- Name: Yoichi Hayashi (林陽一)
- Birthdate: March 28th, 1967
- Website: http://insomnia.selfip.com/index.html
Yoichi Hayashi was the main sound director for several early CS pop'n music games, from the first pop'n music CS up to pop'n music 9 CS, and was in charge of porting the spin-offs ANIMELO and DISNEY TUNES to PlayStation. He joined KONAMI on October 1996, and was in change of the music programming of games like Tokimeki Memorial ~Oshiete Your Heart~ (ときめきメモリアル〜教えてYourHeart〜) and Jikkyou Powerful Pro Baseball S (実況パワフルプロ野球S).
Yoichi moved to KONAMI's Shanghai branch in April 2004, until August 2007, when he left KONAMI.
- はやP / Haya-P
- Color Essence
- わがまま7 / 長門マチ (with Akiko Hashimoto)
- ミッキー・マサシ (singing alias)
- Shine All Stars (member of)
- もりのおんがくたい (member of)