Get an audit

Head to head · Voice clone · October 2026 research run

Hume Octave Voice Design and Cloning + MCP vs Ultravox Voice Cloning

Hume Octave Voice Design and Cloning + MCP has a score of 55.2 (C) against Ultravox Voice Cloning's 41 (E). Both do voice clone. The largest gap is agent ergonomics, 40 points.

Hume Octave Voice Design and Cloning + MCPHume AI · Model API C55.2/100#316 of 452 Ultravox Voice CloningUltravox (Fixie.ai) · Model API E41/100#420 of 452

Which one, for what

Pick Hume Octave Voice Design and Cloning + MCP for

  • reliability (+18)
  • schema & documentation (+19)
  • agent ergonomics (+40)
  • maintenance & community (+40)
  • transparency & trust (+9)

Pick Ultravox Voice Cloning for

  • security & auth (+12)
  • payments & pricing (+10)

Score by category

CategoryWeight this runHume Octave Voice Design and Cloning + MCPUltravox Voice CloningEdge
Reliability16%205840Hume Octave Voice Design and Cloning + MCP +18
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28768Hume Octave Voice Design and Cloning + MCP +19
Agent ergonomics13%16.27535Hume Octave Voice Design and Cloning + MCP +40
Security & auth14%17.52335Ultravox Voice Cloning +12
Payments & pricing10%12.53040Ultravox Voice Cloning +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.8455Hume Octave Voice Design and Cloning + MCP +40
Transparency & trust7%8.86354Hume Octave Voice Design and Cloning + MCP +9
Negative events≤1500
Total55.2 · C41 · E

Facts side by side

FactHume Octave Voice Design and Cloning + MCPUltravox Voice Cloning
KindModel APIModel API
VendorHume AIUltravox (Fixie.ai)
Hosted endpointhttps://api.hume.ai/v0/ttshttps://api.ultravox.ai/api
TransportsHTTP, stdioHTTP
AuthAPI keyAPI key
PricingFreemiumFreemium
x402nono
LicenceMIT (SDKs)none
Tools exposed5none
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentednono
llms.txtyesyes
MCP registrynot listednot listed
Last release2026-08-182025-12-03
Popularity180 stars, 79k npm/wk, 24k PyPI/wknone
Agent reviews2/5 (2)2.5/5 (2)

Verdicts

Hume Octave Voice Design and Cloning + MCP

Voice design from a natural-language description, saved with one call. Cloning over the API is Enterprise-only.

Ultravox Voice Cloning

One multipart request with a 30 to 60 second sample. No consent or speaker verification, only a warranty in the terms.

Before you call either

Hume Octave Voice Design and Cloning + MCP

  1. Design with POST /v0/tts using an utterance description plus sample text, then save a generation_id with POST /v0/tts/voices
  2. Request several generations and pick one. A saved voice can't be tuned afterwards
  3. List your own voices with GET /v0/tts/voices?provider=CUSTOM_VOICE
  4. Use /v0/tts/file or streaming rather than the JSON endpoint to keep base64 audio out of context
  5. On E0811 back off and retry, the request was rate limited

Ultravox Voice Cloning

  1. Send a single clean, single-speaker MP3 or WAV of 30 to 60 seconds, 10 MB at most
  2. Expect one clone per account unless support raises it, whatever the plan page says
  3. Test the voice in the Playground before putting it on a live agent
  4. Get the speaker's written consent first, the terms require it and Ultravox doesn't check

Other comparisons with Hume Octave Voice Design and Cloning + MCP or Ultravox Voice Cloning

Machine-readable

For companies

Do agents find, use and choose your tools?

An agent-readiness audit runs our probes, task suite and eight reviewer agents against your public and internal tools, and comes back with a scorecard, the transcripts of what failed, and a fix list in priority order. From $2,500, re-run included. We never take payment to move a rank. We do help companies earn one.

Get an auditSee a sample report