SVS

[MSQE43058402IF]

Singing voice synthesis... a title that has been around my head all the week.
The question is simple: Does anyone know some open source (or free) alternative to Cantai or ACEStudio that could work on a very old outdated computer (only for the CPU, an Intel Celeron 1037U because I use Windows 10)?
I have been trying OpenUtau, Diffsinger but the voicebanks are really bad, not the kind of voicebanks that I would need to synthesize operatic or lyric music, but almost all voicebanks are for pop, rock, blues, jaaz, etc.
If anyone knows something about this topic, please tell me.