DECtalk
DECtalk was a speech synthesizer and text-to-speech technology developed by Digital Equipment Corporation in 1984,[1] based largely on the work of Dennis Klatt at MIT, whose source-filter algorithm was variously known as KlattTalk or MITalk.[4][5]
![]() DECtalk DTC01 (with a cat for scale) | |
Developer | Digital Equipment Corporation |
---|---|
Type | speech synthesizer, text-to-speech |
Release date | 1984[1][2] |
Introductory price | DCT01 US$4,000 (equivalent to $9,844 in 2019)[3] |
Connectivity | RS-232C serial interface[1] |
Platform | Platform: Windows NT, Alpha with Digital UNIX |
Dimensions | (DCT01 = W 45.7mm x D 30.48 mm x H 10.16 mm ( 18in x 12in x 4in) ) |
Mass | (DCT01 = 7.2 kg (16 lbs)) |
About
The first DECtalk units were seen in 1984. They were standalone units that connected to any device with an asynchronous serial port. These units were also able to connect to the telephone system by having two telephone jacks. One connected to a phone line, the other to a telephone. The DECtalk units could recognize and generate any telephone touch tone. With that capability the units could be used to automate various telephone-related tasks by handling both incoming and outgoing calls. This included acting as an interface to an email system and the capability to function as an alerting system by utilizing the ability to place calls and interact via touch tones with the person answering the phone.
Later units were produced for PCs with ISA bus slots. In addition, various software implementations were produced, most notably the DECtalk Access32. Certain versions of the synthesizer were prone to undesirable characteristics. For example, the alveolar stops were often assimilated as sounding more like dental stops. Also, versions such as Access32 would produce faint electronic beeps at the end of phrases.
In the final years of DEC, early/mid-2000,[6] the DECtalk IP was sold to Force Computers, Inc. In December 2001, the IP was sold[7] from Force Computers, Inc, to Fonix Speech, Inc. (now SpeechFX, Inc.), which offers DECtalk as a small-footprint TTS system and in a computer program form.[8]
Features
DECtalk had a number of built-in voices which were identified by the following names: Perfect Paul (the default voice), Beautiful Betty, Huge Harry, Frail Frank, Kit the Kid, Rough Rita, Uppity Ursula, Doctor Dennis and Whispering Wendy. Each of the voices were editable by adjusting various parameters (such as throat size, crossover frequencies, etc.)
DECtalk understood phonetic spellings of words, allowing customized pronunciation of unusual words. These phonetic spellings could also include a tone indicator which DECtalk would use when enunciating the phonetic components. This allowed DECtalk to sing.
Uses
- The DECtalk engine was notably used in the US National Weather Service's first "Console Replacement System" (CRS) installations in the late 1990s for NOAA Weather Radio. As of 2003 it had all but been replaced by a far more modern engine called Speechify from SpeechWorks (not to be confused with the iOS app of the same name).[9] DECtalk's Perfect Paul preset voiced station identifications on many NWR stations until the CRS was replaced by a new system, called the "Broadcast Message Handler" (BMH), in 2016.[10]
- One of the early uses was a "text to voice" system that read an individual's emergency medical information (medications, allergies, doctor, insurance and contact info stored in a database) to hospitals telephoning in about patients presenting at emergency rooms. The company, Med-Fax, created by David Grober in 1986, used the DECtalk on an IBM platform, making it one of the early cross platform applications (DEC to IBM).
