Vocaloid Wiki
"Miki" redirects here. For SF-A2's voice provider, see Miki Furukawa.

SF-A2 miki VOCALOID2 VOCALOID4 | Songs Albums Notable Originals

SF-A2 codename miki (SF-A2 開発コード miki) is a Japanese VOCALOID distributed by AH-Software Co. Ltd. in collaboration with HEARTFAST, and was initially released in December 2009 for the VOCALOID2 engine. She was updated to the VOCALOID4 engine in June 2015.[1] Her voice is provided by the Japanese female singer-songwriter, Miki Furukawa (フルカワミキ / 古川 美季; Furukawa Miki).



Often shortened to just "SF-A2 miki", her codename of "miki" comes from her provider's name "Miki Furukawa". In Japanese, 'codename' or 'development code' translates as 'kaihatsu koudo'. The meaning of the "SF-A2" part of her name has never been stated.


Her VOCALOID2 design was unique among the VOCALOIDs. She had no references to YAMAHA based musical instruments and was designed to look cybernetic, giving her a more sci-fi look than most other VOCALOIDs at the time.[2] She generally has a star-theme motif and has a star symbol somewhere in every design for her.

According to information that came from the 2012 redesign, miki was designed to look like she was made out of an inorganic material and was conceptualized as an android. Her body was designed to look like that of a child, but also give her the overall appearance of a young teenage female. Though she is an android, she is covered in muscles made from various materials such as carbon nanotubes, but were made loose to give a mild deformed look about them. Having an immature-looking body allowed her to appear younger than she looks, similar to how Hatsune Miku and Kagamine Rin could do the same.[3]

The illustrator also gave an "SFA2 bike" version in 2010 showing miki with her hood up and on a sci-fi themed bike.

Her look was given an overhaul in her VOCALOID4 update and her cybernetic flesh appearance was abandoned. The general science fiction appearance, however, was kept.


For more on VOCALOID relationships, see the FAQ.

  • Utatane Piko - Originally, miki and Piko were developed as a pair, but due to complications, they were split between two companies.[4]



To promote the release of SF-A2 miki, an album featuring her singing Christmas songs, VOCALOIDS★X’MAS, released in November 2009. Notable VOCALOID song creators' works are included.[5][6]

She, along with Kaai Yuki and Hiyama Kiyoteru, were introduced to expand the VOCALOID market and to give producers more choices.[7]

Until May 2011, all AH-Software VOCALOIDs were banned from KARENT.


SF-A2 Miki - Natural
The "Natural" vocal is meant to be a realistic representation of the provider Miki Furukawa. At the time of its initial release in VOCALOID2, it was considered the most realistic Japanese professional voicebank. It was also noted for its ability to sound like a different vocalist in different ranges, leading to high potential for voice morphing thus allowing it to sound very different to its raw unedited state.

Music featuring SF-A2 miki[]

  • On this wiki, SF-A2 miki is featured in 65 songs , 61 albums , 5 series , 1 events.
Niconico logo
Translation ミキミキ★ロマンティックナイト (miki miki★Romantic Night)
SF-A2 miki
Categories Original song
The third song of the Samfree's Night Series.
Niconico logo
Translation Mujin Eki
SF-A2 miki
n-buna (music), 大里正毅 (mixing), Awashima (video)
Categories Original song
YouTube logo
Categories Original song
Niconico logo
Translation サテライト (Satellite)
SF-A2 miki
Peperon-P (music, lyrics), Mikuriya Wata (illust, video)
Categories Original song
Search for music featuring SF-A2 miki [show/hide]



Google Trends



SF-A2 miki was the most popular of the first three AH-Software VOCALOIDs. However, all three were slow to gain popularity and were among the least popular of the Japanese VOCALOIDs for a while.[8] When interviewed, Tomohide Ogata mentioned he had a feeling SF-A2 miki was very popular overseas.[9]


An independent search on Nico Nico Douga revealed that most VOCALOIDs had less than 1,000 videos uploaded in 2011 between July 1 and December 15. SF-A2 miki fell into this category.[10]

  • Kio's model is available for purchase from Windows 100% magazine and the MMD Starter Pack magazine. Previously, the model was available to download from his site, however, it ceased distribution after users violated the model's terms of use.
  • SF-A2 miki's voice provider, Miki Furukawa, used to work for Ki/oon records, which is owned by Sony: the same group Utatane Piko's provider, Piko, comes from.
  • One of the first 3 AH-Software VOCALOID2 voicebanks to be released
  • One of the two first female AH-Software VOCALOIDs
  • First VOCALOID of the Artist Edition series to be released


External links[]

Language Description Site
Japanese AH-Software official homepage Link
Japanese VOCALOID2 SF-A2 miki product page Link
Japanese AHSoftware The official YouTube channel Link
English deviantArt , art and media community Link
Japanese Pixiv , art and media community Link