RP203 - Myth-Busting the 3:1 Compression Limit: Optimized Audibility with Preserved Sound Quality

Thursday, March 31, 2022

3:45 PM – 4:15 PM CT

Location: 127

Earn 0.05 CEUs

Lead Presenter(s)

Pragati Rao Mandikal Vasuki, PhD

Senior Research Audiologist and Hearing Scientist
Earlens corporation
Menlo Park, California

Disclosure: Financial Disclosures: Earlens Corporation- Employment, Intellectual Property / Patents, Stockholder/Ownership Interest (excluding diversified mutual funds)
Non-Financial Disclosures: I do not have any relevant non-financial relationships with anything to disclose.

PDF Slides

Presenter(s)

Drew Dundas, PhD

Chief Technology Officer
Earlens Corporation, California

Disclosure: Financial Disclosures: Earlens Corporation- Employment
Non-Financial Disclosures: I do not have any relevant non-financial relationships with anything to disclose.
Suzanne P. Levy, PhD

Sr. Dir. Professional Education and Clinical Research
Earlens Corporation
Belmont, California

Disclosure: Financial Disclosures: Earlens Corporation- Employment, Ownership Interest includes stock, stock options, patent or other intellectual property
Non-Financial Disclosures: I do not have any relevant non-financial relationships with anything to disclose.
EM

Elizabeth N. Mitchell, AuD

Manger of Audiology Support Services
Earlens Corporation
Menlo Park, California

Disclosure: Financial Disclosures: Earlens Corporation- Employment, Ownership Interest includes stock, stock options, patent or other intellectual property
Non-Financial Disclosures: I do not have any relevant non-financial relationships with anything to disclose.

Abstract: Common clinical wisdom argues that compression ratios (CRs) higher than 3:1 will result in poor sound quality for hearing aid users. However, maximizing audibility while maintaining comfort in sensorineural hearing loss often requires significantly higher CRs. When implemented in a direct drive hearing aid, CAM2 commonly prescribes CRs as high as 10:1, benefitting the user by maximizing audibility of soft speech cues, particularly in the high frequencies. This study evaluated audibility and subjective sound quality with high CRs, demonstrating that audibility and sound quality can be maintained with high CRs if time constants are carefully optimized.

Learning Objectives:

Describe the goals and assumptions of the CAM2 high-frequency fitting algorithm.
Discuss the impact of compression ratios and time constants on sound quality.