This depends on what version of Vocaloid you are getting. If you are getting Vocaloid 1 or Vocaloid 2 then yes you do require the full editor. However, each Vocaloid 1 and Vocaloid 2 voice bank comes with the editor. Vocaloid 3 on the other hand does not require the full editor to use but is very limited. Each Vocaloid 3 voicebank will include what is known as a tiny editor that will only allow up to one track to be used while the full editor uses 16, the tiny editor will only allow you to make 17 measure of music while the full editor will allow for 999, the reverb effect will be usable in the tiny editor but the full editor while have reverb, compression, and VST compatibility, and Finally the tiny editor will not allow Vocaloid 2 voice bank import while the full editor will.