This Vocaloid paper craft is the Kagamine Rin, created by Skullkid. Kagamine Rin & Len is the second product released on December 27, 2007, they are Vocaloid2 Character Vocal Series developed by Crypton Future Media Ltd. (CFM), male voice (Len) and female voice (Rin). Their family name was from the developing code combining Kagami (mirror) and Ne (sound).
Crypton Future Media intended to project a Vocaloid with low-teen girl's voice at first following Miku Hatsune, but there was a demand for a boy's voice, so Crypton Future Media hired a voice actress who can produce both sounds. Kagamine Rin was the first voicebank developed and introduced to the Vocaloid consumer market on November 8th 2007. However, the package included two voicebanks: one for Rin and another for Len, both provided by the seiyū Asami Shimoda, Kagamine Len was unveiled later after Kagamine Rin on December 3rd 2007. The package was priced at the same price as Hatsune Miku, even though there was two voicebanks in the box.
At the time of recording in 2007, their names had not yet been decided. Their given names of Rin and Len were said to be based on "right" and "left" according to Asami Shimoda. She later confirmed in an interview after the Append release, the name itself was based on the names of Ken and Rin from Hokuto no Ken, the names were derived from a discussion about names that were familiar from her childhood. According to Asami Shimoda, Len's voice was achieved by singing within her chest, while Rin's at the top of her head.
On June 12, 2008, Crypton announced that the updated edition, named "Act2", would be released in early July 2008. Crypton Future Media apologised for the bad quality of the original Kagamine Rin/Len product. They explained that they had rushed the Kagamine product onto the market in suite of Hatsune Miku's success and promised to produce a better quality version to correct their mistake. The product itself had been in production between April and September 2007 and had not been changed between then and their release. The following April they continued to work on the vocals from where they were left off to tweak the issues surrounding them. Crypton Future Media also promised to speak more closely with the fans and keep them up to date more on their Vocaloid software progress in future.
The new version was released to address issues with the original voicebanks that affected their ability to sing clearly. The Database was resuffled around to allow the voicebank libraries to handle the samples better and Crypton Future Media worked heavily to improve the vocals. Act2 was as an independent installation, coexisting with the initial software.During the Kagamine Act2 production, Crypton Future Media also took the time to change the End User agreement on their CV series to make it easier to understand.
Users who had bought the old version got an expansion disc free of charge, this continued until 20th September 2008 after which users could no longer register to recieve the Act2 software for free.On June 18, 2008, beta demonstration songs using the new version were released on the company's official blog; and on July 18th, the act2 was released. The original version of the software is now retired from sale by Crypton Future Media themselves and it is now no longer possible to buy the software from them.
After Miku Append began, Rin and Len were confirmed to have appends being worked on. Len Append was in the process of production first and demos of his voice were given out. The append was officially released on December 27, 2010. The total number of voicebanks for each one is 6. There are 3 voicebanks being assigned to each Kagamine and had been created from vocal performance of their voice providers. Sample demo songs have been given out on Crypton's official page and their official Youtube channel online. Rin's appends are "power", "warm", and "sweet". Len's appends are "power", "cold", and "serious".
Their Append outsold the Miku Append during the period after their release. However, they did not maintain this, in June 2011, their Append had fallen to 8th place, one below Kaito's Vocaloid voicebank.
You can download this Vocaloid paper craft model here: Vocaloid - Kagamine Rin & Len Free Papercraft Download