The model cards list all of our data sources. They are all publicly available datasets that are commonly used in training most speech recognition models. It is good to take a wide variety of domains for robustness. Clean speech vs noisy backgrounds. Prepared speech vs spontaneous speech. Studio microphones vs cheap laptop microphones. More exposure is better.
For raw number of hours, I would set a goal of 40k hours. That number worked well for us, although if you are training bigger models you might still benefit from more.
For raw number of hours, I would set a goal of 40k hours. That number worked well for us, although if you are training bigger models you might still benefit from more.