home entertainment hacks

820 Articles

Fixing A Dodgy Cheap Audio DAC

July 9, 2026 by 14 Comments

One of the attractions of buying at the bottom end of the electronics market by mail order from China is that you never quite know what will come your way. Sometimes it’s a diamond in the rough, while with others it’s a mess. Occasionally along comes something which should work but doesn’t, and that’s the moment when you wonder if you could fix it. [Nyanpasu64] had just such a device, an HDMI to VGA converter with audio that didn’t work. What could be wrong?

The HDMI to VGA chip has an onboard audio digital-to-analog converter (DAC), and it’s a delta-sigma design. This type of DAC is frequently used in audio applications because it works by shifting its switching frequency many times higher than the input sample rate, thus reducing considerably the distortion. This one wasn’t performing as advertised though, and the problem turned out to be that switching frequency being all over the output. Clearly the filter wasn’t working, which led to the design of a new filter. The write-up is therefore an extensive dive into filter design, and in part also a discovery of the effect of impedance on them.

For a super-cheap module to cause so much work, one might ask why not simply spend a few more dollars and get a better one. But had they done that we wouldn’t have seen this write-up, so we’re sticking with team cheap.

We’ve looked at audio DACs, in the past.

Mechanical TV, Without The Benefit Of New Parts

June 29, 2026 by 9 Comments

There are many experimenters who have had a go at a mechanical television, and though there are a few challenges, it’s a relatively straightforward project in 2026. A hundred years ago though it was still beyond the cutting edge of technology, and that’s where [Paul Kocyla] is placing his build. It’s a mechanical TV system, using only parts that would have been available in the 1920s. The project isn’t finished yet, but we suggest following along for some fascinating insights into developments in early electronics.

As it stands he has a wooden chassis, a period power supply and amplifier, a synchronous motor, and of course the Nipkow disk that makes it all possible. The electronics aren’t quite finished, and he’s yet to source a neon lamp. This last part may be particularly tricky, as there were specific flat-plate neon lamps made for this application. It’s interesting to find that the motor would synchronize to the grid frequency and would need to be restarted a few times for the frame to be in the right place.

His last posting contains a particularly interesting nugget of information for anyone using tubes. The amplifier carries a 120 Hz hum, something difficult to trace. The culprit is the early tubes with directly heated cathodes formed from the heaters themselves; they had such a low thermal mass that they would “blink” at 120 Hz if fed with AC. A set of period copper oxide rectifiers solve this by feeding DC to the heaters. There’s a YouTube series to follow, and we’ve placed the most recent one in which he fixes the power supply, below the break.

Back in January, we marked the hundredth anniversary of mechanical TV’s invention. Meanwhile, some of us have been known to experiment in this direction too.

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Make Your Own Loudspeaker From Scratch

June 28, 2026 by 6 Comments

A loudspeaker is a vital component of every device that plays sound, but while its operation is simple, it’s a surprisingly difficult device to build. [Rvanderouderaa] has made an Instructables post showing a speaker design that it’s claimed, had an impedance that varies by volume (Dutch language, Google Translate link).

In all moving-coil speakers, a coil of wire is held in a radial magnetic field. To this is attached a cone, and when a current is passed through the coil the whole thing moves to create the sound. The tricky part of making one comes in making the cone itself, and in particular the suspension system that holds it in place while allowing it to move backwards and forwards. It’s normal for these components to be moulded from thick paper.

This design uses a 3D printed frame and cone, with the 3D printing providing excellent rigidity. The suspension system is a circular corrugated sheet, and it’s made in this case using papier-maché made from wet toilet paper, and a 3D printed mould. We particularly like this technique.

This is an impressive build, simply for having made a recognizable and working speaker in the first place. There’s no demo video so we have no idea how it sounds, but for us the point is more in the construction than the reproduction.

If speakers interest you, we’ve taken an in-depth look at them in the past.

Make That Smart TV Into A Computer

June 25, 2026 by 23 Comments

The smart TV is a fixture in most houses, variously an entertainment portal, corporate data gathering tool, or sometimes an outright spy. It’s a nice monitor with a computer built in, so can that computer be released to do something else? It’s a question [Xen’on] is answering, on an Android-based TV.

The guide is not too different from many others relating to Android phones, with a few quirks. An Android Debug Bridge (ADB) connection is established, root access is gained using Shizuku, and then it’s a case of installing a more conventional Linux front end with the Openbox window manager through Termux. There are some TV-specific things to do with handling power cycles, but the TV is now a usable Linux box.

