Apple audio processing could change the way headphone users experience music
Apple has come up with a way it thinks could provide headphone and earphone users the optimal listening experience, using a variety of signal processing techniques to make the sound seem like it is being heard without the use of headphones at all.

via The Apple Post
Granted by the U.S. Patent and Trademark Office on Tuesday and initially filed on September 22, 2016, the patent for "Spatial headphone transparency" describes ways a pair of headphones could adjust the sound from an audio source, changing the way the user hears it.
Apple uses the term "acoustic transparency," which it also refers to as transparent hearing or a "hear through mode," where a headset picks up ambient sound from the local environment of the wearer then, after processing, includes it in the audio feed that is played to the wearer. If performed correctly, this could make the user's listening experience "as if the headset was not being worn."

In one section, the patent suggests the use of microphones to pick up sounds that the user would have heard if they were not wearing headphones, then for the left and right sides separately processing them through an acoustic transparency filter, before being combined with the audio the user is listening to. The composite audio is then played through the left and right speaker drivers.
The filter in question will attempt to preserve any spatial filtering effects that would occur naturally, such as how the user's head, shoulder, and other anatomical features can affect the timbre and other acoustic elements of the ambient sound. The filter will also attempt to avoid coloring the speaker driver signal, such as reducing resonances at higher frequencies, to accentuate the effect.
In some embodiments, Apple also attempts to use the system to eliminate the effect of headphone-based music being heard "within the user's head," instead making it sound as if it's stemming from speakers positioned directly above the user. This is thought to help reduce any acoustic occlusion with ambient sounds, namely making it easier for the user to identify nearby noises without it clashing with the audio track.

Apple does have experience with audio processing that could potentially make such a system a reality. The adaptive audio function of the HomePod is capable of detecting the environment and optimizing its output to fill a room with sound, regardless of nearby obstacles.
Apple is also rumored to be working on a new headphone project separate from the Beats line, one that could provide noise-cancellation abilities. Thought to be a premium audio peripheral, the headphones are currently speculated to arrive no earlier than the holiday shopping period at the end of 2018.

via The Apple Post
Granted by the U.S. Patent and Trademark Office on Tuesday and initially filed on September 22, 2016, the patent for "Spatial headphone transparency" describes ways a pair of headphones could adjust the sound from an audio source, changing the way the user hears it.
Apple uses the term "acoustic transparency," which it also refers to as transparent hearing or a "hear through mode," where a headset picks up ambient sound from the local environment of the wearer then, after processing, includes it in the audio feed that is played to the wearer. If performed correctly, this could make the user's listening experience "as if the headset was not being worn."

In one section, the patent suggests the use of microphones to pick up sounds that the user would have heard if they were not wearing headphones, then for the left and right sides separately processing them through an acoustic transparency filter, before being combined with the audio the user is listening to. The composite audio is then played through the left and right speaker drivers.
The filter in question will attempt to preserve any spatial filtering effects that would occur naturally, such as how the user's head, shoulder, and other anatomical features can affect the timbre and other acoustic elements of the ambient sound. The filter will also attempt to avoid coloring the speaker driver signal, such as reducing resonances at higher frequencies, to accentuate the effect.
In some embodiments, Apple also attempts to use the system to eliminate the effect of headphone-based music being heard "within the user's head," instead making it sound as if it's stemming from speakers positioned directly above the user. This is thought to help reduce any acoustic occlusion with ambient sounds, namely making it easier for the user to identify nearby noises without it clashing with the audio track.

Apple does have experience with audio processing that could potentially make such a system a reality. The adaptive audio function of the HomePod is capable of detecting the environment and optimizing its output to fill a room with sound, regardless of nearby obstacles.
Apple is also rumored to be working on a new headphone project separate from the Beats line, one that could provide noise-cancellation abilities. Thought to be a premium audio peripheral, the headphones are currently speculated to arrive no earlier than the holiday shopping period at the end of 2018.

Comments
The music would continue playing but at a distinct volume and the speaker's voice came through crystal clear. You had to manually flick a switch of course.
To a degree, this patent is the hi-tech digital version of the same idea.
The idea was that any listener, on axis (ie. between the two speakers) would experience the effect that your right channel would be uniquely coming from the right speaker, as the left channel would "cancel" out. In other words, as we are basically predators, our right ear hears both speakers, so our brain "targets" the speaker source. By using wave cancellation, the right ear would theoretically only hear the right speaker, and the left ear would only hear the left speaker. As long as you remained "somewhat" on axis between the speakers.
On a decent stereo system, the effect was quite impressive, as the true "sound stage" was accurately reproduced, you "heard" sounds coming outside from the physical speaker placement. Blindfolded and given a ping-pong ball gun, people would think that the speaker was 10+ feet to the right, of the right channel. Using Sonic Holography and a set of omni-directional speakers; you could "hear" that the voice was coming from a point to the right of the speaker about 3 feet, and originating about 5 feet off the ground - as if they were in the room playing, live.
So, I'm pretty excited to see where Apple takes this. It's been many years since Bob Carver shook up the audio world; first with his Magnetic Field amplifiers, then with Sonic Holography, then with an asymmetrical tuning system for his FM tuner, and some other stuff that dealt with vinyl records. Bob was quite the genius.
https://www.businessinsider.com/noveto-focused-audio-technology-could-make-headphones-obsolete-2018-6
Between the new bluetooth and wifi standards, focused audio tech, and now potential Apple audio changes its seems like a bad time to make a big investment in expensive headphones or smart-speakers. They could end up as quaint and almost abandoned old-school within just a very few years.
But Apple Watch coupled with AirPods make the best combination I’ve ever seen .
So you’re comparing a simple analog summing amplifier (one of the most basic electronic circuits that have been used for 100+ years) to an advanced digital processing system?
Not the same. At all.
The first three times I went through this I contacted Apple. Since then I'm tired of the same answer: "that shouldn't happen, try resetting from new". It's to the point I just always now keep my phone with me.
But yeah, when it works, the AW3+LTE and airpods are a great combo.
"To a degree, this patent is the hi-tech digital version of the same idea."
But to answer your observation: NO
The Sanyo system simply summed two analog signals together (nothing more than a couple resistors and an op amp). Apples version applies sophisticated digital processing to the audio picked up by the microphones and also to the audio you're listening to in order to alter the soundstage presented to the listener.
Your comment has nothing to do with the article as the technology employed and the desired results have NOTHING in common. It would be the same as me claiming Blumlein had a similar idea back in the 1930's and Apple is just making a modern version.
It's the same as typical comments we see here at AI - bring up an unrelated idea to claim Apple wasn't really the first to do this, and that Apples patent is nothing more than a rehash of an existing idea.
My post had little to do with implementation.
I was about the idea of allowing ambient sounds (in this case speech) into a closed audio space. The 'transparency' Apple is referring to.
I could tell you stories. "Sonic Holography" was an application of the Schroder loudspeaker crossfeed,
to reduce interchannel crosstalk and Blumlein Shuffling to widen the image. Is sounded good, but was very sensitive to seating position.
Rob R.