Method and device for acute sound detection and reproduction
Earpieces and methods for acute sound detection and reproduction are provided. A method can include measuring an external ambient sound level (xASL), monitoring a change in the xASL for detecting an acute sound, estimating a proximity of the acute sound, and upon detecting the acute sound and its proximity, reproducing the acute sound within an ear canal, where the ear canal is at least partially occluded by an earpiece. Other embodiments are disclosed.
1. An earpiece configured to pass through sound from an ambient sound microphone comprising:
a housing, where the housing has a tip end and an ambient environment end;
a processor;
a first microphone configured to measure a first acoustic environment closer to the tip end than the ambient environment end, generating a first microphone signal;
a second microphone configured to measure a second acoustic environment closer to the ambient environment end than the tip end, generating a second microphone signal; and
a speaker configured to play an audio content signal, where the processor is coupled to the first microphone, the second microphone and the speaker, and where the processor is configured, if the earpiece has been placed into pass-through mode, to:
modify the first microphone signal to generate a first modified signal;
modify the second microphone signal to generate a second modified signal;
mix the first modified signal, the audio content signal and the second modified signal to generate a mixed signal; and
send the mixed signal to the speaker.
2. The earpiece according to claim 1 , where the earpiece is placed into pass-through mode when the processor detects an acute sound by examining the temporal or spectral characteristics of a portion of the second microphone signal and the examined portion exceeds a threshold value.
3. The earpiece according to claim 2 , where the first microphone is an ear canal microphone.
4. The earpiece according to claim 3 , where the second microphone is an ambient sound microphone.
5. The earpiece according to claim 4 , where the first modified signal is configured to reduce the noise in the first acoustic environment.
6. The earpiece according to claim 5 , where noise is defined as the sound in the first acoustic environment that is not a result of playing the audio content and playing the second modified signal.
7. The earpiece according to claim 6 , where the processor is configured to modify the audio content signal prior to generating the mixed signal so that the mixed signal is generated by mixing the first modified signal, the second modified signal and the modified audio content signal.
8. The earpiece according to claim 7 , further including:
a safe level check system.
9. The earpiece according to claim 8 , where the safe level check system checks if the mixed signal would exceed a safe threshold level if played by the speaker.
10. The earpiece according to claim 9 , where the safe level check system reduces the amplitude of the mixed signal if the mixed signal would exceed a safe threshold level if played by the speaker.
11. The earpiece according to claim 4 , further including
a tip, attached to the tip end of the housing.
12. The earpiece according to claim 11 , where the tip is configured to acoustically seal an ear canal when inserted therein.
13. The earpiece according to claim 12 , where the tip provides at least 10 dB acoustic isolation from 500 Hz to 4000 Hz.
14. The earpiece according to claim 7 , where a modified audio signal is a zero signal.
15. The earpiece according to claim 1 , where the earpiece has been placed into pass-through mode by a user operated mode selection.
16. The earpiece according to claim 15 , where the first microphone is an ear canal microphone.
17. The earpiece according to claim 16 , where the second microphone is an ambient sound microphone.