Aural ID from Genelec: Making headphones like stereo?

[Hephaestus]

Great to see you here Thomas - I did not know you were a member!
I have enjoyed your blog posts tremendously at Genelec site - dangerous decibels being the most important one.

 

[Phorize]

Thanks for prod, oivavoi. I have primarily considered binaural personalisation from basic human and pro perspectives, so bear with me for maybe going off on a tangent in relation to this forum.

If two people listen in the same room, they are able to precisely discuss what they hear. That is not the case if they share a pair of headphones. Experienced audio engineers - like audiophiles - are highly active listeners, making full use of e.g. outer ears, efferent pathways to the inner ears, movements and any cross-modal amplification they can get. Here are two brief summaries about such issues,

https://www.genelec.com/-/how-does-it-sound-on-headphones-personalised-headphone-listening-•-part-ii
https://www.genelec.com/-/professional-listening

Aural ID replaces a headphones' one-size-fits-all frequency response with a custom compensation, based on an approximation of the actual listener’s external ear, head and upper torso features. That is, however, only a first step towards a natural listening experience.

A processor then needs to calculate direct sound and room reflections, based on the >800 angles of arrival in your personal map (a SOFA file). Furthermore, movements need to be taken into account for low latency audio processing updates. Finally, cross-modal amplification (seeing the same environment you hear, balance, acceleration, body posture, smell, temperature etc.) affects our listening experience.

While the Smyth Realiser actually addresses many of those points in an integrated solution, Aural ID is currently more of as an academic tool for investigating various factors of binaural reproduction systematically. For easy home listening, a hedonistic approach like Harman’s target curves, is one way of qualifying a generally agreeable headphone listening experience.

@Thomas Lund this is really interesting. This is a hopelessly naive question, but how much of a conceptual and technical stretch would it be to get to a place where compensation could be made for cochlear performance and related neurology, say by inputting data from diagnostic auditory brainstem response. Won't be released this year I know!

 

[Thomas Lund]

@Phorize, important pieces to the puzzle of sensing have been discovered/confirmed in recent years, for instance how much adults reach out actively for (expected) stimuli rather than being merely receivers.

Considering hearing, besides from overt behaviour like head and body movement, inner ears receive constant information from the brain, conditioning our cochleas, through so called efferent pathways. The auditory nerve is very two-way, which makes hearing aids a challenge, let alone cochlear implants. I wouldn’t dare to guess when two-way paths could be established, with anywhere near the same sophistication we are born with.

Looking at the previous reply, it wasn’t to depreciate Harman’s target curves. They work so remarkably well partly because of that efferent tuning feature: Despite different outer ears, we end up with roughly the same sound colour reference, learned through natural, frontal sound. It is more in non-frontal sound personal ear-shape plays a determining role.

 

[Hipper]

https://fongaudio.com/out-of-your-head-software/

I've not used this. Here's a thread on it:

https://www.head-fi.org/threads/out-of-your-head-new-virtual-surround-simulator.689299/

Isn't one of the issues with headphones the distortion of the outer ear. There have been headphones that tried to help with this - the Jecklin Floats being the obvious one (ear speakers as the makers described them). The HD800 with bigger ear pieces presumably also tries to deal with this. I tried the Floats and have the HD800 but they both still give the headphone experience. Both are comfortable to wear (as long as no one sees you with the Jecklin Floats though ).

Same with cross talk. I've used crosstalk hardware in the form of the Meier headphone amp and later the Headroom Blockhead. I never noticed any improvement in the listening experience or less fatigue as the proponents claimed. Indeed according to the Ambiophonics concept, removing crosstalk from stereo speakers gives better stereo sound although I've no experience of this.

I like the headphone sound, especially the detail, and have tried to replicate that with my speakers. The result is a highly treated room (including many base traps and attempts to reduce front, back and side wall reflections) that gives me a crisp detailed sound, a good stereo image but placed only between the speakers. I like it!