Bone Conducting Headphones Built Into Eye Glasses

April 18, 2019 by Jenny List 21 Comments

There are times when being seen to listen to music through headphones might get you into trouble. For these moments, reach for a handy solution: bone conduction speakers that discreetly pipe the music to your eardrums through the bone of your skull. [Samuel] wanted just such a covert music listening device, so created his own in a set of 3D-printed glasses.

He first tried using an Adafruit bone-conducting transducer but found that to be too bulky. What you see here is a smaller module that [Samuel] found on AliExpress (search for bone conduction module). The GD-02 is much smaller and thus more suitable for hiding in the arm of a pair of glasses. For the rest of the electronics he used a PCB and battery from a donated set of broken Bluetooth headphones, a space for which he was able to conceal easily in the 3D-printed frame of the glasses. The battery is in one arm and the board in the other, and he says the wiring was extremely fiddly.

The result is a surprisingly svelte set of specs that you might not immediately think concealed some electronics. His choice of bright yellow filament might give the game away, but overall he’s done a great job. This certainly isn’t the first bone conduction project we’ve shown you, some of the others have used motors instead of bone conduction transducers.

Squeezebox Comes To The ESP

March 31, 2019 by Jenny List 11 Comments

Streaming music may now come from somewhere in the cloud to an app on your phone and be sent to the client built in to almost every entertainment device you own, but there was a time when the bleeding edge lay in dedicated streaming device that connected to your existing set-up. One of the players in this market was Logitech with their Squeezebox line of products, and while the original hardware may have been discontinued it remains very much alive among its dedicated userbase due to the free nature of the Logitech Media Server software and implementations of the slimproto streaming protocol in players. Now you can create a network player on about as cheap hardware as it is possible to find, because [Bgiraut] has produced a client for the ESP32 and ESP8266.

The software can be found on GitHub, and comes with the warning that it’s an early proof-of-concept rather than a polished release. It has two options for playback that both require a little bit of extra hardware, an I2S DAC for uncompressed streams or a VS1053 codec module for compressed ones, but neither of those need be expensive.

You can find Logitech Media Server from its download page, and give this device a try. Meanwhile we’ve covered many Squeezebox implementations, including ones on the Raspberry Pi, and the PogoPlug.

Thanks [joyofdivisions] for the tip.

The CD Is 40, The CD Is Dead

March 19, 2019 by Jenny List 127 Comments

The Compact Disc is 40 years old, and for those of us who remember its introduction it still has that sparkle of a high-tech item even as it slides into oblivion at the hands of streaming music services.

There was a time when a rainbow motif was extremely futuristic. Bill Bertram (CC BY-SA 2.5)

If we could define a moment at which consumers moved from analogue technologies to digital ones, the announcement of the CD would be a good place to start. The public’s coolest tech to own in the 1970s was probably an analogue VCR or a CB radio, yet almost overnight they switched at the start of the ’80s to a CD player and a home computer. The CD player was the first place most consumers encountered a laser of their own, which gave it an impossibly futuristic slant, and the rainbow effect of the pits on a CD became a motif that wove its way into the design language of the era. Very few new technologies since have generated this level of excitement at their mere sight, instead today’s consumers accept new developments as merely incremental to the tech they already own while simultaneously not expecting them to have longevity.
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Python Script Sends Each Speaker Its Own Sound File

February 14, 2019 by Anool Mahidharia 8 Comments

When it comes to audio, the number of speakers you want is usually governed by the number of tracks or channels your signal has. One for mono, two for stereo, four for quadrophonic, five or more for surround sound and so on. But all of those speakers are essentially playing different tracks from a “single” audio signal. What if you wanted a single audio device to play eight different songs simultaneously, with each song being piped to its own speaker? That’s the job [Devon Bray] was tasked with by interdisciplinary artist [Sara Dittrich] for one of her “Giant Talking Ear” installation project. He built a device to play multiple sound files on multiple output devices using off the shelf hardware and software.

But maybe a hack like this could be useful in many applications other than just art installations. It could be used in an Escape room, where you may want the various audio streams to start in synchronicity at the same time, or as part of a DJ console, sending one stream to the speakers and another to the head phones, or a game where you have to run around a room full of speakers in the right sequence and speed to listen to a full sentence for clues.

His blog post lists links for the various pieces of hardware required, although all of it is pretty generic, and the github repository hosts the code. At the heart of the project is the Sounddevice library for python. The documentation for the library is sparse, so [Bray]’s instructions are handy. His code lets you “take a directory with .wav files named in numeric order and play them over USB sound devices attached to the host computer over and over forever, looping all files once the longest one finishes”. As a bonus, he shows how to load and play sound files automatically from an attached USB drive. This lets you swap out your playlist on the Raspberry Pi without having a use a keyboard/mouse, SSH or RDP.

Check the video after the break for a quick roundup of the project.

