Though there are a few notable exceptions – including the excellent Nuraphones – most headphones on the hi-fi store shelf will deliver a "one size fits all" sonic experience to listeners. But that's not how we hear sounds around us. Finland's Genelec is looking to inject more realism and accuracy into headphone sound reproduction with some software and a smartphone camera.
Exactly how we hear the sounds around us depend on something called the Head Related Transfer Function (HTRF), where the acoustic properties of a person's anatomy affect what sounds reach the eardrums. And since everyone is different, it stands to reason that we all hear sounds differently.
Genelec has come up with a way to determine an individual's HTRF using a smartphone camera and some software smarts. Recording a video as a modern phone's camera moves 360 degrees around the head, shoulders and upper torso creates a detailed 3D model in the Aural ID app.
The video is then uploaded to a web-based calculation service, which converts this information – which includes data on exactly how audio approaches the head from hundreds of different angles – into a personal data file containing all of the modifications necessary for the delivery of accurate and realistic sound to the user's ears. This SOFA file can then be used by audio engines "to precisely render stereo or immersive content via headphone."
Initially, Genelec is pitching the technology at academics and VR games developers, but it could evolve for use in home hi-fi systems too.
"In the same way that our monitor loudspeakers established the sonic reference for professional audio monitoring, and GLM calibration software revolutionized the way studio monitors could be optimized for any acoustic space, we are determined to help bring standards of sonic truthfulness to headphone reproduction," said the company's Siamak Naghian.
"With an increasing number of audio professionals relying on both in-room monitors and headphones, Genelec Aural ID is a significant first step towards the use of headphones for actual reference audio monitoring and listening."
The Aural ID system will be available for purchase during Q2 2019, no pricing details have been given at this time.
Source: Genelec
I discovered that if you play it in stereo into headphones so that the tracks aren't mixed, you get this eerie "movement" of the track from one side to the other as the delayed track overtakes the other even though the 2 tracks are identical and the same volume.
I then realised that we don't tell where a sound is coming from by volume as is usually used in recordings (panning) where something coming from, say, the left is just made louder than the right channel... we tell where it's coming from by its TIME OF ARRIVAL to one ear or the other.
I always wanted to record a song where I used this technique to create the "sound stage" rather than with panning. I will one day if death isn't a rude interruption to my plan. :-)