KAFU

**This project is currently in production.**
According to official sources, this project was announced to currently be in production or is in its conceptual stages.
Please read the page for more information.

## Additional Product Information

### Affiliations

* Dreamtonics Co., Ltd.
* AH-Software Co. Ltd.

### Catalog No.

* KTR-0119 (Starter Pack)
* KTR-0120 (standalone)

### Product Page

**Physical copies**:* FINDME STORE (pre-order)
* FINDME STORE (Starter Pack; pre-order)
* Amazon Japan (pre-order)
* Amazon Japan (Starter Pack; pre-order)

## Examples of Usage

### List of Songs

* VocaDB
* Voice Synthesizer Lyrics Wiki

**KAFU** (可不) is an upcoming Japanese vocal to be developed by AH-Software Co. Ltd. and distributed by KAMITSUBAKI STUDIO, and is expected to release as an AI voice database for *Synthesizer V Studio* in January 2024. She was originally released as a Song Voice for the *CeVIO AI* engine in July 2021. She is part of the Musical Isotope Project.

She is voiced by KAF, a Japanese virtual singer (VTuber) and performer.

## Concept

KAFU is advertised as a "Musical Isotope" (音楽的同位体) of KAF, likely done in a way to separate the voice synthesizer character from the virtual singer.

Her signature color is blue, specifically hex code #0000FF.

### Etymology

KAFU's name is a combination of "KAF", her voice provider, and "You", stylized as "U".

The kanji of her name, "可不" (KAFU) derives from "kanousei" (可能性) meaning "possibility," and "fukakai" (不可解) meaning "mysterious, incomprehensible." It was taken from the first character of each word respectively ("可"能性 and "不"可解; "ka"nousei and "fu"kakai.) In addition, "Fukakai," or "Incomprehensible" is a song sung by KAF, and it is one of her more notable songs.

Additionally, the name "KAFU" shares its romanization with KAF's character "Morisaki Kafu" (森先化歩) from KAMITSUBAKI CITY UNDER CONSTRUCTION. (神椿市建設中。) So far, this trait is also shared by the other characters in the Musical Isotope Project.

KAFU's full title is also known as "Musical Isotope KAFU" (音楽的同位体 可不).

### Appearance

KAFU's appearance and theme are based on her voice provider, KAF, with many similar design elements and an overall white color-scheme, which was a recurring required design choice within the Musical Isotope Project.

KAFU's Synthesizer V release reused the same design as her previous CeVIO AI version. She wears a heavy white jacket with blue and black detailing and a hood similar to that of KAF's own attire. She also wears an over-the-knee length black dress, white tights, yellow socks, and blue-heeled short boots. Her hair is snow white and bobbed with low pigtails on either side, reminiscent of KAF's hairstyle, and is adorned with large diamond-shaped hair clips. Her eyes are dark blue and purple.

1st reference sheet by PALOW2nd reference sheet by PALOW
### Relations

* KAF - voice provider and basis for KAFU's character.
* SEKAI - Fellow "Musical Isotope Project" vocal.
* RIME - Fellow "Musical Isotope Project" vocal.
* COKO - Fellow "Musical Isotope Project" vocal.
* HARU - Fellow "Musical Isotope Project" vocal.

## History

In October 2020, KAFU, a voice synthesizer character based on and voiced by virtual singer (VTuber), KAF, and illustrated by PALOW, was announced to be in production for CeVIO AI. KAFU's final voice was determined by KAF while taking account of the results from a questionnaire (showcasing voices "TYPE // A", "TYPE // B", and "TYPE // C" respectively), with KAF noting that while she was overall thrilled of the vocal as a VOCALOID fan herself and she had no concerns of KAFU "replacing" her, she felt as though some people looked at the two as inseparable entities that were indistinct from each other, prompting her to choose "TYPE // B" as the vocal to proceed with development. After some delays due to the need to satisfy both KAF and fans, CeVIO AI KAFU released on July 7, 2021.

### 2023

On July 7, 2023, at the end of the "V.I.P -Virtual Isotope Phenomenon- 1st" livestream, it was announced that KAFU would be in development for Synthesizer V AI and was expected to release in winter 2023. On July 10, AH-Software Co. Ltd. confirmed that they would be developing KAFU though would not be publishing her themselves as this would be fulfilled by KAMITSUBAKI STUDIO. On September 3, pre-orders were confirmed to begin the next day at 18:00 JST.

On September 4, pre-orders for KAFU's physical packages were opened and would run until November 27 at 12:00 JST or if the available stock had sold out as she is a made-to-order product. She would be made available again depending on the number of products that could be produced, which KAMITSUBAKI STUDIO would announce on their official LINE account. KAFU's voice database could be purchased on its own or as a starter pack paired with the Synthesizer V Studio Pro editor. Her release date was confirmed to be January 15, 2024.

