Our Voice Broadcast API lets you customize the way text-to-speech (TTS) reads out your message. Use the commands on this page to set voices, speech rate, voice pitch, and pauses. You can use an unlimited number of these commands within a single script.
To adjust other aspects of your call script, refer to the TextToSay Commands page.
Inserting Silence/Pauses
Cepstral Voices
This is not <break strength=’none’ /> a pause. This is a <break strength=’x-weak’ /> phrase break. This is a <break strength=’weak’ /> phrase break. This is a <break strength=’medium’ /> sentence break. This is a <break strength=’strong’ /> paragraph break. This is a <break strength=’x-strong’ /> paragraph break. This is a <break time=’3s’ /> 3 second pause. This is a <break time=’4500ms’ /> 4.5 second pause. This is a <break /> sentence break.
Amazon Polly Voices
This is a <s> sentence </s> break. This is a <p> paragraph </p> break.
Changing Voices
Our Voice Broadcast API includes dozens of voices you can use to read your script. See TextToSay Voices for a list of the voices you can choose from.
Changing to Cepstral Voices
The following syntax can be used to select Cepstral voices. This is the default voice. <voice name=”David”>This is David.</voice> This is the default voice again. <voice name=”Callie”>Callie here.</voice>
Changing to Amazon Polly or Cepstral Voices
The following syntax can be used to select any voice, regardless of provider. Hello, thank you for calling Esendex. Have a great day. ~ChangeVoiceID(38)~ Hola, gracias por llamar a Esendex. Que tengas un gran día.
Adjusting Speech Rate
Cepstral Voices
<prosody rate=’x-slow’>I am speaking at 1/2 speed.</prosody> <prosody rate=’slow’>I am speaking at 2/3 speed.</prosody> <prosody rate=’medium’>I am speaking at normal speed.</prosody> <prosody rate=’fast’>I am speaking 33% faster than normal.</prosody> <prosody rate=’x-fast’>I am speaking at double speed.</prosody> <prosody rate=’default’>I am speaking at normal speed.</prosody> <prosody rate=’.42′>I am speaking at 42% of normal speed.</prosody> <prosody rate=’2.8′>I am speaking 2.8 times normal speed.</prosody> <prosody rate=’-0.3′>I am speaking 30% more slowly.</prosody> <prosody rate=’+0.3′>I am speaking 30% more quickly.</prosody>
Amazon Polly Voices
<prosody rate=’x-slow’>I am speaking at 1/2 speed.</prosody> <prosody rate=’slow’>I am speaking at 2/3 speed.</prosody> <prosody rate=’medium’>I am speaking at normal speed.</prosody> <prosody rate=’fast’>I am speaking 33% faster than normal.</prosody> <prosody rate=’x-fast’>I am speaking at double speed.</prosody>
Adjusting Voice Pitch
Cepstral Voices
<prosody pitch=’x-low’>This is half-pitch.</prosody> <prosody pitch=’low’>This is 3/4 pitch.</prosody> <prosody pitch=’medium’>This is normal pitch.</prosody> <prosody pitch=’high’>This is twice as high.</prosody> <prosody pitch=’x-high’>This is three times as high.</prosody> <prosody pitch=’default’>This is normal pitch.</prosody> <prosody pitch=’-50%’>This is 50% lower.</prosody> <prosody pitch=’+50%’>This is 50% higher.</prosody> <prosody pitch=’-6st’>This is six semitones lower.</prosody> <prosody pitch=’+6st’>This is six semitones higher.</prosody> <prosody pitch=’-25Hz’>This has a pitch mean 25 Hertz lower.</prosody> <prosody pitch=’+25Hz’>This has a pitch mean 25 Hertz higher.</prosody> <prosody pitch=’75Hz’>This has a pitch mean of 75 Hertz.</prosody>
Amazon Polly Voices
<prosody pitch=’x-low’>This is half-pitch</prosody> <prosody pitch=’low’>This is 3/4 pitch.</prosody> <prosody pitch=’medium’>This is normal pitch.</prosody> <prosody pitch=’high’>This is twice as high.</prosody> <prosody pitch=’x-high’>This is three times as high.</prosody> <prosody pitch=’default’>This is normal pitch.</prosody>
Adjusting Output Volume
Cepstral Voices
<prosody volume=’silent’>This is silent.</prosody> <prosody volume=’x-soft’>This is 25% as loud.</prosody> <prosody volume=’soft’>This is 50% as loud.</prosody> <prosody volume=’medium’>This is the default volume.</prosody> <prosody volume=’loud’>This is 50% louder.</prosody> <prosody volume=’x-loud’>This is 100% louder.</prosody> <prosody volume=’default’>This is the default volume.</prosody> <prosody volume=’-33%’>This is 33% softer.</prosody> <prosody volume=’+33%’>This is 33% louder.</prosody> <prosody volume=’33%’>This is 33% louder.</prosody> <prosody volume=’33’>This is 33% of normal volume.</prosody>
Amazon Polly Voices
<prosody volume=’silent’>This is silent.</prosody> <prosody volume=’x-soft’>This is 25% as loud.</prosody> <prosody volume=’soft’>This is 50% as loud.</prosody> <prosody volume=’medium’>This is the default volume.</prosody> <prosody volume=’loud’>This is 50% louder.</prosody> <prosody volume=’x-loud’>This is 100% louder.</prosody> <prosody volume=’default’>This is the default volume.</prosody>
Adding Emphasis to Speech
Cepstral Voices
This is <emphasis level=’strong’>stronger</emphasis> than the rest. This is <emphasis level=’moderate’>somewhat stronger</emphasis> than the rest. This is <emphasis level=’none’>the same as</emphasis> the rest.
Amazon Polly Voices
This is <emphasis level=’strong’>stronger</emphasis> than the rest. This is <emphasis level=’moderate’>somewhat stronger</emphasis> than the rest. This is <emphasis level=’reduced’>the same as</emphasis> the rest.
Speaking Words Phonetically
Cepstral Voices
You say <phoneme ph=’t ah0 m ey1 t ow0′>tomato</phoneme>, I say <phoneme ph=’t ah0 m aa1 t ow0′>tomato</phoneme>
Say-As
Date
<say-as format=”mdy” interpret-as=”date”>10/25/2020</say-as>
Digits
<say-as type=”number:digits”>[zipcode]</say-as>