Speechify | SignalWire

Speechify is a text-to-speech engine offering natural voices built on its Simba model family.

Models

SignalWire supports the following Speechify models. See Speechify’s documentation for more detail.

Model	Description
`simba-3.0`	Default. Current-generation multilingual model
`simba-3.2`	English-only model with the lowest latency
`simba-english`	Legacy English model
`simba-multilingual`	Legacy multilingual model

Model availability varies per voice and per workspace — an unavailable voice and model pairing fails. Test your combination before deploying.

Voices

Press play to audition any Speechify voice, then copy config to grab the value for SWML or your SDK.

Speechify voice IDs come from its voice list API (for example, alicia or alton) — use the voice’s ID, not its display name. The default voice is alicia, an American English female voice.

Browse the available voices in Speechify’s documentation:

Speechify TTS docs

Reference for voices, models, and languages.

Speechify API console

Preview voices and manage your Speechify workspace.

Languages

Set the language as an ISO 639-1 code with a region, such as en-US. The simba-3.0 model is multilingual — it covers English, German, Spanish, French, Italian, Brazilian Portuguese, and more, and infers the language from your text in multilingual mode. Refer to Speechify’s docs for current language coverage.

Usage

A voice identifier string has three parts: the speechify engine code, a voice ID, and an optional model.

Format: speechify.<voiceId>:<model>

voiceId (required): a Speechify voice ID (for example, alicia); see Voices.
model (optional): one of the models above. Defaults to simba-3.0.

Examples:

speechify.alicia:simba-3.0
speechify.alicia

You can also set the model with the separate model parameter of the languages SWML method instead of appending :model to the voice string:

1 languages:
2 - name: English
3   code: en-US
4   voice: speechify.alicia
5   model: simba-3.0

Build with Speechify on SignalWire

Create a Space and add credit

If you don’t have one yet, you’ll need to create a SignalWire Space. Be sure to add some credit to test with.

Add a new Resource

Navigate to the Resources tab in your SignalWire Dashboard and click + Add New to create a new Resource.

Create a SWML Script

From the Resources menu, select SWML Script. Name it something fun and recognizable. Ours is titled Speechify Wizard.

Next, paste the following starter script into the text box, and hit Save:

1 version: 1.0.0
2 sections:
3   main:
4   - ai:
5       prompt:
6         text: |
7           You're Alicia, a voice from Speechify's TTS engine!
8           Introduce yourself, and have a conversation about programmable unified communications on the SignalWire platform.
9       languages:
10       - name: English
11         code: en-US
12         voice: speechify.alicia:simba-3.0

Buy and assign a phone number

Navigate to the Phone Numbers section of the Dashboard’s left sidebar menu.

Purchase a phone number and assign it to the desired SWML script.

A purchased phone number showing assignment to a specified Resource. — Assigning a phone number to the SWML Script

Give it a call!

Call the number you just assigned to chat with your new AI voice application on the phone.

Next steps with SWML

Now you’ve deployed your very first SignalWire voice AI application using Speechify voices. Next, dive deeper into SWML to explore its capabilities!

Methods reference

Documentation for all SWML methods

AI in SWML

Build advanced AI applications using SignalWire Markup Language

Guides

SWML guides and demo applications