On December 23, KAMITSUBAKI announced that her release date was being postponed due to various unspecified circumstances, with new release date being yet undetermined but to be announced as soon as details are decided. Pre-orderers were given the option to cancel their reservations due to the postponement, being instructed to contact the stores where they placed their preorders.

## Voice Database Information

### Voice Databases

Product Information
**Versions**

  **Lite Version/FLT Available?:** TBA  **Starter Pack Available?:** Yes (Pre-order)  **Web Version Available?:** No
**Package details** as noted:

KAFU is a feminine Japanese voice database based on the singing style of KAF. As expected of an AI voice database, KAFU is capable of singing with a more human-like and realistic voice.
**Vocal traits** as noted:

With Diffusion Probabilistic Models (DPM), KAFU can sing more realistically through changes in volume and breath, further enriching singing details, making each singing unique, and providing creators with more options. Through this mode, she can use AI Retakes to create multiple "takes" of a sung section to find an ideal vocal without the need for "laborious tuning". This feature is only available in the Synthesizer V Studio Pro Editor.
**Phonetic notes** as noted:

* Phoneme format: Romaji
* Through Cross-lingual Singing Synthesis, KAFU is expected to sing in not only Japanese but also in English, Mandarin Chinese, and Cantonese Chinese. This feature is only available in the Synthesizer V Studio Pro Editor.

**Vocal Modes** as noted (Synthesizer V Studio Pro Editor only):

* KAFU comes with four variations:
	+ Emotional
	+ Kawaii
	+ Stylish
	+ Powerful

**License agreements** as noted:

* KAMITSUBAKI STUDIO's Secondary Creation Guidelines - Japanese

**Voice database sample**

* KAFU Solfège:
File:KAFU Solfege.ogg
		File:KAFU Emotional.ogg
		- "Kawaii":
		File:KAFU Kawaii.ogg
		- "Stylish":
		File:KAFU Stylish.ogg
		- "Powerful":
		File:KAFU Powerful.ogg

## Voice Libraries

* KAFU Song Voice (*CeVIO AI*), July 7, 2021
* KAFU AI (*Synthesizer V Studio*), in development

## Additional Information

### Marketing

Throughout her time as a CeVIO AI vocal, KAFU had received official albums and merchandise. She was featured in live performances, including duets with her voice provider KAF, and was shown at the KAMITSUBAKI EXHIBITION, where various works like music videos and illustrations were on display. Since November 17, 2021, works featuring KAFU were accepted on Piapro, a well-known Japanese center of the VOCALOID, and extensively, voice synthesizer community.

### Reputation

KAFU's character status
**Reaction**

As a CeVIO AI vocalist, KAFU became overwhelmingly popular and may be considered as one of the most notable CeVIO vocalists to date, with usages of over 7,000 songs at the time of the announcement of her Synthesizer V AI in July 2023. Regarding her Synthesizer V AI announcement, she was met with surprise and excitement among fans.
**Miscellaneous**

KAFU's development for Synthesizer V AI was announced on July 7, 2023, coinciding with her second anniversary since her CeVIO AI release on July 7, 2021.
**Achievements**

* First Synthesizer V from KAMITSUBAKI STUDIO.
* First female Synthesizer V from KAMITSUBAKI STUDIO.

## References

1. ↑ https://twitter.com/ahsoft/status/1678238243253551105
2. ↑ https://twitter.com/PIEDPIPER2045/status/1318155734920564736
3. ↑ https://twitter.com/uncreepy\_studio/status/1314947462612889600
4. ↑ https://kaf-u.kamitsubaki.jp/ - Color from logo seen throughout the official website.
5. ↑ https://twitter.com/virtual\_kaf/status/1318145530577395718
6. ↑ https://twitter.com/kaf\_you/status/1440592894969008135
7. ↑ https://www.youtube.com/watch?v=y1nyhLn2QdY
8. ↑ https://twitter.com/musicalisotope/status/1677284636215623681
9. ↑ https://twitter.com/ahsoft/status/1678238243253551105
10. ↑ https://twitter.com/musicalisotope/status/1698319934567157812
11. ↑ https://twitter.com/musicalisotope/status/1698623590655201624
12. ↑ https://twitter.com/musicalisotope/status/1738363800066355499
13. ↑ https://twitter.com/kamitsubaki\_jp/status/1465878382428655619
14. ↑ https://ch.piapro.jp/creator/2021/11/f2111191-1
15. ↑ https://forum.synthesizerv.com/t/topic/9439/2 - Statistic as noted by fan @claire on Synthesizer V Forums