# US 11,310,586 B2 · Nonlinear port parameters for vented box modeling of loudspeakers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,310,586 B2 - Document ID: US11310586B2 - Status: Granted - Kind: B2 - Application number: 16/160,678 - Filed: 2018-10-15 - Published: 2020-04-16 - Granted: 2022-04-19 - Earliest claimed: 2018-10-15 - Assignees: Harman International Industries, Incorporated - Applicants: Harman International Industries, Incorporated - Inventors: Russell H. Lambert; Douglas J. Button - Web page: https://patentgrep.com/patent/US11310586B2 ## CPC - H04R 1/2823: {Vents, i.e. ports, e.g. shape thereof or tuning thereof with damping material} - H04R 3/02: for preventing acoustic reaction {, i.e. acoustic oscillatory feedback (specially adapted for hearing aids H04R25/453)} - H04R 1/025: {Arrangements for fixing loudspeaker transducers, e.g. in a box, furniture} - H04R 3/007: {Protection circuits for transducers} - H04R 7/04: Plane diaphragms - H04R 9/025: {Magnetic circuit} - 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 loudspeaker parameter system for vented box driver excursion modeling, may include a loudspeaker driver having a conductor, a magnet and a diaphragm. The system may further include a processor for excursion modeling configured to receive an input signal, determine a voltage level of the input signal, an enclosure having a resonant port, estimate port parameters including at least one of an acoustic resistance or acoustic mass, and apply a voltage limit based on the vented box excursion model utilizing the port parameters. ## Claims ### Claim 1 A loudspeaker parameter system for vented box excursion modeling, comprising: a loudspeaker driver having a conductor, a magnet and a diaphragm; a processor for excursion modeling configured to: receive an input signal, determine a voltage level of the input signal based on an envelope detector, an enclosure having a resonant port, estimate port parameters including at least one of an acoustic resistance or acoustic mass, and apply a voltage limit based on the vented box excursion model utilizing the port parameters. ### Claim 2 (depends on 1) The system of claim 1, wherein the port parameters are estimated at a specific voltage level. ### Claim 3 (depends on 1) The system of claim 1, wherein the port parameters are estimated using a look-up table. ### Claim 4 (depends on 1) The system of claim 1, wherein the port parameters are estimated by curve fitting the peak input voltage level of the input signal. ### Claim 5 (depends on 1) The system of claim 1, wherein conductor is a voice coil having a voice coil excursion, and further wherein the processor is further configured to apply a lumped element model to the input signal to determine the state of the port parameters and the voice coil excursion, wherein the voltage limit is based at least in part on the voice coil excursion. ### Claim 6 (depends on 5) The system of claim 5, wherein the lumped element model is based on a DC resistance received from a thermal model. ### Claim 7 A method for modeling parameters of a vented box loudspeaker, comprising: receiving an input signal, determining a voltage level of the input signal, interpolating port parameters including at least one of an acoustic resistance and acoustic mass, and applying a voltage limit based on the port parameters. ### Claim 8 (depends on 7) The method of claim 7, wherein the voltage level is determined by an envelope detector. ### Claim 9 (depends on 7) The method of claim 7, wherein the port parameters are estimated at a specific voltage level and are voltage dependent. ### Claim 10 (depends on 9) The method of claim 9, wherein the port parameters are estimated by curve fitting the peak input voltage level of the input signal. ### Claim 11 (depends on 9) The method of claim 9, further comprising applying a lumped element model to the input signal to determine parameters and a voice coil excursion, wherein the voltage limit is based at least in part on the voice coil excursion. ### Claim 12 (depends on 11) The method of claim 11, wherein the lumped element model is based on a DC resistance received from a thermal model. ### Claim 13 (depends on 9) The method of claim 9, determining a driver resistance and delta temperature based on at least one of the voltage and current of the input signal. ### Claim 14 (depends on 7) The method of claim 7, wherein the port parameters are estimated using a look-up table. ### Claim 15 A loudspeaker parameter system, comprising: a loudspeaker having a transducer and a diaphragm; a processor for excursion modeling configured to: receive an input signal, determine the voltage level of the input signal, interpolate port parameters including an acoustic resistance and acoustic mass, and apply a voltage limit to limit excursion based on the port parameters. ### Claim 16 (depends on 15) The system of claim 15, wherein the voltage level is determined by an envelope detector. ### Claim 17 (depends on 15) The system of claim 15, wherein the acoustic resistance and acoustic mass are estimated at a specific voltage level. ### Claim 18 A loudspeaker parameter system for vented box driver excursion modeling, comprising: a loudspeaker driver having a coil, a magnet and a diaphragm; a processor for excursion modeling configured to: receive an input signal, determine a voltage input of the input signal, estimate port parameters including an acoustic resistance and acoustic mass based on a look-up table, and apply a voltage limit based on the vented box excursion model utilizing the nonlinear port parameters.