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Those Voices In Your Head Might Be Lasers

February 1, 2019 by Al Williams 21 Comments

What if I told you that you can get rid of your headphones and still listen to music privately, just by shooting lasers at your ears?

The trick here is something called the photoacoustic effect. When certain materials absorb light — or any electromagnetic radiation — that is either pulsed or modulated in intensity, the material will give off a sound. Sometimes not much of a sound, but a sound. This effect is useful for spectroscopy, biomedical imaging, and the study of photosynthesis. MIT researchers are using this effect to beam sound directly into people’s ears. It could lead to devices that deliver an audio message to specific people with no hardware on the receiving end. But for now, ditching those AirPods for LaserPods remains science fiction.

There are a few mechanisms that explain the photoacoustic effect, but the simple explanation is the energy causes localized heating and cooling, the material microscopically expands and contracts, and that causes pressure changes in the sample and the surrounding air. Saying pressure waves in air is just a fancy way of explaining sound.

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Raspberry Pi Jukebox Hits All The Right Notes

January 22, 2019 by Tom Nardi 2 Comments

We (and by extension, you) have seen the Raspberry Pi crammed into nearly every piece of gear imaginable. Putting one inside a game console is so popular it’s bordering on a meme, and putting them into old stereos and other pieces of consumer electronics isn’t far behind. It’s always interesting to see how hackers graft the modern Raspberry Pi into the original hardware, but we’ll admit it can get a bit repetitive. So how about somebody scratch building an enclosure for their jukebox project?

[ComfortablyNumb] took the road less traveled when he created this very nice wooden Raspberry Pi enclosure in the shape of an eighth note. Stained and varnished and with a nice big touch screen in the middle to handle the controls, it’s an attractive and functional piece of home audio gear that we imagine most people would be happy to hang on their wall.

The process starts by printing out the desired shape on a piece of paper to use as guide, and then gluing together strips of wood to create the rough outline. Then the surface was thoroughly sanded to bring all of the strips of wood to the same level, and the final design was cut out. On the back of the note, [ComfortablyNumb] boxed out an area to hold the Waveshare seven-inch touch screen panel and the Raspberry Pi itself.

Having seen so many projects where the Pi is rather unceremoniously shoehorned into another device, it’s refreshing to see the results of a purpose-built enclosure. Since [ComfortablyNumb] was able to build the electronics compartment to his exact dimensions, the final result looks exceptionally clean and professional. Not a drop of hot glue to be seen. It also helps that this build only required the Pi and the display; as the device is meant to be plugged into an existing audio setup, there’s no onboard amplifier. The audiophiles out there might recoil in horror, but adding a dedicated digital to analog converter (DAC) would be easy enough to add if the stock audio on the Pi isn’t good enough for you.

The project is finished off with stain and several coats of varnish to get that deep and rich color. We don’t often find ourselves working with dead trees around these parts, but we’ve got to admit that the final product does look quite handsome. Certainly beats the LEGO cases many of our Pi projects live in.

If you’re looking for more wooden-encased Pi jukeboxes, you might enjoy this somewhat abstract magstripe-based take on the concept. Of course, we’ve also seen our fair share of actual jukeboxes receive a Raspberry infusion over the years.

[via /r/raspberry_pi]

Somewhere Down In Africa Toto Is Playing On Loop

January 19, 2019 by Drew Littrell 26 Comments

Amidst the vast expanse of sand dunes in the Namib desert, there now exists a sound installation dedicated to pouring out the 1982 soft rock classic “Africa” by Toto. Six speakers connected to an MP3 player all powered by a few solar powered USB battery packs, and it is literally located somewhere down in Africa (see lyrics). The whole project, known as TOTO FOREVER, was the creation of film director [Max Siedentopf] who himself grew up in Namibia.

“I set up a sound installation which pays tribute to probably the most popular song of the last four decades…and the installation runs on solar batteries to keep Toto going for all eternity.”

– Max Siedentopf, Creator of TOTO FOREVER

[Siedentopf] certainly chose a song that resonates with people on a number of levels. Toto’s “Africa” was one of the most streamed songs on YouTube in 2017 with over 369 million plays. The song continues to reach a new generation of fans as it has also been the subject of a number of internet memes. Though those local to the sound installation have had some less than positive things to say. [Siedentopf] told BBC, “Some [Namibians] say it’s probably the worst sound installation ever. I think that’s a great compliment.”

The idea of the installation “lasting for all eternity” will certainly be difficult to achieve since the components most certainly lack any serious IP rating. The audio player itself appears to be a RHDTShop mp3 player that according to its Amazon listing page, has three to four hours of battery life per charge. Considering the size of those solar cells the whole thing will probably be dead in a week or two (it is in a desert after all), but no one can deny the statement TOTO FOREVER makes. Below is some footage of the art piece in action taken by the artist himself.
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