# US 10,374,566 B2 · Perceptual power reduction system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,566 B2 - Document ID: US10374566B2 - Status: Granted - Kind: B2 - Application number: 15/661,355 - Filed: 2017-07-27 - Published: 2018-02-01 - Granted: 2019-08-06 - Earliest claimed: 2016-07-29 - Assignees: Maxim Integrated Products, Inc. - Applicants: Maxim Integrated Products, Inc. - Inventors: Vivek P. Nigam; Robert Polleros; Wen Jin - Web page: https://patentgrep.com/patent/US10374566B2 ## CPC - H03G 3/32: the control being dependent upon ambient noise level or sound level - H03G 3/3005: {in amplifiers suitable for low-frequencies, e.g. audio amplifiers (H03G3/32, H03G3/34 take precedence)} - H03G 5/005: {of digital signals} - H03G 5/165: {Equalizers; Volume or gain control in limited frequency bands} - H04R 3/04: for correcting frequency response - H04R 29/001: {for loudspeakers (H04R29/007 takes precedence)} - H04R 2420/07: Applications of wireless loudspeakers or wireless microphones - H04R 2430/03: Synergistic effects of band splitting and sub-band processing - H04R 2460/03: Aspects of the reduction of energy consumption in hearing devices - H03G: CONTROL OF AMPLIFICATION - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) ## Abstract A method of reducing power consumed by an audio playback system includes: receiving a signal from a digital audio interface; comparing a sound pressure level (SPL) response of a first frequency band of the signal to a total SPL response of the signal, the first frequency band including frequencies lower than a selected frequency; and attenuating signal components in the first frequency band of the signal based upon the comparison of the SPL response of the first frequency band of the signal to the total SPL response of the signal. ## Claims ### Claim 1 A method of reducing power consumption by an audio playback system, comprising: receiving a signal from a digital audio interface; comparing a sound pressure level (SPL) response of a first frequency band of the signal to a total SPL response of the signal, the first frequency band including frequencies lower than a selected frequency, by determining a ratio of the SPL response of the first frequency band of the signal to the total SPL response of the signal and comparing the determined ratio to a threshold ratio, wherein the selected frequency and the threshold ratio are based on a speaker SPL response; and attenuating signal components in the first frequency band of the signal based upon the comparison of the SPL response of the first frequency band of the signal to the total SPL response of the signal, when the determined ratio is less than the threshold ratio. ### Claim 2 (depends on 1) The method of claim 1, wherein determining the ratio of the SPL response of the first frequency band of the signal to the total SPL response of the signal includes: determining a root mean square value of the SPL response of the first frequency band of the signal; determining a root mean square value of the total SPL response of the signal; and determining a ratio of the root mean square value of the SPL response of the first frequency band of the signal to the root mean square value of the total SPL response of the signal. ### Claim 3 (depends on 1) The method of claim 1, wherein the signal components in the first frequency band are attenuated to zero, near zero, or completely removed when the determined ratio is lower than the threshold ratio. ### Claim 4 (depends on 1) The method of claim 1, further comprising: generating an output signal by adding the signal components in the first frequency band of the signal to signal components in a second frequency band of the signal when the determined ratio is greater than the threshold ratio, the second frequency band of the signal including frequencies greater than the selected frequency. ### Claim 5 (depends on 1) The method of claim 1, further comprising: attenuating signal components at frequencies above a second selected frequency, the second selected frequency greater than the selected frequency. ### Claim 6 An audio playback system, comprising: a digital audio interface; and a controller configured to: receive a signal from the digital audio interface; compare a sound pressure level (SPL) response of a first frequency band of the signal to a total SPL response of the signal, the first frequency band including frequencies lower than a selected frequency, by determining a ratio of the SPL response of the first frequency band of the signal to the total SPL response of the signal and comparing the determined ratio to a threshold ratio, wherein the selected frequency and the threshold ratio are based on a speaker SPL response; and attenuate signal components in the first frequency band of the signal based upon the comparison of the SPL response of the first frequency band of the signal to the total SPL response of the signal when the determined ratio is less than the threshold ratio; and an amplifier configured to receive the signal from the controller and amplify the signal. ### Claim 7 (depends on 6) The audio playback system of claim 6, wherein the controller is configured to determine the ratio of the SPL response of the first frequency band of the signal to the total SPL response of the signal by: determining a root mean square value of the SPL response of the first frequency band of the signal; determining a root mean square value of the total SPL response of the signal; and determining a ratio of the root mean square value of the SPL response of the first frequency band of the signal to the root mean square value of the total SPL response of the signal. ### Claim 8 (depends on 6) The audio playback system of claim 6, wherein the signal components in the first frequency band are attenuated to zero, near zero, or completely removed when the determined ratio is lower than the threshold ratio. ### Claim 9 (depends on 6) The audio playback system of claim 6, wherein the controller is further configured to generate an output signal by adding the signal components in the first frequency band of the signal to signal components in a second frequency band of the signal when the determined ratio is greater than the threshold ratio, the second frequency band of the signal including frequencies greater than the selected frequency. ### Claim 10 (depends on 6) The audio playback system of claim 6, wherein the controller is further configured to attenuate signal components at frequencies above a second selected frequency, the second selected frequency greater than the selected frequency. ### Claim 11 (depends on 6) The audio playback system of claim 6, wherein the amplifier at least partially includes the controller. ### Claim 12 A controller for an audio playback system, the controller comprising: a processor; a memory communicatively coupled to the processor, the memory having one or more modules stored thereon, the one or more modules, when executed by the processor, causing the processor to: receive a signal from a digital audio interface; compare a sound pressure level (SPL) response of a first frequency band of the signal to a total SPL response of the signal, the first frequency band including frequencies lower than a selected frequency, by determining a ratio of the SPL response of the first frequency band of the signal to the total SPL response of the signal and comparing the determined ratio to a threshold ratio, wherein the selected frequency and the threshold ratio are based on a speaker SPL response; and attenuate signal components in the first frequency band of the signal based upon the comparison of the SPL response of the first frequency band of the signal to the total SPL response of the signal when the determined ratio is less than the threshold ratio. ### Claim 13 (depends on 12) The controller of claim 12, wherein the one or more modules are configured to cause the processor to determine the ratio of the SPL response of the first frequency band of the signal to the total SPL response of the signal by: determining a root mean square value of the SPL response of the first frequency band of the signal; determining a root mean square value of the total SPL response of the signal; and determining a ratio of the root mean square value of the SPL response of the first frequency band of the signal to the root mean square value of the total SPL response of the signal. ### Claim 14 (depends on 12) The controller of claim 12, wherein the one or more modules are further configured to cause the processor to generate an output signal by adding the signal components in the first frequency band of the signal to signal components in a second frequency band of the signal when the determined ratio is greater than the threshold ratio, the second frequency band of the signal including frequencies greater than the selected frequency. ### Claim 15 (depends on 12) The controller of claim 12, wherein the one or more modules are further configured to cause the processor to attenuate signal components at frequencies above a second selected frequency, the second selected frequency greater than the selected frequency.