0.0.6 • Public • Published

    Jaxcore Say

    A JavaScript speech synthesis and visualization system for the web, based upon meSpeak and sam-js.

    Jaxcore Say combines both speech synthesis systems through a common API with an HTML5 canvas-based audio volume display which was partially based on volume-meter.

    Beware that web browsers are now disabling Web Audio API by default, so the first usage of Jaxcore Say must be called from a user action such as mouse click or keyboard action.

    For a version of this library which works inside NodeJS, refer to:


    CyberTyper React Component

    CyberTyper is a ReactJS component for automatically typing tech synchronized with jaxcore-say's speech synthesis

    Installation (NPM module)

    npm install jaxcore-say


    English en is the default, but see below for how other languages can be used.

    import Say from "jaxcore-say";
        'espeak': 'webworkers/espeak-en-worker.js',
        'sam': 'webworkers/sam-worker.js'
    let voice = new Say({
        profile: "Cylon",
        language: "en"
    voice.say("hello my name is Cylon").then(function() {

    Webworker Usage

    Both speech synthesizers are loaded with webworkers which drastically improve memory usage. The webworker files can be downloaded here. Or to build the worker files clone this repo and run npm run build-workers and see the dist directory.

    The worker js files must be served separately from the NPM module, and the path to the files must be set using the Say.setWorkers() method.

    SAM is English only so there is only 1 webworker file for it.

    But ESpeak has many language options. For English (US) only use this:

        'espeak': 'webworkers/espeak-en-worker.js',
        'sam': 'webworkers/sam-worker.js'

    For other languages it likely will be better to use the all file:

        'espeak': 'webworkers/espeak-all-worker.js',
        'sam': 'webworkers/sam-worker.js'

    Keep in mind, the file sizes of each worker is large. English (US) is 1.7MB, and all the languages is 2.7MB. Your webserver requires proper caching of the worker files.

    Voice Profiles

    Jaxcore Say includes the following predefined ESpeak-based voices:

    • Jack
    • Pris
    • Roy
    • Scotty
    • Xenu
    • Cylon
    • Leon
    • Rachel
    • Zhora
    • Borg (a combination of other espeak voices)

    And the following SAM-based voices:

    • Sam
    • Elf
    • Robo
    • Granny

    Custom voices can be generated at run time. See the source code of SayApp.js example for details.


    The voice profiles include an easy way to modify the speed (faster/slower) and pitch (deeper/higher):

    voice.say('hello world', {
      fast: true
    voice.say('hello world', {
      slow: true
    voice.say('hello world', {
      high: true
    voice.say('hello world', {
      low: true

    ESpeak Languages

    The language should be defined while instantiating new Say(), the possible languages are:

    • ca = Catalan
    • cs = Czech
    • de = German
    • el = Greek
    • en = English
    • en-n = English (N)
    • en-rp = English (RP)
    • en-sc = English (Scottish)
    • en-us = English (US)
    • en-wm = English (WM)
    • eo = Esperanto
    • es = Spanish
    • es-la = Spanish (Latin America)
    • fi = Finnish
    • fr = French
    • hu = Hungarian
    • it = Italian
    • kn = Kannada
    • la = Latin
    • lv = Latvian
    • nl = Dutch
    • pl = Polish
    • pt = Portuguese (Brazil)
    • pt-pt = Portuguese, European
    • ro = Romanian
    • sk = Slovak
    • sv = Swedish
    • tr = Turkish
    • zh = Chinese (Mandarin)
    • zh-yue = Chinese (Cantonese)

    Set the desired language while instantiating the Say object:

    let voice = new Say({
        profile: "Cylon",
        language: "es"
    voice.say("hola mi nombre es Cylon");

    Or switch languages at any time:


    Or set the language as a say() option:

    voice.say("bonjour je m'appelle Cylon", {
      language: "fr"

    Scope Visualization

    import {MonauralScope} from 'jaxcore-say';

    Include a canvas element somewhere in your page:

    <canvas id="scope" />

    And use the setVisualizer() method:

    var canvasElement = document.getElementById('scope');
    var monoScope = new MonauralScope(canvasElement);

    Run examples locally:

    Clone this repo, then:

    cd examples/basic-example
    npm install
    npm start

    Build all examples

    Clone this repo, then:

    npm install
    npm run build-all
    cd docs
    python -m SimpleHTTPServer
    // load http://localhost:8000

    Say Queue

    The Say Queue allows multiple Say instances (voices) to be queued up and played one by one and receive start/stop events for UI updates while that voice is speaking.

    See the multiplevoices for an example of this in action.


    Jaxcore Say is free software released under the GPL License.

    However, IANAL (I am not a lawyer) and due to the bizarre combination of dependencies and the typical use case of compilation/minification into a JavaScript file delivered over the web, the license restrictions are ambiguous.

    Original Works

    meSpeak (NPM module by Mikola Lysenko): https://github.com/mikolalysenko/mespeak

    meSpeak (emscripten port by Norbert Landsteiner): https://www.masswerk.at/mespeak/

    eSpeak http://espeak.sourceforge.net/

    SAM (reverse-engineered version of SAM by Sebastian Macke) https://github.com/s-macke/SAM

    SAM fork by Vidar Hokstad https://github.com/vidarh/SAM

    SAM-js port by Christian Schiffler https://github.com/discordier/sam

    meSpeak License

    Jaxcore Say includes modified source code from meSpeak which is GPL and also includes emscripten-compiled eSpeak code which is also GPL. Therefore this derivative work is available under the GPL.

    sam-js License

    sam-js is used as an external dependency (via NPM) for the SAM based voice profiles. sam-js was reverse engineered and could be classified as abadonware (quoted from https://github.com/s-macke/SAM) :

    The software is a reverse-engineered version of a software published more than 34 years ago by "Don't ask Software".
    The company no longer exists. Any attempt to contact the original authors failed. Hence S.A.M. can be best described as Abandonware (http://en.wikipedia.org/wiki/Abandonware)
    As long this is the case I cannot put my code under any specific open source software license. However the software might be used under the "Fair Use" act (https://en.wikipedia.org/wiki/FAIR_USE_Act) in the USA.

    Jaxcore Say will be updated according to any new information that comes to light and it is recommended that any further derivative works/improvement also be independently released under the GPL.




    npm i jaxcore-say



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