@kuralle-syrinx/openai-tts

OpenAI-compatible streaming TTS plugin for Syrinx.

Supports any provider that implements the OpenAI POST /audio/speech endpoint with stream: true and returns raw mono s16le PCM. Configurable base_url, api_key, model, voice, response_format, source_sample_rate_hz, sample_rate, tempo, and extra_body.

Includes a built-in WSOLA time-stretcher for pitch-preserving tempo control (e.g. tempo: 0.9 to slow speech by 10%).

Usage

OpenAI (default)

import { OpenAICompatibleTTSPlugin } from "@kuralle-syrinx/openai-tts";

const plugin = new OpenAICompatibleTTSPlugin();
session.registerPlugin("tts", plugin);

Configuration:

{
  api_key: "sk-...",                // or set OPENAI_API_KEY env
  model: "gpt-4o-mini-tts",         // default
  voice: "alloy",
  response_format: "pcm",           // default
  sample_rate: 16000,               // engine rate; default 16000
  tempo: 1.0,                       // WSOLA stretch; default 1.0
}

Zeta (internal Sinhala TTS)

Zeta is used purely via config — no special factory or import.

import { OpenAICompatibleTTSPlugin } from "@kuralle-syrinx/openai-tts";

const plugin = new OpenAICompatibleTTSPlugin();
session.registerPlugin("zeta", plugin);

Configuration:

{
  base_url: "https://asyncdotengineering--zeta-tts-api-zetattsapi.us-east.modal.direct/v1",
  api_key: "",                      // Zeta is unauthenticated
  model: "zeta",
  source_sample_rate_hz: 48000,     // Zeta outputs 48 kHz PCM
  sample_rate: 24000,               // engine rate
  tempo: 0.9,                       // 10% slower — Zeta prosody rushes
  extra_body: {
    task_type: "Base",
    num_steps: 8,
  },
}

Config reference

| Key | Type | Default | Description | |---|---|---|---| | base_url | string | https://api.openai.com/v1 | Provider base URL (must include /v1). Falls back to OPENAI_BASE_URL env. | | api_key | string | — | Bearer token. Falls back to OPENAI_API_KEY env. | | model | string | gpt-4o-mini-tts | TTS model name. | | voice | string | — | Voice identifier. Included in the request body only when set. | | response_format | string | pcm | Audio format. | | source_sample_rate_hz | number | 24000 | Provider's output PCM sample rate. | | sample_rate | number | 16000 | Engine sample rate to resample to. | | tempo | number | 1.0 | WSOLA time-stretch factor (0.5–1.5). | | extra_body | object | — | Merged into the request JSON body last (overrides defaults). |