Supported Voices

Complete reference for voice settings and customization options in Synthesia videos.

📖 Official Documentation: Synthesia Supported Voices

Voice Settings Overview

Each avatar in Synthesia comes with a natural voice that can be customized using voice settings to match your content needs.

Available Parameters

interface VoiceSettings {
  speed?: number;  // Voice speed (0.5 - 2.0)
  pitch?: number;  // Voice pitch (0.5 - 2.0)
}

Speed Settings

Control how fast or slow the avatar speaks.

Speed Range and Effects

Speed	Effect	Best For
0.5	Very slow, deliberate	Complex explanations, elderly audience
0.7	Slow, clear	Educational content, non-native speakers
0.9	Slightly slow	Professional presentations
1.0	Natural pace	Default, most content
1.1	Slightly fast	Engaging content
1.3	Fast, energetic	Marketing, youth content
1.5	Very fast	Quick updates, summaries
2.0	Maximum speed	Time-compressed content

Speed Examples

// Very slow for complex topics
const slowVoice = {
  speed: 0.7,
  pitch: 1.0
};

// Natural conversational speed
const naturalVoice = {
  speed: 1.0,
  pitch: 1.0
};

// Energetic for marketing
const energeticVoice = {
  speed: 1.2,
  pitch: 1.05
};

// Fast-paced for summaries
const fastVoice = {
  speed: 1.5,
  pitch: 1.0
};

async function createWithSpeedVariations() {
  const speeds = [0.8, 1.0, 1.2, 1.4];

  const videos = await Promise.all(
    speeds.map((speed, index) =>
      synthesia.videos.createVideo({
        input: [{
          scriptText: 'This is a test of different speaking speeds. Notice how the pace affects the message delivery.',
          avatar: 'anna_costume1_cameraA',
          background: 'office',
          avatarSettings: {
            voice: 'anna_costume1_cameraA'
          }
        }],
        title: `Speed Test ${speed}x`,
        visibility: 'private',
        aspectRatio: '16:9',
        test: true
      })
    )
  );

  return videos.map(v => v.data).filter(Boolean);
}

Pitch Settings

Adjust the voice pitch to convey different emotions and tones.

Pitch Range and Effects

Pitch	Effect	Emotional Tone	Best For
0.5	Very low	Serious, authoritative	Executive announcements
0.7	Low	Professional, calm	Business presentations
0.9	Slightly low	Mature, trustworthy	Expert content
1.0	Natural	Neutral, balanced	Default content
1.05	Slightly high	Friendly, approachable	Customer service
1.1	High	Enthusiastic, engaging	Marketing content
1.3	Very high	Excited, youthful	Product launches
2.0	Maximum pitch	Extremely excited	Special announcements

Pitch Examples

// Authoritative, low pitch
const authoritativeVoice = {
  speed: 0.95,
  pitch: 0.8
};

// Friendly, higher pitch
const friendlyVoice = {
  speed: 1.0,
  pitch: 1.1
};

// Enthusiastic, high energy
const enthusiasticVoice = {
  speed: 1.2,
  pitch: 1.2
};

async function createWithPitchVariations() {
  const script = 'Welcome to our platform! We are excited to help you succeed.';

  const pitchVariations = [
    { name: 'Professional', pitch: 0.9, speed: 1.0 },
    { name: 'Friendly', pitch: 1.1, speed: 1.0 },
    { name: 'Enthusiastic', pitch: 1.2, speed: 1.1 },
    { name: 'Authoritative', pitch: 0.8, speed: 0.95 }
  ];

  const videos = await Promise.all(
    pitchVariations.map(variation =>
      synthesia.videos.createVideo({
        input: [{
          scriptText: script,
          avatar: 'anna_costume1_cameraA',
          background: 'office',
          avatarSettings: {
            voice: 'anna_costume1_cameraA'
          }
        }],
        title: `Pitch Test - ${variation.name}`,
        visibility: 'private',
        aspectRatio: '16:9',
        test: true
      })
    )
  );

  return videos.map(v => v.data).filter(Boolean);
}

Voice Combinations by Use Case

Business Communications

const businessVoiceSettings = {
  // Executive presentation
  executive: {
    speed: 0.95,
    pitch: 0.9 // Slower, authoritative
  },

  // Professional presentation
  professional: {
    speed: 1.0,
    pitch: 1.0 // Natural, clear
  },

  // Team update
  teamUpdate: {
    speed: 1.05,
    pitch: 1.0 // Slightly faster, engaging
  },

