78
Stack Score
Best for
Product teams building voice AI where emotional nuance and natural prosody matter more than raw voice variety.
At a glance
- Pricing
- freemium
- Setup time
- 1 hour
- Learning curve
- medium
- Last verified
- 5/19/2026
What we love
- ✓Best-in-class emotional nuance in voice output
- ✓Low latency suitable for natural conversation
- ✓Good developer DX with WebSocket sample apps
- ✓Strong research pedigree from Alan Cowen
Where it falls short
- −Pricing per minute adds up fast at scale
- −Smaller voice library than ElevenLabs
- −EVI works best in English — other languages are limited
Pricing
✓ Pricing verified Jun 21, 20265 tiers
Free
$0
per month
- ✓10,000 characters/month (~10 min)
- ✓5 minutes EVI usage
- ✓1 concurrent connection
- ✓Unlimited voice cloning
- ✓Discord support
Starter
$3
per month
- ✓30,000 characters/month
- ✓40 minutes EVI usage
- ✓5 concurrent connections
- ✓Commercial license
- ✓Discord support
Creator
$14
per month
- ✓140,000 characters (~140 min)
- ✓200 minutes EVI usage
- ✓75 RPM
- ✓$0.15/1,000 additional characters
- ✓Voice conversion
Pro
$70
per month
- ✓1,000,000 characters (~1,000 min)
- ✓1,200 minutes EVI usage
- ✓10 concurrent connections
- ✓$0.12/1,000 additional characters
- ✓External LLMs
Enterprise
Custom
annual contract
- ✓Unlimited characters & EVI
- ✓Custom RPM & connections
- ✓Slack support
- ✓SOC 2 Type II, GDPR, HIPAA
- ✓Unlimited team seats
Why we picked it
Different category — built for customer-support and wellness bots that need emotional awareness.
Overview
Voice + chat AI that detects emotional tone in input and responds accordingly. Empathic Voice Interface (EVI) for app integrations.
Key features
- ●Empathic Voice Interface (EVI) with prosodic emotion modeling
- ●Voice-to-voice latency under 700ms
- ●Detects 48 distinct emotional expressions in speech
- ●Custom voice creation from short audio samples
- ●WebSocket and REST APIs for real-time apps
- ●Octave TTS model with expressive long-form synthesis
- ●Compliance-friendly with audit logs and PII controls
Best use cases
Empathic AI companions
Build voice agents for coaching, therapy support, or accessibility that read user emotion and respond accordingly.
Expressive narration
Generate audiobook or podcast narration that varies prosody based on content.
Voice-first product UX
Replace chat with conversational voice in consumer apps where tone matters.
Integrations
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