Hi,   I don't think so.   OK you downloaded the addon,   the voices
you might want to use,   install the addon first,   do not reboot nvda
yet,  install all voices you might use then restart nvda and you
should see the sinth under the sinth settings page select Rh Voice as
the sinth then select the voice if it doesn't show up I do not know
why. using alpha and stable as well and the addon and voices work.

On 26/09/2019 23:34, Richard Wells wrote:

I tried this using the English add-on and the three offered English
voices. They installed, but they do not show in the change synthesizer
dialog under settings/speech. Did I miss a step somewhere?