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An Examination of Headphone Amplifier Performance Specifications

November 11, 2011

An Examination of Headphone Amplifier Performance Specifications

By John Siau

November 2011

Do Specifications Lie? Do Our Ears Lie? Where does the Truth Lie?

Recording Engineers and Audiophiles often distrust audio measurements and specifications. It is not uncommon to hear claims that a product measures poorly but sounds good. Occasionally we also hear claims that a product measures well but sounds bad.

This whitepaper documents significant differences between three headphone amplifiers that have nearly identical published specifications.

All three products have a high-quality headphone output with very low output impedance, high drive capability, low distortion, and a flat frequency response. The published specifications strongly suggest that it should be impossible to hear any difference between these products. Nevertheless, in our informal listening tests, we had the distinct impression that there were significant sonic differences between these products when listening to music.

We replicated the manufacturers' tests and found that the published specifications were accurate and correct. All three manufacturers followed standard measurement procedures and provided accurate specifications.

This paper shows some additional measurements which expose significant differences that do not appear in traditional published specifications:

Download Paper (PDF)



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