  // Customer announcement
  customerAnnouncement: {
    speed: 1.0,
    pitch: 1.05 // Warm, approachable
  }
};

async function createBusinessVideo(type: keyof typeof businessVoiceSettings) {
  const voiceSettings = businessVoiceSettings[type];

  const response = await synthesia.videos.createVideo({
    input: [{
      scriptText: 'This is a business communication with optimized voice settings.',
      avatar: 'james_costume1_cameraA',
      background: 'office',
      avatarSettings: {
        voice: 'james_costume1_cameraA'
      }
    }],
    title: `Business Video - ${type}`,
    visibility: 'private',
    aspectRatio: '16:9',
    test: true
  });

  return response.data;
}

Educational Content

const educationalVoiceSettings = {
  // Complex explanation
  complex: {
    speed: 0.8,
    pitch: 1.0 // Slower for comprehension
  },

  // Tutorial
  tutorial: {
    speed: 0.9,
    pitch: 1.05 // Clear and friendly
  },

  // Quick tip
  quickTip: {
    speed: 1.1,
    pitch: 1.1 // Faster, energetic
  },

  // Children's content
  children: {
    speed: 0.9,
    pitch: 1.2 // Slower, higher pitch
  }
};

Marketing Content

const marketingVoiceSettings = {
  // Product launch
  productLaunch: {
    speed: 1.2,
    pitch: 1.15 // Fast, exciting
  },

  // Brand story
  brandStory: {
    speed: 1.0,
    pitch: 1.05 // Natural, warm
  },

  // Call to action
  callToAction: {
    speed: 1.3,
    pitch: 1.1 // Urgent, compelling
  },

  // Testimonial
  testimonial: {
    speed: 1.0,
    pitch: 1.0 // Authentic, natural
  }
};

Avatar-Specific Voice Optimization

Recommended Settings by Avatar

const avatarVoiceOptimization = {
  // Professional female avatars
  'anna_costume1_cameraA': {
    business: { speed: 1.0, pitch: 1.0 },
    friendly: { speed: 1.05, pitch: 1.1 },
    authoritative: { speed: 0.95, pitch: 0.95 }
  },

  // Professional male avatars
  'james_costume1_cameraA': {
    business: { speed: 0.95, pitch: 0.9 },
    friendly: { speed: 1.0, pitch: 1.0 },
    authoritative: { speed: 0.9, pitch: 0.85 }
  },

  // Casual female avatars
  'sophia_costume2_cameraA': {
    tutorial: { speed: 1.0, pitch: 1.1 },
    energetic: { speed: 1.2, pitch: 1.2 },
    explanatory: { speed: 0.9, pitch: 1.05 }
  },

  // Technical avatars
  'alex_costume1_cameraA': {
    technical: { speed: 0.95, pitch: 1.0 },
    presentation: { speed: 1.0, pitch: 0.95 },
    training: { speed: 0.9, pitch: 1.0 }
  }
};

function getOptimalVoiceSettings(avatar: string, contentType: string) {
  const avatarSettings = avatarVoiceOptimization[avatar];
  if (avatarSettings && avatarSettings[contentType]) {
    return avatarSettings[contentType];
  }

  // Default fallback
  return { speed: 1.0, pitch: 1.0 };
}

Advanced Voice Techniques

Emotional Emphasis

async function createEmotionalContent() {
  const scenarios = [
    {
      emotion: 'excitement',
      script: 'We are thrilled to announce our new product launch!',
      voice: { speed: 1.3, pitch: 1.2 }
    },
    {
      emotion: 'concern',
      script: 'We need to address this issue immediately.',
      voice: { speed: 0.9, pitch: 0.9 }
    },
    {
      emotion: 'confidence',
      script: 'Our solution will deliver exceptional results.',
      voice: { speed: 1.0, pitch: 0.95 }
    },
    {
      emotion: 'warmth',
      script: 'Thank you for being part of our community.',
      voice: { speed: 1.05, pitch: 1.1 }
    }
  ];

  const videos = await Promise.all(
    scenarios.map(scenario =>
      synthesia.videos.createVideo({
        input: [{
          scriptText: scenario.script,
          avatar: 'anna_costume1_cameraA',
          background: 'office',
          avatarSettings: {
            voice: 'anna_costume1_cameraA'
          }
        }],
        title: `Emotional Voice - ${scenario.emotion}`,
        visibility: 'private',
        aspectRatio: '16:9',
        test: true
      })
    )
  );

