Someone needs to invent …

… a tiny, highly directional speaker that can be used in portable devices like laptops, tablets and mobile handsets.

Given the helpful comments that I got last time I made a wish for a product, directing me to exactly what I was after, I am hoping that I’ll get lucky again. But I’ve searched around, and I fear that it doesn’t (yet?) exist.

Normal speakers in portable devices are unsuited to a shared environment when I’m going about a personal activity. For example, if I want to watch a TV program on my laptop, while my wife watches some video on the iPod on the couch next to me, we are going to interfere with each other, making it difficult for either of us to listen to our shows.  Similarly, in an office environment where people are sitting on adjacent desks, it would be great if the sound from any one computer wasn’t audible to the rest of the office. Or alternatively, where many people are on a train and watching video or playing games on their portable devices, reducing the interfering noise would be appreciated.

Headphones are unsuited to both “snacking” type tasks (pick up the device, do something quickly, put it down again) and where a camera is used (as in a video call). If I have to stand up, put down the device, find the headphones, connect them, put them on, then sit back down every time I find I want to watch a video, the result is that I don’t watch videos. And in a video call, while the trend is more and more towards an almost “present” level of quality, seeing the other party wear headphones pretty quickly breaks the illusion. Needing peripherals, such as headphones, usually indicates a compromised experience.

Even if the audio quality is relatively poor, I would still rush out and get a portable device if it had the ability to produce directional audio. I don’t necessarily need high fidelity for watching online video or making a video call.

It appears that the basic technology needed for this sort of speaker is an array of ultrasound generators. You know it has got to be awesome technology if it uses something called ultrasound, right?

From the details on the Explain that Stuff! website, it seems that basically two (ultra) high frequency audio signals are produced, and it is the beat frequency between them that is the actual audio that you hear. Because the frequencies are so high, they are highly directional.

I have found only one product on the market that uses this approach – the American Technology Corporation HSS-H450 – which is a foot long and available for the bargain price of US$1,069.62 (strangely, that’s a UK site).  Meanwhile, I have come across a kit that might be used to make your own (if you’re more talented than I am at electronics). Alternatively, there are some less-than-ultrasonic but still directional speakers that I’ve found from Brown Innovations and Dakota Audio. But neither would suit embedding in an iPad, let alone an iPod.

So, I continue to wait and hope…