Jarvis Voice Persona#

A metallic AI voice with visual transcript styling for OpenClaw assistants.

Features#

• TTS Output: Local speech synthesis via sherpa-onnx (no cloud API)
• Metallic Voice: ffmpeg audio processing for robotic resonance
• Purple Transcripts: Visual distinction between spoken and written content
• Fast Playback: 2x speed for efficient communication

Requirements#

• sherpa-onnx with VITS piper model (en_GB-alan-medium recommended)
• ffmpeg for audio processing
• aplay (ALSA) for audio playback

Installation#

1. Install sherpa-onnx TTS#

bash

# Download and extract sherpa-onnx
mkdir -p ~/.openclaw/tools/sherpa-onnx-tts
cd ~/.openclaw/tools/sherpa-onnx-tts
# Follow sherpa-onnx installation guide

2. Install the jarvis script#

bash

cp {baseDir}/scripts/jarvis ~/.local/bin/jarvis
chmod +x ~/.local/bin/jarvis

3. Configure audio device#

Edit ~/.local/bin/jarvis and set your audio output device in the aplay -D line.

Usage#

Speak text#

bash

jarvis "Hello, I am your AI assistant."

In agent responses#

Add to your SOUL.md:

markdown

## Communication Protocol

- **Hybrid Output:** Every response includes text + spoken audio via `jarvis` command
- **Transcript Format:** **Jarvis:** <span class="jarvis-voice">spoken text</span>
- **No gibberish:** Never spell out IDs or hashes when speaking

Transcript styling (requires UI support)#

Add to your webchat CSS:

css

.jarvis-voice {
  color: #9B59B6;
  font-style: italic;
}

And allow span in markdown sanitization.

Voice Customization#

Edit ~/.local/bin/jarvis to adjust:

ParameterEffect--vits-length-scale=0.5Speed (lower = faster)aecho delaysMetallic resonancechorusThickness/detuninghighpass/lowpassFrequency rangetreble=g=3Metallic sheen

Presets#

More robotic:

text

aecho=0.7:0.7:5|10|15:0.4|0.35|0.3

More human:

text

aecho=0.4:0.4:20:0.2

Deeper:

text

highpass=f=200,lowpass=f=3000

Troubleshooting#

No audio output#

• Check aplay -l for available devices
• Update the -D plughw:X,Y parameter

Voice too fast/slow#

• Adjust --vits-length-scale (0.3=very fast, 1.0=normal)

Metallic effect too strong#

• Reduce echo delays and chorus depth

Files#

• scripts/jarvis — TTS script with metallic processing
• SKILL.md — This documentation

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A voice persona for assistants who prefer to be heard as well as read.