I think judging voicebanks from demo is like judging book from cover. Why don't people just try it themselves before give an opinion. Bashing vbs without even try is not cool.
It's must be individual phoneme samples as i suggested, because i can't control full phrase voice since vocaloid engine is already synthesized. Any change in pitch and timing will affect formants quality (it may sound thin/hollow or it doesn't sound like Luka anymore) this mean a standard pitch shifting doesn't work that well.By "voice sample," do you mean the full phrase, or individual phoneme samples?
I use a modified circuit Yamaha TG33 it's a 90s-ish Vector synthesis, although a custom build sy22 or an1x, sq80 is work too (or anything that have CPU inside it) but i don't even think about modding these synthesizer since these synth are the relics from the past right now and should be keep it true to the original unit.Also, how do you morph manually--Melodyne?
I can't argue with that, it simply fantastic. . . I always looking for Piano Sound Voice 1-14 factory preset when i use my motif xs8 rack.I think one very good thing about Yamaha keyboard/synths in general is their grand piano sound