It’s always good to see someone retrieve the Linux underneath a locked-down device, but the system spec tells the real story. By the looks of things this TV is a few years old as it had an Android version that’s a bit long in the tooth, and thus it also packs an aged version 4.x kernel. Couple that with a more seat-of-your-pants experience compared to a regular distro where many of the annoyances are taken care of, this isn’t an easy route to a trouble free desktop. Instead it has a lot of potential for making the TV what it was intend to be, an entertainment device. Merely one that gives much more software freedom.

Meanwhile, this isn’t the first Termux guide we’ve seen.

Pi Media Player With VCR Vibe Is Perfect For CRTs

June 10, 2026 by 14 Comments

If you have a TV and a Pi, you have the workings of a media center, and you’re not exactly short on options for software. But options are good, so here’s one more by [Anthony Caccese] — a player called 240-MP that explicitly targets CRTs with its retro stylings, released under the GPLv3 license.

Don’t let the name fool you, though. While the blue-and-white styling is very evocative of 90s VCRs, the output isn’t limited to 240p. If you’re running it into a vintage CRT over composite, as [Anthony] does, sure, it’ll do that. If you want to use HDMI on a modern TV, however, that’s an option too, in 4K if that’s your jam. Higher resolution video will need a beefier Pi, of course, but MPV can handle the files, and ultimately this is a wrapper for MPV. You still get the vintage styling, which can do green-and-black as easily as white-and-blue, as well as whatever custom color scheme you want to define. It might not look quite as good if it’s not on a display tube, but we could see this as a good fit for a plasma TV, too.

As you can see in the demo video embedded below, the player is equally happy listing and playing local files — including playlists — or streaming via a PLEX server. Other add-ons, for example to launch emulators, may be forthcoming. Of course, if you’re not willing to wait you could always code them yourself.

Given the roots of this project in old VHS interfaces, we’re somewhat surprised there doesn’t seem to be an option for control via physical tokens. We’ve already seen projects that try and replicate that portion of the VCR magic, though. If it’s not the tapes you miss from back in the day, you can also simulate cable TV.

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Bring Back Your Bose With An ESP32

May 28, 2026 by 41 Comments

It’s become a familiar theme over the last couple of decades — hardware is rendered useless when its manufacturer pulls the cloud service on which it depends. This is particularly annoying when the device is something which shouldn’t need a cloud service to run in the first place, and several manufacturers have found themselves in hot water because of this.

Somewhere in between is the Bose SoundTouch speaker system, which includes a set of six internet radio preset buttons. In early May the service behind them was shuttered, and now here’s [Tostmann] with an ESP32 firmware to bring them back.

As you might imagine, it’s a device that emulates just enough of the now-defunct Bose cloud service to keep the speaker happy, but it has a clever trick up its sleeve. Normally these hacks rely on DNS redirects at the router, but this one avoids that thanks to a diagnostic interface on the Bose unit that allows the rewriting of the server address. The ESP32 does this with its own address, and the speaker is none the wiser.

We like this hack, because of its ingenuity, and because it saves yet another orphaned cloud product from becoming e-waste. This isn’t the first time we’ve seen a manufacturer on the naughty step for these practices.

Header image: TAKA@P.P.R.S, CC BY-SA 2.0.

The History Of Altec Lansing

May 12, 2026 by 21 Comments

If you bought computer audio hardware a few decades ago, you may remember coming across products from Altec Lansing. That you probably haven’t thought of that name in some time doesn’t surprise us, the company has not fared well in recent years and has changed hands multiple times. [The Last Shift] tells the company’s history in a video you can watch below.

James Lansing started Lansing Manufacturing, offering high-end speakers for the fledgling “talkie” movie industry. It had some success, but the depression put them on shaky footing. Meanwhile, a company named All Technical Service Company, or Altec, was a large organization that serviced Western Electric movie theater equipment. Flush with cash, they merged with Lansing Manufacturing to form Altec Lansing. With a large infrastructure and Lansing’s engineering, they became a significant supplier to the military during World War II.

After the war, the company produced a landmark theater speaker system that became the gold standard in theater audio. However, Lansing didn’t like the big company environment and left to found a company that bore his full name, James B. Lansing, which you may know as JBL.

Altec Lansing continued to grow. However, a series of mergers and sales starting in 1969 caused the Altec Lansing company to decline. By the 1990s, Altec Lansing was making cheap PC speakers. A far cry from the gold-standard massive speakers made by the company during its heyday.

We love the history of technology and the people that drove them. Bing Crosby, for example. Or the lesser-known heroes like Edwin Armstrong.

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