I haven't tried Tortoise, thanks for pointing me to it.
The voices were cloned by fine tuning a VITS model with coqui.ai. I used about two hours of speech for each speaker. With more time and resources, I'm certain it's possible to make those voices considerably better.
It was fine tuning, so the process was a lot faster than I originally anticipated. I'd say it was between 36 and 72 hours for each voice. I have been working on a gradient notebook provided by Paperspace, which guaranteed me A6000 instances (48GB GPU RAM) at a reasonable flat rate. I discovered them after being repeatedly frustrated by the random allocation of GPUs on colabs pro+ plan.
