Lingua ID

The interpreter desk uses three independent hearing protection mechanisms that work together to protect the interpreter from both sudden loud peaks and prolonged exposure to high audio levels.

1. Ceiling limiter — instantaneous peak protection
   If the audio in the interpreter’s headphones would exceed 100 dB SPL at any instant, the desk limits it immediately. No warning tone is produced, the signal level is limited. This protects against very short, very loud transients such as feedback, microphone bumps, or shouts.
2. Maximum output level — short-term sustained-level protection
   If the audio level exceeds 94 dB SPL for longer than approximately 100 ms, the desk limits the output to that threshold. This catches sustained loud signals that are too long to be a harmless transient but too short to trigger the warning beep. No warning tone is produced.
3. Warning — long-term exposure protection
   The desk continuously measures the average audio level in the headphones over a sliding window of 1 minute.
   If that 1-minute average exceeds 80 dB SPL, the interpreter hears a warning consisting of 2 short beeps, each 100 ms long, separated by a 100 ms pause. The normal audio continues uninterrupted during the beeps. The beep volume adapts to the interpreter’s current listening level, scaled by the volume knob, up to a maximum of 70 dB SPL. If the volume knob is set to zero, no beeps are produced.
   After a warning, a 30-minute back-off prevents repeated alerts even if the level remains high.

Why three different thresholds?

• 100 dB SPL (ceiling limiter) protects against acute damage from very short, very loud peaks — it acts instantly.
• 94 dB SPL (maximum output level) protects against intermediate-duration loud signals (within 100 milliseconds).
• 80 dB SPL (warning beeps) protects against cumulative damage from prolonged exposure, alerting the interpreter to lower the volume before long-term hearing damage occurs.

Only the warning-beep stage produces an audible notification. The ceiling and burst limiters operate silently and automatically; the interpreter may perceive their action as a sudden reduction of the loudest peaks.

Reference table:

Please note the following about Lingua ID / Lingua ID-MM’ screen behavior:

• The screen doesn’t dim.
• The screen goes to sleep after 1 hours of inactivity.
• The screen cannot be controlled through API.
• Conditions for resetting the screen saver: pressing a physical button, audio detected in the same booth (on the A-channel)