This is an example of a new V4 feature called "Cross Synthesis", which allows the user to blend two voicebanks seamlessly, demonstrated here with IA and IA ROCKS. Note that IA DOES NOT have a V4 voicebank, this is a V3 VB put into V4 software.
I like this video it has multiple vocaloid people. Not sure if its already on here(last 1 i put on was lol) I like the song and how it was made. I didn't make it but its one of my favs on youtube.
