Gaming Headset Gets Simple Wireless Charging

May 17, 2021 by Tom Nardi 9 Comments

Despite the technology itself being widely available and relatively cheap, devices that offer wireless charging as a feature still aren’t as common as many would like. Sure it can’t deliver as much power as something like USB-C, but for low-draw devices that don’t necessarily need to be recharged in a hurry, the convenience is undeniable.

Sick of having to plug it in after each session, [Taylor Burley] decided to take matters into his own hands and add wireless charging capability to his Turtle Beach Recon 200 headset. But ultimately, there’s nothing about this project that couldn’t be adapted to your own particular headset of choice. Or any other device that charges via USB, for that matter.

To keep things simple, [Taylor] used an off-the-shelf wireless charging transmitter and receiver pair. The transmitter is housed in a 3D printed mount that the headset hangs from, and the receiver was simply glued to the top of the headset. The receiver is covered with a thin 3D printed plate, but a couple turns of electrical tape would work just as well if you didn’t want to design a whole new part.

Once everything was in place, he then ran a wire down the side of the headset and tapped into the five volt trace coming from the USB port. So now long as [Taylor] remembers to hang the headset up after he’s done playing, the battery will always be topped off the next time he reaches for it.

Considering how many projects we’ve seen that add wireless charging to consumer devices, it’s honestly kind of surprising that it’s still not a standard feature in 2021. Until manufacturers figure out what they want to do with the technology, it seems like hackers will just have to keep doing it themselves.

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Using Ikea Guts To Add Sonos Compatibility To A Vintage Speaker

May 15, 2021 by Jenny List 8 Comments

We’re in a fortunate position when it comes to audio gear, because advances in amplifier and signal processing technology have delivered us budget devices that produce a sound that’s excellent in comparison to those of a few years ago. That said, a decent quality device is good whichever decade it was manufactured in, and a speaker from the 1960s can be coaxed into life and sound excellent with a modern amplifier. It’s something [Sebastius] has explored, as he picked up an attractive-looking set of Swedish speakers from the 1960s. Wanting to bring them into the 21st century, he’s upgraded them for Sonos compatibility by hacking in the guts of an IKEA Symfonisk bookshelf speaker.

The speakers themselves looked good enough, but on closer examination they proved to bear the scars of many decades. After testing new wiring and drivers they still had a good sound to them. Their passive crossover meant that hooking them up to a single amplifier is as straightforward as it was decades ago, but a Symfonisk has an active crossover and two amplifiers. Fortunately there’s a neat hack by which those two amplifiers can be combined as one, and this is what he’s done with the resulting Symfonisk electronic package mounted on the reverse of the speaker.

The fate of the original speaker’s broken mid-range and tweeter drivers was a common enough one back in the day as speakers were ill-matched to amplifiers. Too small an amp would need turning up in volume to get a good sound resulting in distortion that would burn out the top end drivers, while too much power would result in the bass drivers being overloaded and failing. It’s unclear whether the drivers in a vintage speaker would be well-matched to an amplifier such as the Symfonisk, but we’re guessing they are safe while run at sensible volumes. Perhaps of more interest is whatever on-board DSP a Symfonisk contains, because while vintage speakers were designed for as flat a response as possible, modern compact speakers use DSP to equalise the frequency and phase responses of otherwise not-very-good-sounding enclosures. If the Symfonisk does this then those adjustments will appear as distortion in the sound of a different cabinet, but the question remains whether that distortion will be significant enough to be detectable by ear.

If the Symfonisk catches your attention, we’ve covered a teardown of it in the past.

Otters Deliver A High Power Stationary Audio Experience

May 12, 2021 by Kerry Scharfglass 20 Comments

Our favorite raft of otters is back at it again with another display of open source audio prowess as they bring us the OtterCastAmp, the newest member of the OtterCast family of open source audio multitools. If you looked at the previous entry in the series – the OtterCastAudio – and thought it was nice but lacking in the pixel count or output power departments then this is the device for you.

