238 ms median and 432 ms P95 time to first audio on Coval (30 days to October 22, 2026): Visible delay speed tier.
Benchmark summary: Visible delay speed tier on Coval's P95 (the voice becomes a visible part of the delay).
Deepdub Phantom Z 3.4 conversational is a proprietary text-to-speech (TTS) API from Deepdub, measured by one independent benchmark, Coval.
Speed tier
Visible delayP95 of 320 ms or more. The voice becomes a visible part of the delay.
Data read October 22, 2026. No combined score: methodology
Gradium TTS vs Deepdub Phantom Z 3.4 conversational Fastest TTS APIs, by speed tierOn Coval's 30-day window ending October 22, 2026 (3,101 runs from US East), Deepdub Phantom Z 3.4 conversational starts speaking after 238 ms on a typical turn (median) and 431.7 ms on a slow turn (P95, the slowest one in twenty). That P95 is 20th lowest of the 32 models Coval measures, which puts it in the Visible delay tier: the voice becomes a visible part of the delay.
Neither Speko nor Artificial Analysis rates its voice quality.
Speko has not scored its pronunciation of numbers and dates.
No list price is published by Coval, Speko or Artificial Analysis for this model.
Rime Coda is a proprietary text-to-speech (TTS) API from Rime, measured by three independent benchmarks: Artificial Analysis, Coval and Speko.
Out of Set Airy TTS is a proprietary text-to-speech (TTS) API from Out of Set, measured by two independent benchmarks: Coval and Speko.
Cartesia Sonic 3.5 is a proprietary text-to-speech (TTS) API from Cartesia, measured by three independent benchmarks: Artificial Analysis, Coval and Speko.