  return videos.map(v => v.data).filter(Boolean);
}

Progressive Voice Changes

async function createProgressiveVoiceVideo() {
  const response = await synthesia.videos.createVideo({
    input: [
      {
        scriptText: 'Let me start with a calm, professional introduction.',
        avatar: 'anna_costume1_cameraA',
        background: 'office',
        avatarSettings: {
          voice: 'anna_costume1_cameraA'
        }
      },
      {
        scriptText: 'Now I will speak with more energy and enthusiasm!',
        avatar: 'anna_costume1_cameraA',
        background: 'office',
        avatarSettings: {
          voice: 'anna_costume1_cameraA'
        }
      }
    ],
    title: 'Progressive Voice Changes',
    visibility: 'private',
    aspectRatio: '16:9',
        background: 'office',
        script: 'Now I will speak with more energy and enthusiasm!',
        voiceSettings: { speed: 1.1, pitch: 1.1 }
      },
      {
        avatar: 'anna_costume1_cameraA',
        background: 'office',
        script: 'And finally, let me return to a measured, thoughtful pace.',
        voiceSettings: { speed: 0.9, pitch: 0.95 }
      }
    ],
    test: true
  });

  return response.data;
}

Language and Accent Considerations

Optimizing for Non-Native Speakers

const nonNativeOptimizations = {
  // Slower pace for better comprehension
  learners: {
    speed: 0.8,
    pitch: 1.0
  },

  // Clear pronunciation emphasis
  technical: {
    speed: 0.85,
    pitch: 1.0
  },

  // Conversational for practice
  conversational: {
    speed: 0.9,
    pitch: 1.05
  }
};

async function createForNonNativeSpeakers(script: string, level: 'beginner' | 'intermediate' | 'advanced') {
  const voiceSettings = {
    beginner: { speed: 0.7, pitch: 1.0 },
    intermediate: { speed: 0.85, pitch: 1.0 },
    advanced: { speed: 0.95, pitch: 1.0 }
  };

  const response = await synthesia.videos.createVideo({
    input: [{
      scriptText: script,
      avatar: 'anna_costume1_cameraA', // Use available avatar
      background: 'library',
      avatarSettings: {
        voice: 'anna_costume1_cameraA'
      }
    }],
    title: `Language Learning - ${level}`,
    visibility: 'private',
    aspectRatio: '16:9',
    test: true
  });

  return response.data;
}

Voice Testing and A/B Testing

Systematic Voice Testing

async function voiceABTest(script: string, title: string) {
  const voiceVariants = [
    { name: 'Natural', settings: { speed: 1.0, pitch: 1.0 } },
    { name: 'Professional', settings: { speed: 0.95, pitch: 0.95 } },
    { name: 'Energetic', settings: { speed: 1.1, pitch: 1.1 } },
    { name: 'Authoritative', settings: { speed: 0.9, pitch: 0.85 } },
    { name: 'Friendly', settings: { speed: 1.05, pitch: 1.1 } }
  ];

  const testResults = await Promise.all(
    voiceVariants.map(async (variant, index) => {
      const response = await synthesia.videos.createVideo({
        input: [{
          scriptText: script,
          avatar: 'anna_costume1_cameraA',
          background: 'office',
          avatarSettings: {
            voice: 'anna_costume1_cameraA'
          }
        }],
        title: `${title} - Voice Test ${variant.name}`,
        visibility: 'private',
        aspectRatio: '16:9',
        test: true
      });

      return {
        variant: variant.name,
        settings: variant.settings,
        videoId: response.data?.id,
        success: !!response.data
      };
    })
  );

  return testResults;
}

Voice Performance Analytics

class VoiceAnalytics {
  private performances: Array<{
    avatar: string;
    voiceSettings: any;
    contentType: string;
    rating: number;
    feedback: string;
  }> = [];

  recordPerformance(
    avatar: string,
    voiceSettings: any,
    contentType: string,
    rating: number,
    feedback: string = ''
  ) {
    this.performances.push({
      avatar,
      voiceSettings,
      contentType,
      rating,
      feedback
    });
  }

  getBestSettingsFor(avatar: string, contentType: string) {
    const matches = this.performances.filter(
      p => p.avatar === avatar && p.contentType === contentType
    );

    if (matches.length === 0) {
      return { speed: 1.0, pitch: 1.0 }; // Default
    }

    // Return settings with highest rating
    const best = matches.reduce((prev, current) =>
      prev.rating > current.rating ? prev : current
    );

    return best.voiceSettings;
  }

  getAnalytics() {
    const avgRating = this.performances.reduce((sum, p) => sum + p.rating, 0) / this.performances.length;

    const byContentType = this.performances.reduce((acc, p) => {
      if (!acc[p.contentType]) {
        acc[p.contentType] = [];
      }
      acc[p.contentType].push(p.rating);
      return acc;
    }, {} as Record<string, number[]>);

    return {
      totalTests: this.performances.length,
      averageRating: avgRating,
      contentTypePerformance: Object.entries(byContentType).map(([type, ratings]) => ({
        contentType: type,
        averageRating: ratings.reduce((sum, r) => sum + r, 0) / ratings.length,
        testCount: ratings.length
      }))
    };
  }
}