The Amp is fundamentally a very similar device to the OtterCastAudio. It shares the same Allwinner S3 Cortex-A application processor and runs the same embedded Linux build assembled with Buildroot. In turn it offers the same substantial set of features and audio protocol support. It can be targeted by Snapcast, Spotify Connect or AirPlay if those are your tools of choice, or act as a generic PulseAudio sink for your Linux audio needs. And there’s still a separate line in so it source audio as well.

One look at the chassis and it’s clear that unlike the OtterCastAudio this is not a simple Chromecast Audio replacement. The face of the OtterCastAmp is graced by a luscious 340×800 LCD for all the cover art your listening ear can enjoy. And the raft of connectors in the back (and mountain of inductors on the PCBA) make it clear that this is a fully fledged class D amplifier, driving up to 120W of power across four channels. Though it may drive a theoretical 30W or 60W peak across its various outputs, with a maximum supply power of 100W (via USB-C power delivery, naturally) the true maximum output will be a little lower. Rounding out the feature set is an Ethernet jack and some wonderfully designed copper PCB otters to enjoy inside and out.

As before, it looks like this design is very close to ready for prime time but not quite there yet, so order at your own risk. Full fab files and some hints are linked in the repo mentioned above. If home fabrication is a little much it looks like there might be a small manufacturing run of these devices coming soon.

Clay Pot MP3 Player Whipped Up With The Freedom-K64F

April 24, 2021 by Lewin Day 13 Comments

In the streaming era, few of us think about MP3s on a day to day basis anymore. Our music collection is managed by warring executives in streaming companies from far-off lands. However, for [vinod], they’re still useful — seeing as he just built himself an MP3 player that fits in a clay pot.

The build is based on the FRDMK64F development board, packing a powerful 120 MHz ARM chip. This has enough grunt to decode MP3s on the fly, using the Helix MP3 decoder library. The MP3s themselves are streamed off an SD card, using the faster SDIO access method rather than relying on slower SPI. Once decoded, the resulting PCM audio data is shifted out via a DAC using the chip’s DMA hardware, allowing for smooth, glitch-free playback. Output to a big woofer is via a 15 W class D amplifier, with the whole rig powered from a USB powerbank.

With all the electronics piled on the back of a big woofer speaker with lashings of hot glue, the final result is quite imposing; all the more so when installed neatly inside a clay pot acting as a bass reflex enclosure. We’ve seen some concrete cast speakers before, but not nearly enough hacker projects in clay. Please rectify this, and inform us once you’ve done so. Thanks in advance — video after the break!

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Mythbusting Tidal’s MQA Format – How Does It Measure Up?

April 21, 2021 by Lewin Day 117 Comments

MQA is an audio format that claims to use a unique “origami” algorithm, promising better quality and more musicality than other formats. At times, it’s been claimed to be a lossless format in so many words, and lauded by the streaming services that use it as the ultimate format for high-fidelity music. With the format being closed source and encoders not publicly available, these claims are hard to test. However, [GoldenSound] wasn’t born yesterday, and set out to test MQA by hook or by crook. The results were concerning. (Video, embedded below.)

To actually put the format through its paces, the only easy way available was to publish music to the Tidal streaming service, which uses the format. [GoldenSound] went this route, attempting to get some test files published. This hit a brick wall when the publishing company reported that the MQA software “would not encode the files”. The workaround? [GoldenSound] simply cut some audio test content into the middle of an acoustic track and resubmitted the files, where they were accepted without further complaint.

Testing with the content pulled from Tidal, [GoldenSound] found concerning evidence that the claims made around MQA don’t stack up. Significant amounts of added noise are often found in the MQA-processed files, and files served from Tidal are clearly not lossless. Additionally, MQA’s “blue light” authentication system, designed to guarantee to listeners that they’re listening to a identical-to-studio release, is demonstrated to be misleading at best, if not entirely fake.

Upon writing to MQA to get a response to his findings, [GoldenSound]’s test files were quickly stripped from Tidal. The company eventually disputed some of the findings, which is discussed in the video. The general upshot is that without open, transparent tools being made publicly available to analyse the format’s performance, it’s impossible to verify the company’s claims.

