More importantly, the testing phase of headphone designs was shortened significantly, saving costs in the development stages. But with Harman curve, designers could tailor-make headphones targeted at a specific group of listeners with similar sound preferences rather than the usual “shooting in the dark” process. Usually, designers make headphones samples, test them on a targeted group of listeners, then tweak the design and retest until most listeners are pleased. The result was a standard measure of the diffuse-field and free-field headphones’ sound response that enabled sound engineers to design listener-targeted headphones. Harman curve, therefore, targeted to establish standard controlled, double-blind comparative and subjective evaluations that minimized headphone tactile and visual biases such as price, cosmetics, and brand.
Also brands lacked consensus on an industry standard, as is the case with loudspeakers. The whole study aimed at developing controlled listening test methods that sound engineers could use to predict accurate and reliable measures of headphones’ sound preferred by most listeners and their underlying sound attributes like bass, midrange, and treble.Īs Sean Olive noted during the presentation, few published studies on controlled headphone sound measurement existed before. The findings were presented at San Francisco in the 2012 Audio Engineering Society Convention. It resulted from a study done by Todd Welti and Sean Olive of Harman International, which culminated into a paper titled “ The Relationship between Perceptions and Measurement of Headphone Sound Quality”. Harman curve relates the link between perceptions and measurement of headphones’ sound quality. The chart shows the target frequency response of an ideal pair of headphones, which levels they should exhibit, and the correct specialized equipment to measure it. The Harman target curve is a rough approximation of what is acceptable in tonality to disregard individualization for precise tonality and spatial audio. From HiFiGuides What Is The Harman Curve? The more knowledge shared on this topic to the consumer increases pressure on manufacturers to address it and scale the possible solutions to improve the listening experience. Painstaking listener experimentation can only prove practical in determining the ideal setting and positioning to eliminate the concern of diminishing returns and poor audio quality. Specialists can only achieve the desired results when they increase the transparency of sound engineers and their choices for recording. The problem is dynamic and complex, and no improvements have proven convenient to yield excellent results. This variation might even occur during the same listening sessions if the headphone position subtly shifts its sitting position, and you can feel and hear it. Remember that the effect of HRTF synthesis and correction is very minimal in wavelengths with high frequencies.įrom the factors mentioned, it is true to say that there is a significant variation in sensitivity when it comes to headphone placement in every wear. The types of headphones used also play a vital role and are relative to the listener’s anatomy. Some of the most common factors include the recording and mastering techniques used like microphone panning and placement. There are several factors involved regarding how strong sound is processed. The Effects of Equalizing to a Calibration Curve It is almost impossible for both findings to be simultaneously correct, and that is what we aim to discover in our research and conclusions in this article. The truth behind this statement is still arguable as researchers have dedicated over half a century’s work to prove the two parallel strands.Įverybody can agree that the two strands make notable improvements in spatial and tonal reproduction of sound.
One of the most contradictory statements revolving around the study of the Harman target curve is that headphones are better at functioning speakers than speakers, and speakers make better headphones than headphones.