Speaking Rate

The default speaking rate is 180 words per minute (WPM). DECtalk Software speaking rates range from 75 to 600 WPM. In the Rate command, valid speaking rates are between 75 and 600. Rates specified outside this range are limited to the nearest legal value. Speaking rates can be adjusted to very slow, very fast, or anywhere in between by using the following commands:

[:rate 120]

Although the slowest possible rate is 75 WPM, 120 WPM is ideal for information such as phone numbers which need to be copied down by a listener. Unless the listener is actually copying down each numeral it might be frustrating to listen to extended speech at slow rates.

[:rate 160]

This rate is moderate (160 WPM). It sounds a little slow, but is sometimes preferred when DECtalk Software is speaking math equations or long lists of acronyms.

[:rate 180]

This is the default rate for DECtalk Software (180 WPM). This rate is ideal for listening to continuous text under optimal conditions.

[:rate 240]

Experienced listeners may prefer to skim material at this rate (240 WPM). Inexperienced listeners may not understand every word at this rate.

[:rate 350]

This rate (350 WPM) is too fast to follow, but can be used to quickly scan sections of text.

[:rate 550]

This rate (550 WPM) is the fastest usable rate. It is too fast for most people to follow, but can be used to scan text very quickly.

Changes in the speaking rate influence the duration and the number of pauses in text, as well as the duration of individual phonemes. At rates below 140 WPM, DECtalk Software inserts pauses at all phrase boundaries and pauses, and inserts phonemes near the ends of phrases. At rates faster than 240 WPM, DECtalk Software deletes all pauses and shortens phonemes.

Note
Near the beginning of a phrase, phonemes are fairly short at both slow and fast speaking rates.