We’ve had fun looking at audio formats before, from the history of MP3 to musing on digital audio at truly ridiculous sample rates. Continue reading “Mythbusting Tidal’s MQA Format – How Does It Measure Up?” →

You Otter Be Able To Stream That Audio: Open Hardware Eclipses Chromecast Audio

April 6, 2021 by Kerry Scharfglass 43 Comments

When Google halted production of the Chromecast Audio at the start of 2019, there was a (now silent) outcry. Fans of the device loved the single purpose audio streaming dongle that delivered wide compatibility and drop-dead simplicity at a rock bottom $35 price. For evidence of this, look no further than your favorite auction site where they now sell for significantly more than they did new, if you can even find an active listing. What’s a prolific hacker to do about this clear case of corporate malice? Why, reinvent it of course! And thus the Otter Cast Audio V2 was born, another high quality otter themed hack from one of our favorite teams of hardware magicians [Lucy Fauth, Jana Marie Hemsing, Toble Miner, and Manawyrm].

The Otter Cast Audio is a disc about the shape and size of standard Chromecast (about 50mm in diameter) and delivers a nearly complete superset of the original Chromecast Audio’s features plus the addition of a line in port to redirect audio from existing devices. Protocol support is more flexible than the original, with AirPlay, a web interface, Spotify Connect, Snapcast, and even a PulseAudio sink to get your Linux flavored audio bits flowing. Ironically the one thing the Otter Cast Audio doesn’t do is act as a target to Cast to. [Jan] notes that out of all the protocols supported here, actual Cast support was locked down enough that it was difficult to provide support for. We’re keeping our fingers crossed a solution can be found there to bring the Otter Cast Audio to complete feature parity with the original Chromecast Audio.

But this is Hackaday, so just as important as what the Otter Cast Audio does is how it does it. The OtterCast team have skipped right over shoehorning all this magic into a microcontroller and stepped right up to an Allwinner S3 SOC, a capable little Cortex A7 based machine with 128 MB of onboard DDR3 RAM. Pint sized by the bloated standards of a fully interactive desktop, but an absolutely perfect match to juggling WiFi, Bluetooth, Ethernet, and convenient support for all the protocols above. If you’re familiar with these hackers’ other work it won’t surprise you that what they produced here lives up to the typical extremely high quality bar set by such wonders as this USB-C adapter for JBC soldering iron handles and this TS-100 mainboard replacement.

It sounds like a small production run might be on order in the future, but until then production files optimized for a particularly popular Chinese manufacturer are provided, with complete BOM and placement files. It sounds like turnkey production costs from that manufacturer are a shockingly reasonable $10 (total) per unit with most components, and come to a still-reasonable $22 with the remaining self-sourced components manually installed.

For a demo of the finished goods, check out the tweet embedded after the break.

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Wooden You Love To Build A Ribbon Microphone?

March 18, 2021 by Dan Maloney 11 Comments

Carbohydrate foams derived from dead trees are not the first material that springs to mind when considering building audio equipment. But really, there’s no reason not to explore new materials for jobs normally reserved for metal or plastic, and when pulled off right, as with this wooden ribbon microphone, the results can both look and sound great.

To be fair, there are plenty of non-wood components in [Frank Olson]’s replica of a classic RCA model 44 microphone. After all, it’s hard to get wood to exhibit the electromagnetic properties needed to turn acoustic energy into electric currents. But that doesn’t mean that wood, specifically walnut veneer, isn’t front and center in this design. [Frank] worked with thin sheets of veneer; cut into shape with a commercial vinyl cutter and stacked up with alternating grains, the wood was glued up with copious cyanoacrylate adhesive to form a plywood of sorts. The dogbone-shaped body was fitted with two neodymium magnets, leaving a gap just wide enough for the microphone’s ribbon diaphragm. That was made from a thin piece of aluminum foil that was corrugated using a DIY crimp roller. Suspended between the magnets and connected to leads, the mic element was adorned with a wood and fabric windscreen and suspended from elastic bands in a temporary frame for testing. The narration on the video below was recorded with the mic, which sounds quite nice to our ears.

We’ve seen ribbon microphones before, as well as wooden microphones, but this is the first time we’ve seen a wooden ribbon microphone. It looks as though [Frank] has more work he wants to do to finish it off properly, and we eagerly await the finished product.

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