Ray's panels on the wall - circles of different sizes (from 60 to 15cm in diameter) covered by fabric of different shades, their arrangement vaguely resembling a cloud.

DIY Acoustic Panels Or Modern Artwork? Can’t Tell

January 31, 2022 by Arya Voronova 25 Comments

The acoustic properties of a room have a surprising impact when you want to use a microphone. [RayP24]’s son was trying to make his bedroom into a better recording studio, and for [Ray], that turned into an artfully-executed wall panel project. Fortunately, the process is documented so we all can learn from it. When it comes to acoustics, you can often get a whole lot of improvement from surprisingly few changes. And, as this project demonstrates, you can make it look like a decorative piece to boot.

When arranged and placed on the wall, these panels look like an art piece, a decoration you could get from a somewhat fancy store. If you show them to someone, they might not believe that they also serve as a functioning home acoustics improvement, dampening the sound quite well for audio recording needs. The panels are built out of individual circles, cut out in a way that uses as much of a 3/16″ (5mm) plywood sheet as possible, with hollow circles serving as frames to attach foam-backed fabric. In the Instructables post, [Ray] talks quite a bit about how you can assemble your own and what liberties you can take. There’s also a short video accompanying this project, which you can see after the break. This project is begging to be recreated.

There’s a sizeable amount of hacking-meets-home improvement-meets-home acoustics projects out there, especially lately, when so many people are stuck at home for one reason or another. Just a few months ago, we covered another marvelous “art piece turned reverb killer” project operating by a slightly different principle, and also going a bit more into the theory. Perhaps in a few years, we will no longer have to build panels or structures for our soundproofing needs, as purpose-grown mycelium shapes will do that for us. And once it becomes a question of where to hang your newly-built acoustic panels, this simple guide is a good place to start.

Continue reading “DIY Acoustic Panels Or Modern Artwork? Can’t Tell” →

Adding WiFi Remote Control To Home Electronics? Be Prepared To Troubleshoot

January 19, 2022 by Donald Papp 32 Comments

[Alex] recently gave a Marantz audio amplifier the ability to be remotely-controlled via WiFi by interfacing an ESP32 board to a handy port, but the process highlights how interfacing to existing hardware often runs into little, unforeseeable problems that can sink the project unless solved.

At its core, the project uses an ESP32 and the ESPAsyncWebServer project to create a handy web interface that is accessible over WiFi. Then, to actually control the amplifier, [Alex] decoded the IR-based remote signals by watching the unit’s REMOTE ports, which are intended as a pass-through and repeater for IR signals to other Marantz units. This functionality can be exploited; by sending the right signals to the REMOTE IN port, the unit can be controlled by the ESP32. With the ESP32 itself accessible by just about any WiFi device, [Alex] gains the freedom to control his amplifier with much greater flexibility than just the IR remote would offer.

Sounds fairly straightforward, but as usual when interfacing to an existing piece of electronics, there were a few glitches. The first was that high and inconsistent latency (from 10 ms to 100 ms) made controlling the amplifier a sometimes frustrating experience, but that was solved by disabling power saving on the WiFi interface. Another issue was that sending signals by connecting a GPIO pin to the REMOTE IN port of the amplifier worked, but had the side effect of causing the amplifier to no longer listen to the IR remote. Apparently, current flowing from the REMOTE port to the ESP32’s GPIO pin was to blame, because adding a diode in between fixed the problem.

The GitHub repository holds the design files and code. This kind of project can be pretty complex, because the existing hardware doesn’t always play nice, and useful boards like a modern ESP32 aren’t always available. Adding a wireless interface to vintage audio equipment has in the past involved etching circuit boards and considerably more parts.

CEEFAX Lives! (Courtesy Of A Raspberry Pi)

January 7, 2022 by Jenny List 28 Comments

As analogue TV slides from memory, there’s a facet of it that’s fondly remembered by a band of enthusiasts. Teletext was an electronic viewdata information service digitally encoded in the frame blanking period, and a TV set with a decoder chip would provide access to many pages of news and other services all displayed in the characteristic brightly colored block graphics. It went the way of the dinosaur with the demise of analog TV, but for [Nathan Dane] the flame is kept alive with his own private version of the BBC’s CEEFAX service.

He has a particular enthusiasm for analog TV, and as such has his own in-house channel served by a UHF modulator. He shares with us the story of how he arrived at a teletext service, before writing code to scrape the BBC news and weather websites and populate his modern-day CEEFAX. Behind it all is a Raspberry Pi, with a vbit-pi board injecting the teletext signal onto the video, and raspi-teletext creating the pages from source material derived from a set of custom scraper scripts.

We like this project a lot, because while it’s not the first Pi teletext system we’ve encountered, the use of a scraped live feed makes it one of the most creative.

Thanks [kwikius] for the tip!

The Label Says HDMI 2.1 But That Doesn’t Mean You’ll Get It

December 27, 2021 by Lewin Day 48 Comments

Technology moves quickly these days as consumers continue to demand more data and more pixels. We see regular updates to standards for USB and RAM continually coming down the pipeline as the quest for greater performance goes on.