// Usage
const voiceAnalytics = new VoiceAnalytics();

// Record test results
voiceAnalytics.recordPerformance(
  'anna_costume1_cameraA',
  { speed: 1.1, pitch: 1.05 },
  'marketing',
  4.5,
  'Great energy and enthusiasm'
);

// Get best settings for future videos
const bestSettings = voiceAnalytics.getBestSettingsFor('anna_costume1_cameraA', 'marketing');

Best Practices

1. Match Voice to Content

const contentVoiceMapping = {
  // Formal content
  announcement: { speed: 0.95, pitch: 0.95 },
  policy: { speed: 0.9, pitch: 0.9 },
  legal: { speed: 0.85, pitch: 0.9 },

  // Educational content
  tutorial: { speed: 0.9, pitch: 1.05 },
  explanation: { speed: 0.85, pitch: 1.0 },
  training: { speed: 0.9, pitch: 1.0 },

  // Marketing content
  promotion: { speed: 1.2, pitch: 1.1 },
  product: { speed: 1.1, pitch: 1.05 },
  brand: { speed: 1.0, pitch: 1.05 },

  // Customer service
  support: { speed: 1.0, pitch: 1.1 },
  faq: { speed: 0.95, pitch: 1.05 },
  welcome: { speed: 1.05, pitch: 1.1 }
};

2. Consider Your Audience

const audienceVoiceSettings = {
  executives: { speed: 0.95, pitch: 0.9 },   // Authoritative, measured
  employees: { speed: 1.0, pitch: 1.0 },     // Natural, clear
  customers: { speed: 1.05, pitch: 1.1 },    // Friendly, approachable
  students: { speed: 0.9, pitch: 1.05 },     // Clear, patient
  children: { speed: 0.85, pitch: 1.2 },     // Slow, high energy
  elderly: { speed: 0.8, pitch: 1.0 }        // Very clear, patient
};

3. Test and Iterate

async function optimizeVoiceSettings(script: string, avatar: string) {
  const testSettings = [
    { speed: 0.9, pitch: 1.0 },
    { speed: 1.0, pitch: 1.0 },
    { speed: 1.1, pitch: 1.0 },
    { speed: 1.0, pitch: 0.9 },
    { speed: 1.0, pitch: 1.1 }
  ];

  const results = [];

  for (const settings of testSettings) {
    const response = await synthesia.videos.createVideo({
      input: [{
        scriptText: script,
        avatar: avatar,
        background: 'office',
        avatarSettings: {
          voice: avatar
        }
      }],
      title: `Voice Test - Speed: ${settings.speed}, Pitch: ${settings.pitch}`,
      visibility: 'private',
      aspectRatio: '16:9',
      test: true
    });

    if (response.data) {
      results.push({
        settings,
        videoId: response.data.id
      });
    }

    // Rate limiting - wait between tests
    await new Promise(resolve => setTimeout(resolve, 2000));
  }

  return results;
}

Troubleshooting Voice Issues

Common Problems and Solutions

Voice Sounds Unnatural

// Avoid extreme settings
const badSettings = { speed: 2.0, pitch: 2.0 }; // Too extreme
const goodSettings = { speed: 1.1, pitch: 1.05 }; // Subtle adjustment

Difficult to Understand

// Slow down for clarity
const claritySettings = { speed: 0.9, pitch: 1.0 };

Lacks Emotion

// Adjust pitch for emotion
const emotionalSettings = { speed: 1.05, pitch: 1.1 };

Voice Settings Validation

function validateVoiceSettings(settings: { speed?: number; pitch?: number }) {
  const errors = [];

  if (settings.speed !== undefined) {
    if (settings.speed < 0.5 || settings.speed > 2.0) {
      errors.push('Speed must be between 0.5 and 2.0');
    }
  }

  if (settings.pitch !== undefined) {
    if (settings.pitch < 0.5 || settings.pitch > 2.0) {
      errors.push('Pitch must be between 0.5 and 2.0');
    }
  }

  return {
    isValid: errors.length === 0,
    errors
  };
}

// Usage
const validation = validateVoiceSettings({ speed: 1.5, pitch: 1.2 });
if (!validation.isValid) {
  console.error('Invalid voice settings:', validation.errors);
}