# US 9,038,440 B2 · Speaker leak test 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 9,038,440 B2 - Document ID: US9038440B2 - Status: Granted - Kind: B2 - Application number: 13/461,639 - Filed: 2012-05-01 - Published: 2013-11-07 - Granted: 2015-05-26 - Earliest claimed: 2012-05-01 - Assignees: Audyssey Laboratories, Inc. - Applicants: Tyson Osborne Yaberg - Inventors: Tyson Osborne Yaberg - Web page: https://patentgrep.com/patent/US9038440B2 ## CPC - G01M 3/34: by testing the possibility of maintaining the vacuum in containers, e.g. in can-testing machines - H04R 29/001: {for loudspeakers (H04R29/007 takes precedence)} - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - 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 speaker leak test system which quickly tests if a speaker enclosure is sealed properly. The speaker leak test system tests for air leaks in the speaker enclosure, which air leaks degrade the acoustic performance of the speaker. A vacuum (or pressure) source is connected through a vacuum hose to the speaker enclosure and vacuum is drawn. After a test vacuum level is reached, the mass air flow through the vacuum hose is measured. If the mass air flow does not exceed a pre-determined speaker dependent threshold for the speaker under test, the speaker is declared to be leak free. A bypass solenoid may reside in parallel with a mass air flow sensor to reach test vacuum quickly. This speaker leak test system is intended to be used in a prototyping and production environment and tests the speaker enclosure for leaks both quickly (e.g., less than five seconds) and accurately. ## Claims ### Claim 1 A method for measuring speaker enclosure leakage, the method comprising: positioning a speaker opening of a speaker enclosure against a mating plate; assembling a mass flow sensor and air flow regulator serially in fluid communication between the mating plate and an air flow source; applying a regulated air flow by the air flow source through the mass flow sensor and the air flow regulator to the speaker enclosure under test; regulating the air flow to obtain a test pressure level in the speaker enclosure; measuring the pressure level in the speaker enclosure to obtain a measured pressure level; waiting for the measured pressure level to reach the test pressure level; measuring the mass air flow between the speaker enclosure and the air flow source by the mass flow sensor while maintaining the test pressure level; comparing the mass air flow to a threshold; and if the mass air flow does not exceed a threshold, declaring the speaker enclosure to be leak free. ### Claim 2 (depends on 1) The method of claim 1, wherein waiting for the pressure level to reach a test pressure level comprises waiting for the pressure level to reach the test pressure level of twice an extreme pressure level experienced under extreme operating conditions. ### Claim 3 (depends on 2) The method of claim 2, wherein the test pressure level is a negative gauge pressure level. ### Claim 4 (depends on 2) The method of claim 2, wherein the test pressure level is a positive gauge pressure level. ### Claim 5 (depends on 2) The method of claim 2, wherein the test pressure level is twice a pressure level experienced under extreme operating conditions. ### Claim 6 (depends on 1) The method of claim 1, wherein waiting for the pressure level to reach a test pressure level comprises waiting for the pressure level to reach a test vacuum level of about −1.5 PSIG. ### Claim 7 (depends on 1) The method of claim 1, wherein comparing the mass air flow to a threshold comprises comparing the mass air flow to a threshold of at least 0.05 Standard Fluid Liters Per Minute (SFLPM). ### Claim 8 (depends on 1) The method of claim 1, wherein comparing the mass air flow to a threshold comprises comparing the mass air flow to a threshold selected based on observed measurement of a mass air flow sensor and acoustically verifying that speaker enclosures below the threshold do not produce audible distortions caused by air leaks. ### Claim 9 (depends on 1) The method of claim 1, wherein positioning a speaker opening of a speaker enclosure under test against a vacuum plate comprises positioning a vacuum surface of the vacuum plate facing down against the speaker opening facing up. ### Claim 10 (depends on 9) The method of claim 9 wherein the vacuum surface comprises a foam rubber material. ### Claim 11 (depends on 9) The method of claim 9 wherein the vacuum surface comprising a highly compliant gap filling closed cell material. ### Claim 12 (depends on 1) The method of claim 1, further including: opening a bypass solenoid residing in parallel with a mass flow sensor measuring the mass air flow between the speaker enclosure and the air flow source, before applying a regulated vacuum; and closing the bypass solenoid after the measured pressure level approaches a test vacuum level, and before measuring the mass air flow from the speaker enclosure while maintaining the test vacuum level. ### Claim 13 (depends on 1) The method of claim 1, wherein positioning a speaker opening of a speaker enclosure against a mating plate comprises positioning the speaker opening of the speaker enclosure, absent a speaker, against a mating plate. ### Claim 14 (depends on 1) The method of claim 1, further including: opening a bypass solenoid residing in parallel with a mass flow sensor measuring the mass air flow between the speaker enclosure and the air flow source, before applying the regulated air flow; and closing the bypass solenoid after the measured pressure level approaches a test pressure level, and before measuring the mass air flow from the speaker enclosure while maintaining the test vacuum level. ### Claim 15 (depends on 1) The method of claim 1, wherein regulating the air flow to obtain a test pressure level in the speaker enclosure comprises adjusting the air flow regulator to control the regulated air flow to obtain a test pressure level in the speaker enclosure. ### Claim 16 A method for measuring speaker enclosure leakage, the method comprising: positioning a speaker opening of a speaker enclosure against a mating plate; assembling a mass flow sensor and air flow regulator serially in fluid communication between the mating plate and an air flow source; applying a regulated air flow by an air flow source to the speaker enclosure under test; regulating the air flow to obtain a negative gauge test pressure level in the speaker enclosure; measuring the pressure level in the speaker enclosure to obtain a measured pressure level; waiting for the measured pressure level to reach the test pressure level of twice an extreme pressure level experienced under extreme operating conditions; measuring the mass air flow between the speaker enclosure and the air flow source while maintaining the test pressure level; comparing the mass air flow to a threshold; and if the mass air flow does not exceed a threshold, declaring the speaker enclosure to be leak free. ### Claim 17 A method for measuring speaker enclosure leakage, the method comprising: determining a mass air flow threshold by observing a mass air flow sensor in fluid communication with the speaker enclosure and verifying that a mass air flow below the mass air flow threshold does not produce audible distortions; positioning a speaker opening of a speaker enclosure against a mating plate; assembling a mass flow sensor and air flow regulator serially in fluid communication between the mating plate and an air flow source; applying a regulated air flow by the air flow source through the mass flow sensor and the air flow regulator to the speaker enclosure under test; regulating the air flow to obtain a test pressure level in the speaker enclosure; measuring the pressure level in the speaker enclosure to obtain a measured pressure level; waiting for the measured pressure level to reach the test pressure level; measuring the mass air flow between the speaker enclosure and the air flow source while maintaining the test pressure level; comparing the mass air flow to the mass air flow threshold; and if the mass air flow does not exceed the mass air flow threshold, declaring the speaker enclosure to be leak free.