Operators' Union. It was released on July 26, 2005 as an arcade game using Namco's System 246 arcade system board. The game uses the touchscreen Rewritable Stage arcade cabinet, which issues the player two rewritable cards containing the player's profile and save data. It also makes use of Sega's ALL.Net network service to keep track of national idol rankings. The network was discontinued on September 1, 2010, though a few of the arcade cabinets still survive. The game was ported to the Xbox 360 on January 25, 2007, and it was released on Microsoft's Platinum Collection on November 1, 2007. The Idolmaster became available for download through the Xbox Live Marketplace on August 11, 2009. Namco Bandai Games released 12 downloadable content updates between January 24 and December 25, 2007 available through the Xbox Live Marketplace. The updates include new costumes, accessories, stages, and additional side-stories called "Idol Dramas". Music The Idolmaster features 10 songs in the arcade version and 6 additional songs in the Xbox 360 version written and composed by a variety of songwriters. Ishihara asked Hiroto Sasaki, one of the music composers, to compose normal pop songs that would not sound odd or similar to songs "from bishōjo games." The music staff was otherwise given the freedom to compose what songs they wanted. The composers were first introduced to the characters, and then personally chose which girls they wanted to compose songs for. In the arcade version, the nine songs for the idols were composed first as theme music for each girl, followed by Koyama asking for one more song with a "European" feel to be composed. Since each idol can sing any of the songs in the game, this resulted in 90 separate recordings over a period of two months. The songs from the arcade version were released by Nippon Columbia on a five-part CD series of compilation albums titled The Idolmaster Masterpiece between 2005 and 2006. The songs from the Xbox 360 version were released by Nippon Columbia on a four-part CD series titled The Idolmaster Masterwork between 2006 and 2007. The first release was the single for on December 20, 2006. This was followed by three compilation albums. Songs from The Idolmaster were also released on The Idolmaster Master Box volumes one and two between July 19, 2006 and April 4, 2007. Reception The Xbox 360 port of The Idolmaster sold 25,000 copies in