Q. What is text-to-speech synthesis?
A. It is a technology which allows text that is stored electronicly to be converted directly into speech audio output.
Q. Why is this important for adaptive or assistive uses?
A. With text-to-speech and available quality third party applications: 1. A person who is blind or vision impaired can hear what they type and hear what is displayed on the PC monitor thereby allowing them nearly full use of the PC, 2. A person with a speech difficulty can have the synthesizer speak the text that they enter and act as their voice, 3. A person who has difficulty learning to read or write can use applications which integrate the display of text with the corresponding speech output to facilite the learning process.
Q. Where do I find out more information about third-party applications?
A. The section called "Applications" is accessible from this site's Home Page. The applications include DOS, Windows and OS/2 based screen access programs, "learning" programs, scanner text capture and reading programs, voice output programs, as well as a section of miscellaneous applications. There is also a section labeled "Related Products" which list products which incorporate a licensed version of DECtalk.
Q. What application do you recommend?
A. Most quality applications for a particular area are similar in features and functions. Most people select one over the other due to personal needs and preferences. Other factors include the kind of response they get from the vendor or whether local support is available. A suggested course of action is to select 2 or 3 vendors and talk to them about your needs and preferences and possibly get a demo copy.
Q. I'm blind and I want to use Windows. Is there anything I can use?
A. There are a number of "screen access" programs available today that support MS-Windows V3.x and Windows 95. Please refer to the "Applications" list accessible from the Home page for specific information on the vendors.
Q. Why is DECtalk text-to-speech (TTS) synthesis so well regarded?
A. With over 15 years of development, DECtalk TTS has acheived a very high level of intelligibilty as well as a sound which is "easy" on the user's ears.
Q. Why is the DECtalk hardware prices so much higher than other synthesizers?
A. The processing power needed to acheive the DECtalk's excellent TTS results require the use of two on-board processors, a multi-tasking real-time operating sytem, 1MB of on-board RAM, a digital-to-analog converter, special filtering circuits, an audio amplifier and an output speaker. The combined processing power of the DECtalk hardware is that of a 486/50 PC.
The combination of these product components, manufacturing in the United States and low volume output results in a relatively higher cost than other lower speech quality synthesizers or mass produced PCs. By comparison, the DECtalk Express costs/pricing is more in line with high end palm top PCs and the DECtalk PC2 pricing is comparable to high end video capture cards.
Q. I want to upgrade to DECtalk speech synthesis. Will the current version of my application work with it?
A. It is always best for the customer to check with the application vendor on the latest available version and what hardware it supports. Refer to the item "Applications" from the Home page for vendor contact info.
Q. Does Digital sell other assistive products?
A. We are not aware of any other assistive product sold by Digital. There are many other assistive products including braille printers, speech recognition, Optical Character Reader(OCR) scanners, key guards, headsticks, switches, touch screens, etc which can be used to provide access to computing capabilities. It is recommended that a person contact a state or not-for-profit organization to get started in putting together a solution geared to the individulas needs. We also have over 50 authorized Assistive Technology Resellers which provide a broad array of services and products geared specifically to the assistive market. A list of these resellers is accessible from the "Authorized Reseller" item on the Home Page.
Q. Can I get programming information for developing an application which uses DECtalk?
A. A file called COMMAND.TXT is provided with the DECtalk distribution. It includes information for embedding commands into the text file being sent to the DECtalk as well as interfacing with the DECtalk DOS driver. Others who would like more information can download the file ref_man.zip from the "Tips,Tricks and Updates page accessible from the Home page or from the DECtalk BBS, 508-467-3806.
Q. I am interested in becoming a DECtalk Assistive Technology Reseller. Who do I contact?
A. Contact Anne Simoneau, Assistive Technology Reseller channel manager for more information. Her number is 508-467-3826 and e-mail: simoneau@dectlk.enet.dec.com.
