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Gradium

Gradium TTS

Measured 2026-10-01

Naturalness

1592

Win % · 95% CI

—

Drift

14

Synth p50

105ms

Measured 2026-10-01 on voice Brooklyn: three n=30 sweeps at p50 107, 103 and 105. The anchor rows matched their published cells in only 6 of 9 readings, so the formal two-sweep gate did not pass.

Robustness

0.27

Fined:

• fatal · decimals — never said “plus or minus” or “zero point zero five” (7 of 7 transcripts)

→ we sent “Tolerance is ±0.05 mm on that part.”

→ it said “Tolerance is prime oh five millimeters on that part.”

• fatal · large numbers — never said “three trillion” (48 of 49 transcripts)

→ we sent “National debt passed 3,000,000,000,000 dollars.”

→ it said “National debt passed three billion boundaries.”

• fatal · math operators — never said “divided” (7 of 7 transcripts)

→ we sent “That is 100÷4=25 per person.”

→ it said “That is 174 equals 25 per person.”

+ 25 more fined

Cost / 1M chars

$57.8

1 credit/char on the XS tier, the cheapest paid plan; $35.9 at the L tier.

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