Google has released an experimental new extension for its Chrome browser to allow users to share links to anyone within hearing distance by using sound.

The new extension, called Tone, was built by Googlers in an afternoon, according to Google interaction researcher Alex Kaufmann and software engineer Boris Smus.

However, teams at the Mountain View headquarters soon found Tone quite useful, so Google decided to release it as an official extension, although one that is still in experimental mode.

Tone works by sending links to other computers running on Chrome with the extension installed. Users simply click on the blue Tone button on their browsers to initiate a series of beeping sounds that will send the link to other users. If all goes well, recipients get a notification that a link has been sent to them with the option of opening the link.

However, things don't go well all the time. Kaufmann and Smus explain that the sounds Tone uses mimic human voice, thus it has the same limitations. For one thing, the human voice rarely passes through solid barriers, such as walls, unless it is extremely loud. Tone is also restricted to sending links to computers equipped with a decent microphone and placed within earshot.

Also, multiple factors can affect the ability of Tone to transmit the sounds effectively, such as the interference of background noise and the sensitivity, or lack thereof, of the computers that are the target recipients.

"Not every nearby machine will always receive every broadcast, just like not everyone will always hear every word some says," noted Kaufmann and Smus.

It isn't so difficult to troubleshoot Tone, though. Google says users can easily resend the link and increase the volume of the sound to make sure other computers receive the link if they didn't during the first time.

Initially, Google developed an efficient audio transmission scheme that didn't sound too good, so Tone's makers decided to use sound that is beyond the range audible to human ears. However, this did not work out so well since most computer microphones and video conferencing systems are optimized to recognize the human voice, so Google used "dual-tone multi-frequency signaling" that improved reliability, and even made Tone work with Google Hangouts.

While most users will probably not find a lot of practical everyday uses for Tone, schools and offices will likely find Tone a useful new extension. At Google, for instance, teams of collaborators working on a single project have used Tone to share documents at meetings and while working on projects, and to send links to team members without interrupting conversations.

Photo: Marcin Wichary | Flickr