Is Black Rock Shooter the only anime soundtrack that features vocaloid singers? Black Rock Shooter's opening theme is sung by Miku Hatsune.

Are there any other anime soundtracks that incorporate a vocaloid singer (or a similar synthesized voice program) such as Miku?
It's probably going to be pretty rare for anime soundtracks to be featured with a Vocaloid singer, since the talent tie-ins and money for making anime want to promote their in-house talent so they want to use their own (live) singers. You can see a lot of famous vocaloid producers get hired for their music but instead of the vocaloid voice track, they use in-house talent for the voice:


ryo(supercell) gets hired by Sony Music to make Bakemonogatari's ED, "Kimi no Shiranai Monogatari", but sung by Yanagi Nagi
kz(livetunes) gets hired by Sony Music to produce the song "Irony" for Oreimo, but sung by ClariS
Toku-P had one of his existing Vocaloid songs "Color" used for the Freezing OP, but sung by MARiA
40mP also had one of his Vocaloid songs "Evidence" used for one of the Fairy Tail OPs, but sung by DaisyxDaisy


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