A Wireless Speaker Pair From Dead Earbuds

May 5, 2021 by Danie Conradie 23 Comments

Building a Bluetooth speaker is easy with the availability of cheap Bluetooth receivers, but surprisingly there isn’t a simple way to build a pair of truly wireless stereo speakers. [Matt] from DIY Perks realized that modern Bluetooth earbuds contain all the electronics to do just that.

Due to the popularity of these earbuds, a broken pair can be picked up very cheaply on eBay. Usually, it’s only the battery or speaker unit that give out, neither of which are required for this build. [Matt] goes through the process of taking a pair of earbuds apart, and then soldering on battery and speaker wires. The speaker wires are connected to an audio amp, which drives a mid-range and treble speaker driver, and a subwoofer. The outputs to the amp are also filtered to match the speakers. Power is provided by a set of four 18650 cells.

[Matt] housed the driver and electronics in some attractive CNC machined wood enclosures. In the video, he places a lot of emphasis on properly sealing all the gaps to get the best possible audio quality. As with all of his projects, the end result looks and performs like a high-end commercial product. We’re almost surprised that he didn’t add any brass to the speakers, as he did on his USB-C monitor or PS5 enclosure build. Continue reading “A Wireless Speaker Pair From Dead Earbuds” →

Soundbar Bested By Virtual Android Bluetooth Sniffer

May 2, 2021 by Tom Nardi 12 Comments

Out of the box, the Yamaha YAS-207 soundbar can be remotely controlled over Bluetooth, but only when using a dedicated application on iOS or Android. Users who want to command their hardware with their computer, or any other Bluetooth device for that matter, are left out in the cold. Or at least they were, before [Wejn] got on the case.

To capture the communication between the soundbar and the application, [Wejn] first installed Android-x86 in a virtual machine on his computer and then enabled the “Bluetooth HCI snoop log” within Developer Settings. From there, a netcat command running on the virtual Android device continually sent the contents of the btsnoop_hci.log file out to Wireshark on his Linux desktop. As he hit buttons in the Yamaha application, he could watch the data come in live. We’ve seen plenty of people use Android’s integrated Bluetooth packet capture in the past, but never quite like this. It’s certainly a tip worth mentally filing away for the future.

The Pi can now control the TOSLINK connected speakers.

From there, things move pretty quickly. [Wejn] is able to determine that the devices are communicating over a virtual serial port, and starts identifying individual command and response packets. It turns out the commands closely mirror the NEC IR codes that he’d previously decoded on a whim, which helped clear things up. Once the checksum was sorted out, writing some code that can talk to the soundbar from his Raspberry Pi media player was the next logical step.

[Wejn] combined this with the Shairport Sync project, which lets the Raspberry Pi turn on the speaker and switch the input over when he wants to stream AirPlay from his phone. But of course, the same technique could be applied to whatever source of digital audio captures your fancy.

This is one of those posts you should really read in its entirety to truly appreciate. While every device is going to be different, the basic principles and workflow that [Wejn] demonstrates in this project will absolutely be useful in your own reverse engineering adventures. If you’re more of a visual learner, we recently covered a series of YouTube tutorials that cover sniffing BLE devices that’s not to be missed as well.

Lamps Double As Secret Surround Sound Speakers

April 28, 2021 by Tom Nardi 23 Comments

Combined with today’s massive flat panel displays, a nice surround sound system can provide an extremely immersive environment for watching movies or gaming. But a stumbling block many run into is speaker placement. The front speakers generally just go on either side of the TV, but finding a spot for the rear speakers that’s both visually and acoustically pleasing can be tricky.

Which is why [Peter Waldraff] decided to take a rather unconventional approach and hide his rear surround sound speakers in a pair of functioning table lamps. This not only looks better than leaving the speakers out, but raises them up off the floor and into a better listening position. The whole thing looks very sleek thanks to some clever wiring, to the point that you’d never suspect they were anything other than ordinary lamps.

