Accuracy methodology (high level)

In short: Recorded fixture runs through the real pipeline; curated references gate quality; lag sampled at time checkpoints; your room still dominates.

Last updated 5 October 2026

Why this page exists

Churches ask “How accurate is it?” Marketing percentages are easy to invent and hard to trust. This page explains what we measure internally when we change speech, translation, or audio delivery—so you can align expectations with process, not slogans.

We do not treat these lab metrics as a promise for your sanctuary. Your mixer, mic technique, and network dominate Sunday outcomes.

End-to-end, not cherry-picked demos

Evaluation runs the same path listeners use:

  1. Fixture audio (sermon-style recordings) enters live speech recognition
  2. Text is translated and synthesized (including Flash or clip paths where enabled)
  3. Output audio is captured and re-transcribed to approximate what a listener heard
  4. Results are compared to curated reference transcripts for that fixture—not to whatever the model happened to print that day

That closes the loop from pulpit feed → ear, not “translation API on perfect text.”

Word error rate (WER) and coverage

For each fixture we maintain reference source and target text.

SignalMeaning (simplified)
Source WERHow close streaming STT is to the curated source transcript
Target WER / coverageHow close heard translation (via re-STT of TTS output) is to the curated target

High WER or low coverage triggers investigation in grouping, timing, and TTS continuity—common causes of “choppy” worship audio—not automatic model swaps.

We compare against expected.json-style references, not against the pipeline’s own best guess as ground truth.

Lag and continuity checkpoints

Accuracy is not only words—it is when words arrive.

Smoke and eval runs record checkpoints at fixed times into a segment (for example 10s, 30s) for:

  • How far translation text trails live speech
  • How far played audio trails live speech

Separately, continuity heuristics flag mid-sentence clip breaks and unnatural gaps between spoken chunks—failure modes that feel worse in a sermon than raw WER suggests.

See listener-facing symptoms: Captions lag, Fragmentary captions.

What we do not do

  • Publish a single “X% accurate” banner for all languages and rooms
  • Replace your pilot in the building with a lab score
  • Treat translation text in the database alone as “heard quality” when audio delivery diverges

What your church should do

Read the pastoral framing in How accurate is AI sermon translation?, then run a pre-service test and bilingual feedback loop—Pre-service test, Quick guide for speakers.

If you need deeper technical detail for partnership or research pilots, contact Sanalive through your account channel.