- DECtalk can be used as part of a speech generating device for those unable to speak. A notable user was Stephen Hawking, who was unable to speak due to a combination of severe disabilities caused by ALS as well as an emergency tracheotomy.[11] Hawking used a version of the DECtalk voice synthesizer for several years[12] and came to be associated with the unique voice of the device. In 2011, Hawking's research assistant Sam Blackburn said Hawking still used a version of DECtalk identified on its board as the "Calltext 5010" manufactured in 1988 by SpeechPlus, Inc.,[13] because he identified with it and had not heard a voice he liked better. The CallText 5010 was still listed on Hawking's site as of 2015.[14] A team from Cambridge (UK) and Palo Alto eventually emulated the workings of the CallText 5010 on a Raspberry Pi, which Hawking used from January 2018 to his death in March of that year.[15]
In popular culture
- The character "Dee Klatt" from Chipspeech was based on data from this device.[16]
- In the sixth episode of Tales from the Darkside, Mookie and Pookie, the voice of Kevin "Mookie" Anderson is created with a DECtalk.
- The video game Moonbase Alpha uses a software version of DECTalk for chat text.
References
- DECtalk lets micros read messages over phone, By Peggy Zientara, InfoWorld, Jan 9-16, 1984, Page 21 and 23, ...DECtalk, which the company says will be available in March at a price of $4000...The DECtalk hardware, which fits easily under a 12-inch monitor...The unit attaches to a personal computer via an RS-232C serial interface...
- Advertisement:We just turned every touch-tone phone into a financial clearinghouse., Computerworld, 18 Feb 1985, Page 39
- Advertisement: INTRODUCING DECTALK THE REVOLUTIONARY NEW TERMINAL THAT LETS YOUR COMPUTER SPEAK FOR ITSELF., Computerworld, 23 Jul 1984, Page 70-71, ...The DECtalk system is available now for $4000* or less depending on quantity...
- Klatt, Dennis (April 1987), "How Klattalk became DECtalk: An Academic's Experiences in the Business World", The official proceedings of Speech Tech '87, New York: Media Dimensions Inc./Penn State, pp. 293–294
- Computer talk: amazing new realism in synthetic speech, By T. A. Heppenhemimer, Popular Science, Jan 1986, Page 42 and 44 and 48, ..with the creator of DECtalk, Dennis Klatt...Ironically having given computers the power of speech, he slowly losing his own...DECtalk - actually a micro computer itself -...
- "AllLinuxDevices: Force to Support Linux On DECtalk TTS For Strongarm and Intel Devices". Linux Today (Press release). 2000-10-26. Retrieved 2012-09-16.
- "Fonix acquires DECtalk from Force Computers". Deseret News. 2001-12-21. Retrieved 2012-09-16.
- "SpeechFX Text to Speech Solutions, FonixTalk, DecTalk". SpeechFX, Inc. Retrieved 2012-05-25.
- "Voices Used in NOAA Weather Radio". Archived from the original on 2008-02-06.
- US Department of Commerce, NOAA. "New NOAA Weather Radio Management Platform is Coming Soon". www.weather.gov. Retrieved 2019-05-05.
- Hawking, Stephen. "Stephen Hawking and ALS". Retrieved 2009-08-10. (Originally published as: Hawking, Stephen. "Disability - my experience with ALS". hawking.org.uk. Archived from the original on 2000-06-14.)
- Greenemeier, Larry (2009-08-10). "Getting Back the Gift of Gab: NexGen Handheld Computers Allow the Mute to Converse". Scientific American. Retrieved 2009-08-10.
- Lange, Catherine de (2011-12-30). "The man who saves Stephen Hawking's voice". New Scientist. Retrieved 2013-06-09.
- Hawking, Stephen. "The Computer". hawking.org.uk. Retrieved 2015-03-01.
- Fagone, Jason. "The quest to save Stephen Hawking's voice". sfchronicle.com. Retrieved 2018-03-20.
- "Plogue - chipspeech :: Vintage speech synthesizer". PLOGUE - Music Software - Developers. Retrieved 2016-04-27.
External links
- Klatt's Last Tapes - History of Speech Synthesis. BBC Radio 4 program (voice with slides). (see also: full transcript, archive link)
- OpenVMS Notes: DECtalk Model numbers.
- NMAH: Smithsonian Speech Synthesis History Project: A Brief History of DECtalk