The trick here is the wooden box located at the apex of the three copper pipes that make up the body of the lamp. [Peter] mounted rows of LEDs to the sides of the box that can be controlled with a switch on the bottom, which provides light in the absence of a traditional light bulb. The unmodified speaker goes inside the box, and connects to the audio wires that were run up one of the pipes.

In the base, the speaker and power wires are bundled together so it appears to be one cable. Since running the power and audio wires together like this could potentially have resulted in an audible hum, [Peter] only ran 12 VDC up through the lamp to the LEDs and used an external “wall wart” transformer. For convenience, he also put a USB charging port in the center of the base.

When speakers or surround sound systems pass our way, it’s usually because some hacker has either made a set from scratch, or has added some new and improved capabilities to their existing gear. This project may be a bit low-tech compared to some that have graced these pages, but it’s undoubtedly a clever and unexpected solution to the problem, and that’s a hack in our book.

Continue reading “Lamps Double As Secret Surround Sound Speakers” →

MicroLEDs: Lighting The Way To A Solid OLED Competitor

April 12, 2021 by Maya Posch 59 Comments

We’re accustomed to seeing giant LED-powered screens in sports venues and outdoor displays. What would it take to bring this same technology into your living room? Very, very tiny LEDs. MicroLEDs.

MicroLED screens have been rumored to be around the corner for almost a decade now, which means that the time is almost right for them to actually become a reality. And certainly display technology has come a long way from the early cathode-ray tube (CRT) technology that powered the television and the home computer revolution. In the late 1990s, liquid-crystal display (LCD) technology became a feasible replacement for CRTs, offering a thin, distortion-free image with pixel-perfect image reproduction. LCDs also allowed for displays to be put in many new places, in addition to finally having that wall-mounted television.

Since that time, LCD’s flaws have become a sticking point compared to CRTs. The nice features of CRTs such as very fast response time, deep blacks and zero color shift, no matter the angle, have led to a wide variety of LCD technologies to recapture some of those features. Plasma displays seemed promising for big screens for a while, but organic light-emitting diodes (OLEDs) have taken over and still-in-development technologies like SED and FED off the table.

While OLED is very good in terms of image quality, its flaws including burn-in and uneven wear of the different organic dyes responsible for the colors. MicroLEDs hope to capitalize on OLED’s weaknesses by bringing brighter screens with no burn-in using inorganic LED technology, just very, very small.

So what does it take to scale a standard semiconductor LED down to the size of a pixel, and when can one expect to buy MicroLED displays? Let’s take a look. Continue reading “MicroLEDs: Lighting The Way To A Solid OLED Competitor” →

Taking A Peek Inside The Newest Echo Show 10

April 9, 2021 by Tom Nardi 26 Comments

When Amazon released the original Echo, it was a pretty simple affair. Cylinder, some LEDs on top, done. Then they came out with the Echo Dot, which was basically the same thing, but shorter. It seemed like there was a pretty clear theme for awhile, but then at some point Amazon decided it would be a good idea to start producing Echo devices in every form factor imaginable, from wall plugs to literal sunglasses, and things got a lot more complicated. As a perfect example, take a look at this teardown of the third generation Echo Show 10 by [txyzinfo].

Granted the base still looks a bit like the Echos of old, but the family resemblance stops there. As you can probably gather from the name, the Show features a high resolution 10.1 inch LCD panel, greatly improving the number and type of advertisements Amazon is able to force on the user. In true Black Mirror fashion, there’s even a brushless motor in the base that allows the machine to rotate the display towards the user no matter how hard they try to escape.

A salvageable part if there ever was one.

The teardown is presented with no commentary; in both the video below and on the Hackaday.IO page, all you’ll find are clear and well-lit images of the device’s internals. But for those who are just interested in what the inside of one of these $250 USD gadgets looks like, that’s all you really need.

