style, significance, and history can be produced. Without such data, it's not possible to cover any distinctive elements like notable band members, signature sounds, or influential works.