The Wake Word Trained on This Mac

I said “hey Hearthlen” from the next machine. The ThinkPad logged score 0.99. The sentence before it, “open the browser”, did not wake it.

Savindu Thathsara, savithathsara.me. This is a Hearthlen note from the two computers sitting together.

The earlier listener, in the name it hears, transcribed a burst and then guessed. The same phrase came back as Hertzland, Herthlin, and once as something that was not the name at all. There is no published model for this name. openWakeWord already publishes the mel network and the speech-embedding network, and those stay frozen. I trained only the small phrase head, on this Mac, from offline speech, and copied the three files to the ThinkPad. The listener scores each 80 ms of microphone audio on the laptop. It does not download a model when someone says the name.

The holdout from that training run was positives 0.96, negatives 0.04, recall 0.91, false accepts 0.00. The laptop uses threshold 0.97. The phrase finished at 10:06:48.494 and the log line is that same second, score 0.98. A later pass scored 0.99, said hello, and heard the next sentence: Turn the volume up. Speech-to-text took 367 ms. The turn took 1914 ms. With the speaker turned down to 46, the same phrase scored 0.91 and stayed quiet.

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Savindu Thathsara builds practical AI and automation in London. This series is the public log of an offline AI operating system he is writing and learning at the same time.

• Site: https://savithathsara.me
• Email: [e-mail]
• DEV: https://dev.to/savinduthathsara