Kagamine Rin/Len VOCALOID2 act2 Append VOCALOID4 English

This is an article about the Kagamine Rin and Len V4 English software for the VOCALOID4 engine.



At NYC Con, it was mentioned that Crypton Future Media was focusing on updating and creating English voicebanks for all of their VOCALOIDs.


On October 30, 2015, Crypton Future Media updated the Kagamines' page, revealing the silhouette and showcasing a demo for their Japanese vocals. There was also a separate page for their English voicebanks which confirmed that the package would be sold on its own and as a bundle with their Japanese voicebanks.[1] According to the product page, these voicebanks were expected to release on December 24.[2]

In December, it was stated they were ready for the first English demo. The demo was delayed due to the English installer was being done after the Japanese one was finished.[3]

Product InformationEdit

Demonstration songsEdit


スターストラク / Starstruck (Rin and Len V4X English) Niconico YouTube

Recommended Edit

  • Hard Disk Capacity:
    • Windows:
      • More than 6GB (NTFS format)
    • Mac:
      • More than 6GB (HFS+ format)
  • Other: Kagamine V4 English is a voice library add-on. To use it you need a vocal editor, like VOCALOID4 or Piapro Studio.
  • Internet connection.

For more technical information, see Kagamine Rin/Len V4X.

Voicebank LibrariesEdit

Product Information
  Trial/Demo Vers?: No  Starter Available?: No
Package details
This is the English version of the Kagamine product. Like the original Japanese vocals, the English version supplies a pair of vocals for male and female intended roles within music.

This package comes with Piapro Studio.

Vocal traits as noted:
  • GWL capable
  • Provides an additional language for both libraries that allows them to produce results that weren't possible with the Japanese package.
  • They both have the same tempo and can cover the same genres. Due to the fact they came from the same voice provider, their overall vocal weights and traits are also similar enough to make for easy harmonization, though this could end up giving too similar results even if using them separately, limiting their versatility.
Software issues as noted:
  • The vocals' intended counterpart in the Japanese V4 package are the two "power_EVEC" vocals. However, the tempo range of the English versions are much smaller, limiting the genres the pair can do easily.
    • Increasing the brightness and clearness of the vocals may help their English to match their Power voicebanks tone better. However, this still does not result in a perfect match because of the fact the original raw samples don't have a nature enough like the Japanese "Power" vocals. In short, their default nature will not change even if the tone does.
  • Another reason why their English does not sound like their Japanese is due to the fact that the voicebanks are missing the clear and crisp sound.
  • Another issue with the tempo range is how limiting the product is overall. Outside of the "Power" vocals from Kagamine Rin/Len Append, the two have never had the same tempo. This limits how much separation the two vocals have from each other.
  • As with most other Crypton Future Media English vocals, both have a notorious Japanese accent.

Individual vocalsEdit

Product Information
  Optimum Tempo: 55~155BPM  Optimum Range: G2~B3
  Total Tempo (min-max): 100BPM  No. of Keys: W=10, B=7, Total=17
Package details
Described by Crypton as a young female voice database with brisk, natural pronunciation and singing voice quality.
Vocal traits as noted:
  • Compared to Len, she is sharper sounding and less muffled.
  • Maintains the particular timbre Rin has with a stable performance in low and high notes.
  • She lacks the power of her Japanese vocals.
Software issues as noted:
  • This vocal is much softer than the original Japanese tone; in consequence, there's no match for it in the Japanese package. The closest in tone is her "Warm" append, but the differences in ranges and tempos will still give a very obvious change when switching languages.
Voicebank sample

Rin V4 English Sample


Product Information
  Optimum Tempo: 55~155BPM  Optimum Range: E2~G#3
  Total Tempo (min-max): 100BPM  No. of Keys: W=10, B=7, Total=17
Package details
According to Crypton, this voicebank offers a young modest male voice database that sings in English with natural pronunciation and voice quality.
Vocal traits as noted:
  • Provides a vocal that covers a younger masculine role.
  • Compared to Rin, Len is muffled and unclear.
  • He lacks the power of the Japanese vocals.
Software issues as noted:
  • As a female vocalist was behind his vocal, Len's vocal actually represents a lower female vocal range like other Vocaloids such as YANHE or Ryuto. This is a issue that concerns even the Japanese version of his vocals.
    • However, the English version of Len suffers from having almost no timbre in the voice at all. This makes it very feminine sounding compared to the Japanese vocal.
    • According to many users, the root of the problem with his voice is that some samples are almost identical to Luka V4x English voicebank "Straight", and certain sounds are similar in tone and pronunciation so Len can easily switch to the "Luka-esque" tones randomly without warning.[4]
Voicebank sample

Len V4 English Sample



  1. Rin and Len English homepage
  2. product page
  4. link