OKI Starts Shipping Samples of High-quality Speech LSIs

Improvement of hearing experience by adjusting playback speed and tone
Oki Electric Industry Co., Ltd. (TSE: 6703) today announced it has developed the “ML2272X Series” speech-synthesis LSIs that enable users to adjust playback speed and speech tone. While the speech tone, or pitch, in previous speech-synthesis devices increased or decreased as the playback speed changed, with these new devices, users can adjust both the speed and tone. Because the chip is equipped with a 16-bit audio-class D/A converter, it also offers high voice quality compared to previous OKI speech-synthesis LSIs. Samples of the product will be shipped today and volume shipment is scheduled to start in June 2008.

“With OKI’s ML2272X Series, users can now offer more user-friendly products --such as language learning devices, electronic dictionaries, educational toys and products for the elderly -- by integrating voice guidance features into these products,” said Masahiko Morioka, President of Silicon Solutions Company at OKI. “As a leader in the field of speech-synthesis LSIs, OKI will continue to leverage its total support expertise and proprietary speech technology such as OKI-ADPCM(*1), and technical knowledge it has gained for over 20 years with a focus on voice quality, to provide speech solutions that offer added value.”

Speech functions are used in a variety of user-friendly products, such as for voice guidance in high-end white goods, home appliances and alarm systems. Instead of a buzzer, voice guidance is used to notify users when a certain task has been finished or to alert and warn them in a dangerous situation. This allows children and the elderly to be aware of the situation.

Conventional speech for voice guidance is recorded at a certain predefined tone, which makes it difficult to adapt the playback voice to the situation or environment. In addition, people hear voice guidance differently depending on their age or the environment and situation they are in at that time (quiet, loud, open space, etc).

The newly developed ML2272X Series can adjust the tone or speed of the voice in such voice guidance applications depending on the situation. For example, for emergency situations where urgency is needed, the tone and speech of the voice should be different from situations where calm action is required. As an additional example, the elderly tend to hear low pitch sounds better, thus in home appliances a high-pitched voice of 4kHz or more can be changed to a slow and low pitch voice for better hearing.
The ML2272X Series

Compared to OKI’s previous voice LSI products, the voice quality of ML2272X Series is notably improved. Also, by including a speaker amplifier, OKI has made it easy for customers to incorporate voice playback functionality in their products. Moreover, the built-in memory has been increased to a maximum of 16Mbit, making it possible to record and play back an increased number of messages.
* P2ROM is a trademark of Oki Electric Industry Co., Ltd. in Japan.
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