# Kotonoha Akane/Aoi

Kotonoha Akane & Aoi (Japanese: 琴葉茜・葵) are a pair of Japanese VOICEROID+ voicebanks released 25 April 2014. They were produced by AI, Inc. using AITalk [ja] and distributed by AH-Software, with voiced by Yui Sakakibara.

## Development

| Year | Software | Voicebanks | Engine | Application | Operating system |
| Text-to-speech ||||||
| 2014 | Kotonoha Akane & Aoi (VOICEROID+) | — | AITalk 3 | — | Windows |
| 2017 | Kotonoha Akane & Aoi (VOICEROID2) | Kotonoha Akane Kotonoha Aoi | AITalk 4 | Voiceroid 2 | Windows |
| 2020 | Kotonoha Akane & Aoi (A.I.VOICE) | Kotonoha Akane Kotonoha Aoi Kotonoha Akane Tsubomi Kotonoha Aoi Tsubomi | AITalk 5 | A.I.Voice Editor | Windows |
| 2021 | A.I.Voice Kotonoha Akane & Aoi English | Kotonoha Akane (English) Kotonoha Aoi (English) | Un­known | A.I.Voice Editor | Windows |
| 2022 | Kotonoha Talk Chinese | Kotonoha Akane（Chinese） Kotonoha Aoi（Chinese） | Un­known | A.I.Voice Editor | Windows |
| 2023 | Kotonoha Akane & Aoi (A.I.VOICE2) | Kotonoha Akane (NV) Kotonoha Akane Tsubomi (NV) Kotonoha Aoi (NV) Kotonoha Aoi Tsubomi (NV) | AITalk 6 | A.I.Voice 2 Editor | WindowsmacOS |
| Singing voice synthesis ||||||
| 2020 | Kotonoha Akane & Aoi (Synthesizer V Studio) | Kotonoha Akane & Aoi | Synthesizer V Standard | Synthesizer V Studio | LinuxmacOSWindows |
| 2022 | Kotonoha Akane & Aoi Song Library (NEUTRINO) | Kotonoha Akane Kotonoha Aoi | Un­known | Neutrino | Google ColaboratorymacOSWindows |
| Voice conversion ||||||
| 2021 | Kotonoha Akane & Aoi Voice Model for Voidol | Kotonoha Akane Kotonoha Aoi | R.C.voice | Voidol | iPadOSiOSmacOSWindows |
| 2022 | Kotonoha Akane & Aoi (Seiren Voice) | Kotonoha Akane & Aoi | Un­known | Seiren Voice | Windows |

### Text-to-speech

Kotonoha Akane & Kotonoha Aoi's VOICEROID+ voicebank was distributed by AH-Software and released on 25 April 2014. The VOICEROID2 voicebank released on 9 June 2017, added a Voice Style feature.
On 22 February 2020, a text-to-speech synthesizer software A.I.VOICE [ja] released the product "A.I.Voice Kotonoha Akane & Aoi", added two voicebanks with younger voices, Kotonoha Akane Tsubomi and Kotonoha Aoi Tsubomi. The English version released on 10 December 2021 and Chinese on 22, September, 2022.

### Singing voice synthesis

Kotonoha Akane & Aoi's shared singing library for Synthesizer V [ja] Studio produced by AH-Software released on June 26, 2020. The recommended rhythm is between 70 and 180 bpm, and the recommended range is between E3 and D5. The included scales are G ♯ 3, C ♯ 4, F ♯ 4, and C5 (falsetto).
The NEUTRINO [ja]'s Kotonoha Akane & Aoi singing voice library have been available for free to users who purchase "A.I.Voice Kotonoha Akane & Aoi" since 25 April 2022. The recommended range for Kotonoha Akane is between mid1G and hiC (G3 to C5), with a recommended rhythm of 120 to 180 bpm, and the recommended genres are rock, pop music, etc.; The recommended range for Kotonoha Aoi is between mid1G and hiC (G3 to C5), with a recommended rhythm of 80 to 140 bpm, and the recommended genres are pop, folk music, etc.

### Voice conversion

The voice model library of Kotonoha Akane & Aoi for an AI voice conversion application Voidol was produced by Crimson and released on 12 October 2021. Released on 17 May 2022, the voicebank of Kotonoha Akane & Aoi for a voice conversion software Seiren Voice was produced by Dwango.

## Character

Kotonoha Akane & Aoi's character art were designed by Japanese illustrator Yoshida Yoshitsugi. They are a pair of twin sisters.
Akane is used to speaking in the Kansai dialect for she lived in Kansai region for a long time, and Aoi has standard intonation. Akane is "outgoing and cheerful" while Aoi is "calm and reliable".