As more and more ports are removed from our smart devices, it seems that we have one of two options available for using peripherals: either buy a dongle to continue to use wired devices, or switch to Bluetooth and deal with perpetually maintaining batteries. If neither of these options suits you, though, there’s a third option available as [befinitiv] shows us in this build where he integrates a tiny solar panel to his earbud case to allow them to automatically charge themselves.
To start, he begins by taking apart the earbud case. For those who still haven’t tried out a set of these, they typically charge only when placed inside of their carrying case, which in his case also contains a small battery itself. Soldering wires directly to the battery allow for the battery to charge without as much electrical loss as he would have had if he had connected to the USB pins on the circuit board. Even then, the cell only generates a single volt so he needs a 5V boost converter to properly charge the battery. That came with its own problem, though, as it wouldn’t fit into the case properly. To solve that issue, he desoldered all of the components and deadbugged them together in order to fit the converter into a much smaller space without having to modify the case in any other way.
With all of that done and the small solar cell attached to the case, [befinitiv] has a smart solution to keep his wireless earbuds topped up without having to carry cables or dongles around every day. We’ve seen plenty of interesting solutions to the problem of various electronics manufacturers removing the ubiquitous 3.5 mm headphone jack too, and not all of them have dealt with this problem without certain other quirks arising as a result.
Continue reading “Wireless Earbuds Charge Themselves”
Working in a noisy office can be distracting. To combat the problem in his workplace [Rikard Anglerud] bought himself a pair of 3M ear defenders. They were good, but not quite good enough to completely extinguish the noise, so he inserted the drivers from a pair of cheap headphones and played a low-level white noise. This prototype proved effective, so he returned to the project and produced a much nicer pair that approach much more costly cans in their execution.
[Rikard’s] first set of headphones left something to be desired in the quality department. The second set followed with a pair of better-quality drivers sourced online, and more care was taken with cable routing and in their fitting. Finally some filler was used to remove the moulded 3M branding, and make them look more hi-fi than workwear.
From an audiophile perspective these cans might not approach a very high quality pair because their drivers are unlikely to be matched to the acoustic properties of their enclosures. But it sounds as though he’s achieved an adequate result despite that, and completely satisfied his need to exclude office noise.
Audiophiles have worked diligently to alert the rest of the world to products with superior sound quality, and to warn us away from expensive gimmicks that have middling features at best. Unfortunately, the downside of most high quality audio equipment is the sticker price. But with some soldering skills and a bit of hardware, you can build your own professional-level audio equipment around an ESP32 and impress almost any dedicated audiophile.
The list of features the tiny picoAUDIO board packs is impressive, starting with a 3.7 watt stereo amplifier and a second dedicated headphone amplifier. It also has all of the I/O you would expect something based on an ESP32 to have, such as I2S stereo DAC, an I2S microphone input, I2C GPIO extenders and, of course, a built-in MicroSD card reader. The audio quality is impressive too, and the project page has some MP3 files of audio recorded using this device that are worth listening to.
Whether you want the highest sound quality for your headphones while you listen to music, or you need a pocket-sized audio recording device, this might be the way to go. The project files are all available so you can build this from the ground up as well. Once you have that knocked out, you can move on to building your own speakers.
Continue reading “Professional Audio On An ESP32”
Military headphones, at least the older ones, are like few other sound reproducers. They are an expression of function over form, with an emphasis on robustness over operator comfort. Electrically they most often have high-impedance drivers and annoyingly proprietary connectors for whichever obscure radio system they were a part of.
[John Floren] has a HS-16A headset, the type used by the US military during the Vietnam war. It’s an antiquated design with a dual spring steel headband and on-the-ear ‘phones with no muff for comfort, and a quick bit of research finds that they can be had brand new in their 1960s packaging for somewhere around $20. Their connector is a pair of odd metal pins, and rather than doing what most of us would do and snipping the wire to fit something more useful, he hunted high and low for a TE Connectivity receptacle that would fit them. A short extension and a jack plug allowed him to use these slightly unusual cans.
