I've Sound, or simply called I've (アイヴ), is a Japanese techno, trance music production group based in Sapporo, Hokkaidō, Japan. Its songs feature the vocal talents of many different female artists, such as: KOTOKO, Lia, Mami Kawada 川田まみ, AKI (A.K.A. Y. AKI), Ayana, Asuka Katagiri, Fuuran, Inosuke Tsutsumi, Eiko Shimamiya 島宮えい子(A.K.A. PEKO or EIKO), Kaori Utatsuki, MAKO, MARY, MELL, Mihi (sometimes incorrectly referred to as MIKI), MOMO, NANA, R.I.E, SHIHO, TAKAMI, YUCCO, MIKI, Yumi Matsuzawa, Satou Hirmoi 佐藤裕美. Besides vocal artists, I've Sound also gathers many trance electronic artists/groups, such as C.G. MIX, Hard Stuff, Outer, Blue Velvet, NueroSocieta, Fish Tone.
Among Japanese animation (anime) fans, I've Sound is well known for singing the theme songs to many anime, such as Onegai Teacher, Onegai Twins, Shakugan no Shana, Kanon, Air, Higurashi no Naku Koro Ni, Hayate no Gotoku, Maria-sama ga Miteru OAV, Mahou Shoujotai, Kannadzuki no Miko, Black Lagoon. They have also sung the theme songs for countless Japanese eroge video games and visual novels.