Ann: Quarterly Activities/Appendix 4C Cash Flow Report, page-174

Thanks Sprice. Yep. Very clever ideas.

Essentially the bottom membrane pumps out a fixed ultrasonic frequency, while the top membrane acts as a 'gate' to allow bursts of it to pass through as pressure = sound pulses. Modulate this and you get an audio signal in human hearing range.

From memory this is a bit reminiscent of USound's system. Similar but not the same mechanism. As you say, its not quite coming off the production line yet, and as we know, there's always potential for a few 'slips 'twixt cup and lip' as they say. I expect AP will still beat them to market with a commercial product despite AP's current delays.

I don't think they were saying AP is direction sensitive and they were not. But the reverse is definitely true, their system can only go in one direction, which is perpendicular to the device. What comes out is essentially a mono-directional sound beam. When the element array is controlled by its ASIC all the elements are in phase. AP's array + DSR permits directional sound streams (plural) to be created, i.e. different signals to different hearers. I would also expect that it would be quite a task to increase the SPL by adding additional devices in the way that AP's DSR permits because every chip would have to be exactly planar and parallel and perfectly aligned. That would limit its ability to be useful in a chip array like a room speaker system. It is thus naturally targeted at in and on ear speakers.

Very interesting nonetheless. Smart guys those Israeli physicists!

MEMS speakers are coming one way or another! It's only a matter of time and engineering. All the advantages are there though, as these guys can also see.