> ## Documentation Index > Fetch the complete documentation index at: https://docs.slng.ai/llms.txt > Use this file to discover all available pages before exploring further. # Gradium TTS default > Real-time multilingual text-to-speech with streaming WebSocket and one-shot HTTP synthesis ## AsyncAPI ````yaml api-reference/asyncapi/tts-gradium.asyncapi.yaml /v1/tts/gradium/tts:default id: /v1/tts/gradium/tts:default title: Gradium TTS default description: >- Real-time multilingual text-to-speech with streaming WebSocket and one-shot HTTP synthesis servers: - id: production protocol: wss host: api.slng.ai bindings: [] variables: [] - id: staging protocol: wss host: stageapi.slng.ai bindings: [] variables: [] address: /v1/tts/gradium/tts:default parameters: [] bindings: - protocol: ws version: latest value: method: GET headers: type: object properties: X-World-Part-Override: type: string description: Override target world part. Auto-selected if not provided. x-parser-schema-id: x-parser-schema-id: WebsocketHeadersGradium schemaProperties: - name: method type: string description: GET required: false - name: headers type: object required: false properties: - name: X-World-Part-Override type: string description: Override target world part. Auto-selected if not provided. required: false operations: - &ref_1 id: ttsGradiumTtsDefaultReceiveSetup title: Tts gradium tts default receive setup description: Send Setup on Gradium Gradium TTS default type: receive messages: - &ref_7 id: GradiumTtsDefaultSetup contentType: application/json payload: - name: Setup description: Initialize the synthesis stream. Must be the first message. type: object properties: - name: const type: string description: setup required: false - name: voice_id type: string required: true - name: model_name type: string required: false - name: output_format type: string enumValues: - wav - pcm - pcm_8000 - pcm_16000 - pcm_24000 - opus - ulaw_8000 - alaw_8000 required: false - name: json_config type: object required: false properties: - name: language type: string required: false - name: temperature type: number required: false - name: close_ws_on_eos type: boolean required: false headers: [] jsonPayloadSchema: type: object description: Initialize the synthesis stream. Must be the first message. required: - type - voice_id properties: type: const: setup x-parser-schema-id: voice_id: type: string x-parser-schema-id: model_name: type: string default: default x-parser-schema-id: output_format: type: string enum: - wav - pcm - pcm_8000 - pcm_16000 - pcm_24000 - opus - ulaw_8000 - alaw_8000 x-parser-schema-id: json_config: type: object properties: language: type: string x-parser-schema-id: temperature: type: number x-parser-schema-id: x-parser-schema-id: close_ws_on_eos: type: boolean x-parser-schema-id: x-parser-schema-id: title: Setup description: Initialize the synthesis stream. Must be the first message. example: |- { "type": "setup", "voice_id": "" } bindings: [] extensions: - id: x-parser-unique-object-id value: GradiumTtsDefaultSetup bindings: [] extensions: &ref_0 - id: x-parser-unique-object-id value: /v1/tts/gradium/tts:default - &ref_2 id: ttsGradiumTtsDefaultReceiveText title: Tts gradium tts default receive text description: Send Text on Gradium Gradium TTS default type: receive messages: - &ref_8 id: GradiumTtsDefaultText contentType: application/json payload: - name: Text description: A chunk of text to synthesize. type: object properties: - name: const type: string description: text required: false - name: text type: string required: true headers: [] jsonPayloadSchema: type: object description: A chunk of text to synthesize. required: - type - text properties: type: const: text x-parser-schema-id: text: type: string x-parser-schema-id: x-parser-schema-id: title: Text description: A chunk of text to synthesize. example: |- { "type": "text", "text": "Hello world." } bindings: [] extensions: - id: x-parser-unique-object-id value: GradiumTtsDefaultText bindings: [] extensions: *ref_0 - &ref_3 id: ttsGradiumTtsDefaultReceiveEndOfStream title: Tts gradium tts default receive end of stream description: Send EndOfStream on Gradium Gradium TTS default type: receive messages: - &ref_9 id: GradiumTtsDefaultEndOfStreamRequest contentType: application/json payload: - name: EndOfStream description: Signal that no more text will be sent. type: object properties: - name: const type: string description: end_of_stream required: false headers: [] jsonPayloadSchema: type: object description: Signal that no more text will be sent. required: - type properties: type: const: end_of_stream x-parser-schema-id: x-parser-schema-id: title: EndOfStream description: Signal that no more text will be sent. example: |- { "type": "end_of_stream" } bindings: [] extensions: - id: x-parser-unique-object-id value: GradiumTtsDefaultEndOfStreamRequest bindings: [] extensions: *ref_0 - &ref_4 id: ttsGradiumTtsDefaultSendAudio title: Tts gradium tts default send audio description: Receive Audio on Gradium Gradium TTS default type: send messages: - &ref_10 id: GradiumTtsDefaultAudio contentType: application/json payload: - name: Audio description: A chunk of base64-encoded synthesized audio. type: object properties: - name: const type: string description: audio required: false - name: audio type: string required: true - name: start_s type: number required: false - name: stop_s type: number required: false - name: stream_id type: integer required: false headers: [] jsonPayloadSchema: type: object description: A chunk of base64-encoded synthesized audio. required: - type - audio properties: type: const: audio x-parser-schema-id: audio: type: string format: base64 x-parser-schema-id: start_s: type: number x-parser-schema-id: stop_s: type: number x-parser-schema-id: stream_id: type: integer x-parser-schema-id: x-parser-schema-id: title: Audio description: A chunk of base64-encoded synthesized audio. example: |- { "type": "audio", "audio": "