Maybe this is quite a niche band but last year after I heard them cover 2 vocaloid songs I absolutely love, they just instantly appealed to me, even more so than their stunning rendition of Senbonzakura (千本桜). Senbonzakura is a track that really caught me when playing Hatsune Miku (初音ミク): Project Diva F on the PlayStation Vita (eventually bought KuroUsa-P's (黒うさP) "5th ANNIVERSARY BEST" album because of it), and when I heard Wagakki Band (和楽器バンド) play it I was dumbfounded on how they made it sound even better! What made Wagakki Band's version sound better was that they mixed in traditional instruments, while KuroUsa-P's version used the piano and other modern instruments.
Their first album is more of a cover album of various songs including "Tengaku" (天樂) by YuuYu-P (ゆうゆ), "Episode.0" by Gackt, and other anime cover songs from other artists. The title "Vocalo Zanmai" pretty much says what the album is about. Now I kind of lost touch with them shortly afterwards at the end of 2014 and didn't hear anything much from them in a while until my friend in Japan said "you know that band you liked last year? They have a new album just released and it sounds amazing". So literally through the post today I got a lovely present from her of the album "Yasouemaki" which I can't stop listening to! I thought their first album was good, this is just unbelievable and the album has only recently been released too - well September anyway.
The mix of traditional instruments (Shamisen, Koto, Shakuhachi, Wadaiko, and of course Yuuko Suzuhana's shigin vocals) just works wonders with modern instruments. Of course tradition is in their namesake so you'll always expect their music to have traditional music but wow, if you all haven't heard any of their music then you really must do. Yasouemaki (八奏絵巻) is the album to go for as almost all songs are their own. If you're unsure what they sound like then here's their most recent released track which really shows their talent and the mix of instruments:
和楽器バンド「暁ノ糸」(Akatsuki no Ito) https://www.youtube.com/watch?v=fcucbhJ-Orc