This isn’t a special hack, but it’s still an interesting read because it sheds a bit of light upon these old-style headphones and reveals that they’re still available for anyone who wants their radio operating to have a retro feel. If you buy a set, you’ll probably still have them decades after more modern pairs have bitten the dust.
Hackaday Editors Mike Szczys and Elliot Williams cover the most interesting hacks over the past week. So much talk of putting computers in touch with our brains has us skeptical on both tech and timeline. We celebrated the 40th Anniversary of the Walkman, but the headphones are the real star. Plus, Verilog isn’t just for FPGAs, you can synthesize 7400 circuits too! Elliot is enamored of an additive/subtractive printing process that uses particle board, and we discuss a couple of takes on hybrid-powered drones.
Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!
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Continue reading “Hackaday Podcast 028: Brain Skepticism Turned Up To 11, Web Browsing In ’69, Verilog For 7400 Logic, 3D Printing In Particle Board”
Forty years ago this month, a product was launched in Japan that would have such a huge impact on the consumer electronics market that we are still using its descendants today. The story goes that one of the Sony founders would listen to music while traveling for the business, and found the company’s existing products cumbersome and awkward so asked his engineers to design something more convenient.
The resulting prototype became the Sony MDL-3L2, a set of miniaturised hi-fi headphones with distinctive foam earpads and a sliding metal headband that in total weighed an astoundingly svelte 45 g. It was paired with a cassette player called a “Walkman” derived from the company’s existing recorder that had been intended for journalists, and went on to sell in the millions. The market for headphones would never be the same again, and if you have a set of lightweight cans in your possession then this was their revolutionary progenitor.
But Hang On, What’s So Special About Headphones?
You probably won’t have heard the Walkman’s 40th anniversary described in those terms in the various reports covering the event, because of course the social impact of the portable music player rather than its headphones is what people remember. The joy of making a mix tape, of listening to The Human League on the bus, and of the adult disapproval of anything involving Kids Having Fun. Previously, music had been a static affair involving bulky record players, but now it could be taken anywhere. The other youth audio icon of that era, the boombox, simply couldn’t match the Walkman, and everybody wanted one.
Continue reading “Forget The Walkman: It’s The Headphones”
It seems a reasonable assumption that anyone who’d be willing to spend a few hundred dollars on a pair of headphones is probably the type of person who has a passion for high quality audio. That, or they work for the government. We’re fairly sure [Daniel Harari] falls into that former category though, given how much thought he gave to adding a decent microphone to his Sennheiser HD650 headphones.
Not happy with the results he got from microphones clipped to his shirt or mounted on a stand, [Daniel] realized what he really wanted was a sensitive boom microphone. This would be close enough to his mouth that it wouldn’t pick up stray noises, but at the same time not obstruct his field of view or otherwise get in the way.
He found a few options on the market which would allow him to mount a boom microphone to his HD650’s, but he didn’t want to stick anything to them and risk scratching the finish so those weren’t really an option. [Daniel] decided to go the DIY route, and eventually settled on a microphone that would mount to the headphone’s existing connector which plugs in at the bottom of the cup.
To make his mount, he 3D printed a two piece clamp that could be screwed together and securely attach to the connector without making any permanent changes. Once he had that base component printed, he salvaged the flexible metallic neck from a cheap USB light and used that to hold the female 3.5mm connector. Into that he’s plugged in a small commercially available microphone that is usually used on voice recorders, which [Daniel] said sounds much better than even the larger mics he had tested.
Finally, he used Sugru to encapsulate the wires and create a flexible strain relief. The whole assembly is very light, easily movable, and perhaps most importantly, didn’t require any modifications or damage to a pair of headphones which have a retail price that could double as a car payment.
It’s been a few years since we’ve seen anyone brave enough to hack their pricey Sennheiser headphones. But in the past we covered a modification which gave them an infusion of Bluetooth and even one that reversed a sneaky manufacturer hardware limitation.