UP-FRONT Tunes is a YouTube channel dedicated to some artists of UP-FRONT like Aya Matsuura, KAN, Takui Nakajima, etc. The channel's style is more jazzy, bossa nova, etc., in one word, relaxing.
You also have the opportunity to discover some PVs but also live' songs, so do not hesitate to check this channel!!
Personnally, I felt in love with the cover of "Watarasebashi" with Aya Matsuura, a song which has been a huge hit in the 90's (this song has been released in January 1993). It was originally a song from Chisato Moritaka, another UP-FRONT's artist. I hope you will like it! Aya said she was a huge fan of her ;)