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According to official sources, this project was announced to currently be in production or is in its conceptual stages.
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SynthV Studio

ROSA (ロサ) is an upcoming Japanese vocal to be developed and distributed by ZAN-SHIN Co., Ltd., and is expected to release as an AI voice database for Synthesizer V Studio.[3][4] She is also expected to have a CeVIO AI speech voicebank[5] in addition to the possibility of singing and speaking in English for both engines.

Currently, ROSA's Japanese CeVIO AI talk voicebank is prioritized and in production. Her Synthesizer V AI production has not yet been funded nor started.

Her voice provider is Shirayuki, a Japanese influencer and voice actress. She was the chosen candidate from ROSA's audition.


ROSA's theme color is pink and she is the younger sister of the VOCALOID CUL.[6] She is a cheerful and mischievous person.[7]

ROSA has little known backstory, however Hiroto-P noted that she and her older sisters lived together in an old little church on a small hill and that one day CUL appeared and told her that she was her older sister.[8]


"ROSA" can mean "rose", but was selected mainly for its relation to the color pink.


ROSA wears a robe similar to a traditional Japanese Kimono, consisting of a black and pink top and a short pleated maroon colored skirt. The sleeves are decorated with soft pink roses and a curly white pattern. Around her waist is a black Obi (traditional Japanese belt worn around the waist.) laced together in the front. A red bow is tied in the back. The skirt of her top is adorned with the same wavy pattern as the sleeves. Her shoes are tall black lace-up boots reaching her knee. The heels are a deep red. She wears a black choker with silver detailing. Her hair is cut at an angle, stylized in a high braid to one side of her head. The color is a cotton candy pink with a crimson intertwined in the braid. She has many hair accessories, such as a red bow, rose hair pins, and a black ribbon. ROSA has reddish-pink eyes, and rosy cheeks.


  • CUL - Older sister
  • According to tweets from Hiroto-P in 2021, there are other older sisters. The characteristics of them are:[9]
    • Wind: Blue
    • Snow: White
    • Moon: Yellow
    • Flowers: Red
  • Black CUL (Wet Crow) - Older sister and CUL's twin


Throughout 2020, Hiroto-P had been composing tweets in regards to CUL and the many parts of her project. He revealed that REV was meant to become a VOCALOID, but his project fell through, and later revealed that CUL had conceptual sisters themed around the following colors: blue, white, yellow, and red. It was also confirmed that she had a twin sister known as "Black CUL" (Wet Crow). In response to a fan, Hiroto-P also expressed interest in updating CUL but did not give further details.[10]

On March 20, 2021, Hiroto-P confirmed that ROSA, CUL's younger 15-year-old sister with a pink theme, was in production for a new AI singing and talk synthesizer developed by ZAN-SHIN Co., Ltd.,[11] seeming to suggest that VOCALO Revolution would no longer be producing any vocals for the VOCALOID software.

It was mentioned that ROSA's voice actress would be chosen via an audition taking place in April 2021.[12] Hiroto-P also discussed the time when Eri Kitamura recorded for CUL and noted that the voice direction for ROSA's actress would be treated the same.[13] He expressed an interest in creating ROSA's singing voice database for Synthesizer V or CeVIO AI and a speech voicebank for AI VOICE or CeVIO AI, but the final decision would not be announced unitl April.[14][15] In addition, due to an unexpected high interest from western fans, Hiroto-P is also considering a possible English singing and speech voicebank for ROSA.[16]

On March 26, ROSA's illustrator was selected and would be announced once her final artwork was ready.[17] On March 27, ROSA's singing voice database was confirmed to be developed for Synthesizer V. This was chosen due to the synthesizer's ease of use and ability to use VSQx files. In addition, it seems that an AI voice was in consideration along with a standard voice database.[18]

On April 2, a recruitment post for users interested in creating songs and talk segments with ROSA was launched.[19] On April 3, Hiroto-P mentioned that the company was interested in collaborating with Internet Co., Ltd. in distributing ROSA since they distributed CUL's VOCALOID3 packages in the past.[20]

ROSA's audition was launched on April 17. The illustration was confirmed to be released soon.[21] Details and scheduling for the audition were noted on ZAN-SHIN Co., Ltd.'s official website for ROSA.[22] A preview of ROSA's face was shown on April 20.[23][24] On April 28, results of the first screening for the audition were revealed to be China Kitahara, Shirayuki, Juudenki, Minori Ninomiya, and Yuka Hiyamizu.[25][26] ROSA's lineart for both Synthesizer V and CeVIO AI were revealed on May 1 and the colored sketches (rough illustrations) were released on May 4.[27][28]

On May 8, Shirayuki was confirmed to be the chosen voice actress.[29] Recording sessions for ROSA began on May 14.[30] On May 15, Yoshida Iyo was confirmed to be the illustrator and the final artwork was shown.[31] Information about ROSA's crowdfunding campaign in collaboration with SSS LLC. was revealed and was confirmed to run from June 1 to June 30 on GREENFOUNDING. The production project for ROSA's CeVIO AI talk voicebank would begin afterwards and the project's page would be published as soon as it was ready. At that time, ZAN-SHIN was considering a system that would allow overseas fans to participate. The release order was confirmed to be the following: Japanese CeVIO AI Talk, Japanese Synthesizer V AI, English CeVIO AI Talk, and English Synthesizer V AI.[32]

The start date for the crowdfund campaign was later changed to June 3 and procedures for overseas investors were being worked upon, but was confirmed that this may be delayed.[33] The goal was set to 7 million yen.[34] The crowdfund for ROSA's CeVIO AI Talk voicebank began on June 3 with six tiers for Japanese supporters and three tiers for overseas supporters. A sample of Shirayuki voice-acting as ROSA was made available in the campaign to give supporters an idea of what ROSA may sound like prior to creating her voicebank.[35] The CeVIO AI voicebank was fully funded on June 30, with only a few hours before the campaign's end, resulting in being 112% funded.[36] Test recordings of the voicebank began on July 22, with ZAN-SHIN fully focusing on the production of the CeVIO AI Talk voicebank at this point in time.[37]

Voice Database Information[]


There are currently no demonstrations of ROSA's voice database.

Voice Libraries[]

  • ROSA Talk Voice (CeVIO AI), In development
  • ROSA AI (Synthesizer V Studio), In development
  • ROSA English Talk Voice (CeVIO AI), In development
  • ROSA English AI (Synthesizer V Studio), In development

Additional Information[]





External links[]