At this point, it doesn’t seem like [txyzinfo] is trying to reverse engineer the Show or figure out how it all works, and looking at the complexity of that main board, we’re not surprised. Still, it’s a marvel to look at all the hardware they packed into such a relatively small device.

If you’re looking for a more technical examination at the newer Echo devices, [Brian Dorey] did some impressive poking around on the third generation Dot in 2019 and [electronupdate] went as far as decapping a few of the chips inside the Flex. On the software side of things, check out the recent efforts to craft an open source firmware for the original Echo.

Continue reading “Taking A Peek Inside The Newest Echo Show 10” →

Custom Built 12-Port A/V Switch Keeps CRT Well Fed

March 30, 2021 by Tom Nardi 5 Comments

Classic gaming aficionados who prefer to play on real hardware know the struggle of getting their decades-old consoles connected to a modern TV. Which is why many gamers chose to keep a contemporary CRT TV around for when they want to take a walk down memory lane. Unfortunately those old TVs usually didn’t offer more than a few A/V ports on the back, so you’ll probably need to invest in a A/V switch to keep them all hooked up at once.

That’s the situation [Thomas Sowell] found himself in, except he couldn’t find one with enough ports. Rather than chain switches together, he decided to build his own custom 12-port console selector. With an integrated amplifier to keep everything looking sharp, a handsome walnut and metal enclosure, and a slick graphical interface that shows the logo of the currently selected console on a Vacuum Fluorescent Display (VFD), the final product is a classic gamer’s dream come true.

To switch the audio [Thomas] is using a pair of ADG1606 16-channel analog multiplexers, while video is shuffled around with four MAX4315 8-channel video multiplexer-amplifiers. The math might seem a bit off at first, but he’s using one ADG1606 for each stereo channel and since the switch is for S-Video, each device has a luminance and color signal that needs to be handled separately. The multiplexers are flipped with a ATmega2561 microcontroller, which is also responsible for reading user input from a rotary encoder on the front of the case and displaying the appropriate console logo on the 140×32 Noritake VFD.

You may be surprised to find that [Thomas] considered himself an electronics beginner when he started this project, and that this is only the second PCB he’s ever designed. Was this a bold second project? Sure. But it also speaks to how far DIY electronics has come over the last years. Powerful open source tools, modular components, and of course a community of creative folks willing to share their knowledge and designs, has gone a long way towards redefining whats possible for the individual hacker and maker.

Continue reading “Custom Built 12-Port A/V Switch Keeps CRT Well Fed” →

A Hi-Fi Speaker From Some Foil And Magnets

March 22, 2021 by Stephen Ogier 44 Comments

In the world of speakers, mass is the enemy of high frequency response. In order to get the crispest highs, some audiophiles swear by speakers in which the moving element is just a thin ribbon of metal foil. As the first step towards building a set of ribbon headphones, [JGJMatt] has designed a compact ribbon speaker made from aluminum foil.

A 3D-printed body holds six permanent magnets, which produce the static magnetic field necessary for the speaker to work. The sound itself is produced by a corrugated aluminum diaphragm made by taking a strip of foil and creasing it with a gear. Aluminum is difficult to solder, so electrical contact is made with a couple of short segments of copper tape. A little Blu Tack and glue hold it all together, and the result is stunning in its simplicity.

Check out the video after the break to hear how it sounds. If you want to try this yourself, it’s important to remember that ribbon speakers have very low input impedances (0.1 Ω for this design), so in order to prevent damage to your amplifier, a transformer or series resistor must be used to bring the impedance up to the 4-8 Ω your amplifier expects.

[JGJMatt] is no newcomer to exotic speaker technology—check out these thin distributed-mode loudspeakers they made! If you’re more interested in recording music than playing it, you might want to read about how a metal ribbon suspended in a magnetic field is used to make incredible microphones. Shout out to [Itay] for the tip. Continue reading “A Hi-Fi Speaker From Some Foil And Magnets” →