Dr. Hertz is President and Chief Scientist of NovaSpeech LLC. She has more than thirty years experience in multi-language text-to-speech synthesis, including both text analysis and speech generation, and both rule-based and concatenative methods. She has extensive business, technical, and research experience in these areas, and a strong background in speech processing, linguistics, acoustic phonetics, speech perception, software development, and software optimization.
In 1983, Dr. Hertz founded Eloquent Technology, Inc. (ETI), a text-to-speech software company, and transformed it over a number of years from a basement operation into a profitable, worldwide leader in multi-language text-to-speech technology.
As President and Chief Technology Officer at ETI, Dr. Hertz oversaw all of the company’s technical and business operations throughout its seventeen-year existence, and she invented or designed much of its core technology. This technology included the multi-voice ETI-Eloquence text-to-speech system for thirteen languages/dialects and the sophisticated Delta programming language and interactive environment used to develop the ETI-Eloquence synthesis rules. The ETI-Eloquence product was known for its extremely small memory footprint, flexibility, its exceptionally accurate text processing, and its consistent and intelligible speech output.
In January 2001, Dr. Hertz sold Eloquent Technology, Inc. to SpeechWorks International, Inc. (now part of Nuance Communications, Inc.). ETI-Eloquence is still marketed today by Nuance, and is the leading text-to-speech software for blind users worldwide. See ETI's Smithsonian Speech Synthesis History Project (SSSHP) page for more details on ETI's history and technology, and the narrative by Sue Hertz on the SSSHP site for a personal account of the events that led to ETI's formation.
After the ETI-SpeechWorks merger, Dr. Hertz worked for a year and a half in the SpeechWorks Ithaca office as Chief Scientist and Executive Director of text-to-speech technologies. Since 1979, she has also held positions in the Linguistics Department at Cornell University. She is currently an Adjunct Professor in the department, teaching occasional graduate-level courses in speech synthesis and phonetics. In addition, she has been the Principal Investigator or Project Director on 14 government grants or contracts in the area of speech synthesis.
Dr. Hertz has conducted or overseen many research projects in text analysis, multi-language speech synthesis, speech perception, phonetic model development, and the phonology/phonetics interface. In the area of speech synthesis, she has designed or developed a number of sophisticated models and algorithms for both text analysis and speech generation, including those underlying the language-universal and language-specific components of the ETI-Eloquence synthesis system—see Hertz et al. (1999). See Cornell's and ETI's SSSHP pages for more information on these projects.
In 2000, Dr. Hertz discovered that many segments in natural speech can be replaced with formant-synthesized ones with little if any degradation in speech quality, naturalness, or intelligibility—see Hertz (2002). NovaSpeech was founded to explore this finding in more detail, and these explorations have resulted in the company's novel hybrid speech synthesis system (see projects).
Another of Dr. Hertz's current research interests is the development of a model that accounts for how listeners parse the continuous speech stream into linguistic units like phonemes, syllables, and words. This model has not only provided an important framework for NovaSpeech's hybrid synthesis system, but also promises to advance other areas of speech processing, such as speech recognition.
In her other life, Dr. Hertz is an artist, painting landscapes and people in oils--see www.suehertzfineart.com. As explained on her art site, she is fascinated by the similarities in how visual and auditory stimuli are parsed into meaningful objects, be they particular kinds of trees or specific words.