Q. How is this different from other DECtalk products?
A. The DECtalk Express is a companion product to the DECtalk PC. The DECtalk Express is a small portable external unit which connects to the serial port of a PC. It allows DECtalk speech synthesis to be used where the internal DECtalk PC2 adapter card is not appropriate. Both products address the needs of people with disabilities. The other DECtalk/DECvoice products which include telephone line interfaces are geared more to commercial applications.
Q. How good is DECtalk Express?
A. DECtalk speech synthesis is widely recognized as the most natural sounding available on the market today. It is priced at the high end of the spectrum but high quality, natural sounding speech requires significant and relatively expensive components.
Q. What applications support it?
A. The primary application areas are "screen access" for persons who are blind or visually impaired, a "learning aid" for people who have learning difficulties such as dyslexia and a "voice output communication aid" (VOCA) for people with speaking disabilities. Refer to the "Applications" item accessible from the Home page for specific applications.
Q. Do I need one of these "special" software applications to be able to use DECtalk Express?
A. No. Text files can be sent to the DECtalk Express to speak using the DOS COPY command or by using a terminal emulator software package like Kermit or the Windows Terminal program. These text files can include imbedded commands for changing the synthesizers parameters like voices and speaking rate.
Q. What is different between a DECtalk PC and a DECtalk PC2?
A. There are several differences between the DECtalk PC and the DECtalk PC2. They include size, performance, I/O address and audio outputs. The DECTalk PC2 is shorter, its on-board processor runs at a faster clock rate, the I/O address can be selected from one of 64 addressable and audio outputs are available for mono, stereo and for internal connection. The following table lists the major differences:
| DECtalk PC | DECtalk PC2 | |
| Size | 13.3" x 4.25" x 0.5" | 8.75" x 4.25" x 0.5" |
| I/O Address | 4 | 64 |
| Processor Clock | 10MHz | 20MHz |
| Audio Connectors | Mono | Mono, Stereo, Internal |
Q. What is the significance of the differences between the DECtalk PC and the DECtalk PC2?
A. 1.The shorter length of the DECtalk PC2 will allow it to be installed more readily in newer PCs that have fewer full length ISA slots. 2. The increased number of I/O addresses available will make it less likely to conflict with other devices. 3. The increased on-board processor speed should provide increased responsiveness for most applications. 4. The stereo jack allows the use of stereo computer speakers without the use of a mono-to-stereo adapter.
Q. Is there a trade-in program for DECtalk PCs for the DECtalk PC2?
A. No trade-in program is available. However, software upgrades are available which should provide similar text-to-speech capabilties over time.
Q. What is the difference between DECtalk Software and the DECtalk hardware products, such as the DECtalk PC2 or the DECtalk Express?
A. DECtalk Software is the newest member of the DECtalk family, it is a software-only solution which does not require any special hardware, only a sound card supported by the operating system and at least a 486/50 CPU. DECtalk Software provides the same functionality and high quality speech synthesis as the other DECtalk products.
Q. What operating systems does DECtalk Software support?
A. DECtalk Software runs under Intel environments running Windows NT or Windows 95, it also supports Alpha environments running Windows NT.
Q. What Screen Access programs support DECtalk Software?
A. At this point in time, although many of the assistive application developers have an evaluation copy of the DECtalk Software SDK, there are no known screen access programs supporting DECtalk Software.
Q. Where can I get a demo of DECtalk Software?
A. A demo is available on this site. Click here to download a self-extracting file reader demo.
Q. What is the Assistive Technology Value Added Reseller Program?
A. The Value Added Reseller Program is a program that allows resellers to purchase DECtalk products at a discount. A reseller can only become an Assistive Technology Reseller if they market primarily to the Assistive Market, those who are visually or vocally impaired, AND provide added value to the DECtalk products, such as bundling with a screen access program, providing customer support, installations, marketing, etc.
Q. I am interested in becoming a DECtalk Assistive Technology Reseller, who do I contact?
A. Contact Anne Simoneau, Assistive Technology Reseller channel manager for more information. Her number is 508-467-3826 and e-mail: simoneau@dectalk.mro.dec.com.
This page last updated 3/4/97.