An alternative (and complement) to human narration, and the associated costs of creating and distributing it, is speech synthesis—when done right, that is. The mere thought of synthesized speech is enough to make some people cringe, though, as it’s still typically equated with the likes of poor old much-maligned Microsoft Sam and his tinny, often-incomprehensible renderings. Modern high-end voices are getting harder and harder to distinguish as synthesized, however, and the voices on most reading systems and computers are getting progressively more natural sounding and pleasant to the ears for extended listening.
But whatever you think of the voices, the need to be able to synthesize the text of your ebook is always going to be vital to a segment of your readers, especially when human narration is not available. It’s also generally useful to the broader reading demographic, as I’ll return to.
And the voice issues are a bit of a red herring. The real issue here is not how the voices sound but the mispronunciations the rendering engines make, and the frequency with which they often make them. The constant mispronunciation of words disrupts comprehension and ruins reading enjoyment, as it breaks the narrative flow and leaves the reader to guess what the engine was actually trying to speak. It doesn’t have to be this way, though; the errors occur because the mechanisms to enhance default synthetic renderings haven’t been made available in ebooks, not because there aren’t any.
But to step back slightly, synthetic speech engines aren’t inherently riddled with errors, they just fail because word pronunciation can be an incredibly complex task, one that requires more than just the simple recognition of character data. Picture yourself learning a new language and struggling to understand why some vowels are silent in some situations and not in others, or why their pronunciation changes in seemingly haphazard ways, not to mention trying to grasp where phonetic boundaries are and so on. A rendering engine faces the same issues with less intelligence and no ability to learn on its own or from past mistakes.
The issue is often sometimes as simple as not being able to parse parts of speech. For example, consider the following sentence:
An official group record of past achievements was never kept.
A speech engine may or may not say “record” properly, because record used as noun is not pronounced the same way as when used as a verb in English.