Ambient volume control in open audio device

1. A method performed by a wearable audio device comprising:

outputting an audio signal having an adjusted sound pressure level (SPL) based on ambient noise in a vicinity of the wearable audio device;

further adjusting the SPL of the audio signal by:

applying a first SPL boost to the audio signal to increase the adjusted SPL of the audio signal based on the ambient noise in the vicinity increasing; or

applying a second SPL boost to the audio signal to decrease the adjusted SPL of the audio signal based on the ambient noise in the vicinity decreasing,

wherein the first and second SPL boosts are applied to both lower frequencies and higher frequencies of the audio signal, wherein the first and second SPL boosts for both the lower frequencies and the higher frequencies of the audio signal are dependent upon the ambient noise in the vicinity, wherein the dependency varies among the lower frequencies and the higher frequencies; and

outputting the audio signal having the further adjusted SPL, wherein the further adjusted SPL minimizes leakage to the outside environment.

2. The method of claim 1 , wherein:

application of the first SPL boost to the audio signal to increase the adjusted SPL of the audio signal increases the adjusted SPL of the audio signal to be greater than the SPL of the ambient noise by at least a sound pressure threshold amount; and

application of the second SPL boost to the audio signal to decrease the adjusted SPL of the audio signal decreases the adjusted SPL of the audio signal to be greater than the SPL of the ambient noise by at least the sound pressure threshold amount.

3. The method of claim 2 , wherein the first and second SPL boosts applied to both the lower frequencies and the higher frequencies of the audio signal boosts an SPL more for lower frequencies of the audio signal as compared to higher frequencies of the audio signal.

4. The method of claim 1 , wherein:

application of the first SPL boost to the audio signal to increase the adjusted SPL of the audio signal is further based on an absolute value of a difference between the adjusted SPL of the audio signal and an SPL of the ambient noise is greater than a first sound pressure threshold amount.

5. The method of claim 4 , wherein application of the first SPL boost to the audio signal to increase the adjusted SPL of the audio signal comprises:

increasing the SPL of the audio signal until the adjusted SPL of the audio signal exceeds the SPL of the ambient noise by more than a second sound pressure threshold amount, wherein the first and second sound pressure threshold amounts are different.

6. The method of claim 1 , further comprising:

detecting, by a microphone on the wearable audio device, the ambient noise, and wherein the microphone is further configured for detecting speech of a user wearing the wearable audio device.

7. The method of claim 6 , wherein the microphone is located in an acoustic null of a speaker configured to output the audio signal having the further adjusted SPL.

8. The method of claim 1 , wherein the wearable audio device comprises an off-ear headphone or audio eyeglasses.

9. The method of claim 1 , wherein the wearable audio device outputs the audio signal having the further adjusted SPL without physically obstructing a path between an ear canal of a user wearing the wearable audio device and user's ear canal and outside the user's ear canal.

10. A wearable audio device comprising:

a speaker configured to output an audio signal having an adjusted sound pressure level (SPL) based on ambient noise in a vicinity of the wearable audio device; and

a processor configured to further adjust the SPL of the audio signal by:

applying a first SPL boost to the audio signal to increase the adjusted SPL of the audio signal based on the ambient noise in the vicinity increasing; or

applying a second SPL boost to the audio signal to decrease the adjusted SPL of the audio signal based on the ambient noise in the vicinity decreasing,

wherein the first and second SPL boosts are applied to both lower frequencies and higher frequencies of the audio signal, wherein the first and second SPL boosts for both the lower frequencies and the higher frequencies of the audio signal are dependent upon the ambient noise in the vicinity, wherein the dependency varies among the lower frequencies and the higher frequencies,

wherein the speaker is further configured to output the audio signal having the further adjusted SPL, wherein the further adjusted SPL minimizes leakage to the outside environment.

11. The wearable audio device of claim 10 , wherein the speaker is configured to output the audio signal having the further adjusted SPL without physically obstructing a path between an ear canal of a user wearing the wearable audio device and user's ear canal and outside the user's ear canal.

12. The wearable audio device of claim 10 , wherein the wearable audio device further comprises:

a microphone configured to detect the ambient noise and speech of a user wearing the wearable audio device.

13. The wearable audio device of claim 12 , wherein the wearable audio device comprises audio eyeglasses, and wherein the microphone is housed in a frame configured to rest on a user.

14. The wearable audio device of claim 13 , wherein the microphone is housed proximate a temple region above an ear of a user wearing the wearable audio device.

15. The wearable audio device of claim 12 , wherein the microphone is located in an acoustic null of the speaker, such that the microphone substantially only detects the ambient noise and substantially does not detect the audio signal having the adjusted SPL.

16. The wearable audio device of claim 14 , wherein the speaker outputs the audio signal having the adjusted SPL in a first direction, and the microphone is oriented to detect sound substantially outside of the first direction.

17. The wearable audio device of claim 10 , wherein:

the processor is configured to apply the first SPL boost to the audio signal to increase the adjusted SPL of the audio signal to be greater than the SPL of the ambient noise by at least a sound pressure threshold amount; and

the processor is configured to apply the second SPL boost to the audio signal to decrease the adjusted SPL of the audio signal to be greater than the SPL of the ambient noise by at least the sound pressure threshold amount.

18. The wearable audio device of claim 10 , wherein the processor is configured to apply the first and second SPL boosts applied to both the lower frequencies and the higher frequencies of the audio signal by:

boosting an SPL more for lower frequencies of the audio signal as compared to higher frequencies of the audio signal.

19. The wearable audio device of claim 10 , wherein the processor is configured to apply the first SPL boost to the audio signal to increase the adjusted SPL of the audio signal is further based on an absolute value of a difference between the adjusted SPL of the audio signal and an SPL of the ambient noise being greater than a first sound pressure threshold amount.

20. The wearable audio device of claim 19 , wherein the processor is configured to apply the first SPL boost to the audio signal to increase the adjusted SPL of the audio signal until the adjusted SPL of the audio signal exceeds the SPL of the ambient noise by more than a second sound pressure threshold amount, wherein the first and second sound pressure threshold amounts are different.