He was impressed then and said so, acknowledging that if it could be taken through to a finished product it would be pretty revolutionary. He has reiterated that in this latest review update.
"... Audio Pixels, founded in July 2006, has developed a revolutionary technological platform for reproducing sound. Its patented Digital Sound Reconstruction platform employs ultrasonic techniques to generate sound waves directly from a digital audio stream using MEMS rather than conventional speakers. This innovation, still in the developmental phase, promises speaker products that deliver better performance than conventional speaker technologies, in a 1mm thick package. During 2020 Audio Pixels has made considerable progress, getting ever closer to releasing its new technology. ..."
These are not conceivably the kind of statements that could or would be made by someone of that level of expertise and industry credibility if the whole thing was some kind of a con. It is entirely unreasonable to imagine it could be so.
In 2015 he particularly pointed out that the DSR technology used by AP would eliminate the limitations that other MEMS speakers have and will continue to struggle with. Any microspeaker with a small membrane simply cannot move enough air to generate the kind of sound pressure level (SPL) that a voice coil speaker can. Even in this most recent review by Mike Klasco he indicates that compared with traditional voice coil designs the largest SPL was still relatively small ("... The air moving power of MEMS speakers is significantly less than even the lowest-performance microspeakers. ..."). Even the best commercial units currently available can deliver up to 120dB within the ear (e.g. Usound's Conamara), which is why most of them are aimed at headphones, earphones, and hearables.
Note in contrast the stated value for AP (centre of the yellow range) is achieving SPL of >70dB at 1 metre, i.e. too loud for use in the ear. And this can be increased by adding more speakers to an array. That takes it onto a par with voice coil speakers, at which point it becomes a clear competitive product for them.
Interestingly, AP has found a way to make their MEMS quiet enough for them to be used in headphones.
Nothing that has been put out by the company, or by those with expertise in the field, could provide any grounds to believe this technology is either a fraud or a flop.
(20min delay)