When you upgrade to Speechdio PRO, you get the following PRO features in your Speechdio account:
1. 213 more voices in your Speechdio account.
2. Access to dialog feature where you can use multiple voice-overs in a single file to create a dialog.
3. Ability to merge speech files.
4. Ability to create 4X longer speech files. Which means you can use up-to 3200 words in a single script.
5. 400 more background musics in your Speechdio account.
6. Ability to import text from URL to use as script for your speech files.