flux

Naturalness

~1550

Win % · 95% CI

—

Drift

—

Synth p50

106ms

106–148 p50–p90

Mean of two 2026-08-12 sweeps (104/108 p50), n=30 each, concurrency 1, one keep-alive connection, 0 rejected. Anchors in the same sweeps came in 11–26% off their published cells, so the column needs a full re-baseline before these are read against each other.

Robustness

0.70

Fined: serious x1.0 never speaks a month on a US numeric date (3/4, n=1 — unconfirmed). Basis "us-only": fewer fixtures ran, so this score is optimistic against full-basis rows.

Cost / 1M chars

$45.0

Deepgram published list, Pay As You Go: $0.0450 per 1,000 characters = $45/1M. Same unit that puts Aura-2 at $0.030/1k = the $30 cell above, so the two are directly comparable — Flux TTS costs 50% more than Aura-2. Growth tier is $0.0405/1k ($40.5/1M). Free to build against through 2026-09-12 (45 concurrent streams globally, 5 EU/AU); billing starts 09-13.