Vocalizer Expressive Driver is a speech synthesizer that is designed to work exclusively with the NVDA screen reader (Non Visual Desktop Access). The package includes the Nuance Vocalizer Expressive speech synthesizer, which is a modern and natural-sounding speech synthesizer that is available in over 40 languages, comprising about 70 different voices in total. Each voice comes in many variants, ranging from "Compact" with small size and footprint, to "Premium High," which provides the best voice quality available, with larger sizes and footprint.

Features:

The Vocalizer Expressive package contains a custom NVDA speech driver that allows you to use the synthesizer directly from the screen reader, leveraging all the synthesizer performance and capabilities. You can install all the available voices and variants and use them in conjunction with the driver.

Some of the driver features include:

• Setting the voice to be used for speaking all screen reader messages, such as system controls, text documents, and web pages from the voices that are currently installed.
• Adjusting voice settings, such as volume, pitch, rate (speed), and voice variant.
• Spelling of text content.
• Reporting of uppercase characters, either with pitch changes or verbal announcements.
• Automatic language switching, which switches voices based on the language of the text to be spoken, when web pages and documents are properly marked (depending on installed voices).
• Direct communication from NVDA to the speech synthesizer, avoiding intermediary APIs such as SAPI, leveraging the best speed and integration and allowing for usage in portable contexts.

Requirements:

To use Vocalizer for NVDA, you need to be running NVDA version 2023.1 or greater. It is recommended to run the latest NVDA stable version, which can be downloaded from NVDA's downloads page or updated directly from NVDA's help menu. At least 1GB of memory is recommended to successfully run the synthesizer.

Depending on how many voices you wish to install, you will need sufficient free space on your hard disk or portable storage device. On some Windows systems, it is sometimes necessary to install the Microsoft Visual C Plus Plus Redistributable package to run Nuance Vocalizer.

This document assumes that you have basic familiarity with the NVDA screen reader and the Windows Operating system. It is strongly recommended that you check the extensive NVDA User Guide to get the most effective experience from this screen reader. The manual is also available under NVDA's Help menu.

Conclusion:

Vocalizer for NVDA is a powerful and versatile speech synthesizer that is specifically designed to work with the NVDA screen reader. It offers a wide range of voices in multiple languages, as well as advanced features such as automatic language switching and direct communication between NVDA and the synthesizer. Installing Vocalizer for NVDA is a straightforward process, and once it is installed and configured, it can greatly enhance the user experience for visually impaired users who rely on screen readers.