HDMI 2.1 is the latest version of the popular audio-visual interface, and promises a raft of new features and greater performance than preceding versions of the standard. As it turns out, though, buying a new monitor or TV with an HDMI 2.1 logo on the box doesn’t mean you’ll get any of those new features, as discovered by TFT Central.

Continue reading “The Label Says HDMI 2.1 But That Doesn’t Mean You’ll Get It” →

Know Audio: Mixtapes, Tape Loops, And Razor Blades

December 20, 2021 by Jenny List 16 Comments

In our no-nonsense journey through the world of audio technology we’ve so far have looked at digital audio and the vinyl disk recording. What’s missing? Magnetic tape, the once-ubiquitous recording medium that first revolutionised the broadcast and recording industries in the mid-20th-century, and went on to be a mainstay of home audio before spawning the entire field of personal audio. Unless you’re an enthusiast or collector, it’s likely you won’t have a tape deck in your audio setup here in 2021 and you’ll probably be loading your 8-bit games from SD card rather than cassette, but surprisingly there are still plenty of audio cassettes released as novelties or ephemeral collectables.

The Device That Made The Sound Of The Latter Half Of The 20th Century

"Like a travelling razor blade", a Blattnerphone steel-strip tape recorder at the BBC in 1937. Douglas Hallam, Jr., Public domain. — “Like a travelling razor blade”, a Blattnerphone steel-strip tape recorder at the BBC in 1937. Douglas Hallam, Jr., Public domain.

The first magnetic recordings were made directly on metal wires, but metal fatigues as it bends. By coating a flexible plastic tape in ferrous particles, the same simple technique of laying down an audio signal as variations in the magnetic field could be made smaller, lighter, and more robust. But the key to the format’s runaway success is the technical advancements that differentiate those 1950s machines from their wire recorder ancestors.

Whether it is a humble cassette recorder or a top-end studio multitrack, all tape recorders are very similar. There are two reels that hold the tape: the playback reel that houses the recording, and the take-up reel that stores the tape as it plays in the machine. The take-up reel is lightly driven to run faster than the tape speed, and the playback reel has a slight braking force to keep the tape under tension at all times. Continue reading “Know Audio: Mixtapes, Tape Loops, And Razor Blades” →

Wii Meets Its End In Breadcrumb Jail

December 15, 2021 by Arya Voronova 9 Comments

One of often encountered traits of a hacker is an ability to build devices into places where they don’t belong. Perhaps, [sonictimm]’s self-descriptive WiiinToaster was somewhat of an inevitability. Inspired by the legendary Nintoaster project which used a NES, this is a modern take on the concept, putting a Wii inside what used to be an ordinary bread-making kitchen appliance. [Sonictimm] has taken care to make it as functional while reusing the user interface options commonly found in a toaster, with some of the Wii’s connections routed to the original buttons and the lever. It’s compatible with everything that the Wii supports in its standard, non-toaster form – the only function that had to be sacrificed was the “making toast” part of it, but some would argue it’d be a bit counterproductive to leave in.

[Sonictimm] says it took five years from building the WiiinToaster to documenting it, which sounds about right for an average project. If you, like many, have a Wii laying around that you haven’t been using for years, building it into a toaster (or any other place a Wii shouldn’t be) is a decent weekend project. Perhaps, a spacier chassis will also help with the overheating problems plaguing some earlier Wii models. One thing we would not recommend, however, is building a toaster into a Wii case – unless you like to see your creations self-immolate, in which case, make sure to film it and grace our Tips line with a YouTube link. There’s also a challenge for the achievement-minded hackers out there – making a rebuild so daring, it gets a DMCA notice from Nintendo.

It wouldn’t be the first time we feature a Nintendo console reborn in a toaster’s shell, with NES and SNES projects coming to mind. If you’re interested in other directions of Wii rebuilds, perhaps you could make an Altoids-sized FrankenWii, or an unholy hybrid of three consoles. And if you do build a Switchster, or a ToaDSter (perhaps, best suited for a waffle iron), we’d love to take a look!

Continue reading “Wii Meets Its End In Breadcrumb Jail” →

The Seductive Pull Of An Obsolete Home Movie Format

December 15, 2021 by Jenny List 53 Comments

It’s dangerous for a hardware hacker to go into a second-hand store. I was looking for a bed frame for my new apartment, but of course I spent an age browsing all the other ~~rubbish~~ treasures on offer. I have a rough rule of thumb: if it’s not under a tenner and fits in one hand, then it has to be exceptional for me to buy it, so I passed up on a nice Grundig reel-to-reel from the 1960s and instead came away with a folding Palm Pilot keyboard and a Fuji 8mm home movie camera after I’d arranged delivery for the bed. On those two I’d spent little more than a fiver, so I’m good. The keyboard is a serial device that’s a project for a rainy day, but the camera is something else. I’ve been keeping an eye out for one to use for a Raspberry Pi camera conversion, and this one seemed ideal. But once I examined it more closely, I was drawn into an unexpected train of research that shed some light on what must of been real objects of desire for my parents generation.

A Thrift Store Find Opens A Whole New Field

One f the surprises comes in just how small this thing is. — One of the surprises comes in just how small this thing is.

The Fuji P300 from 1972 is typical among consumer movie cameras of the day. It takes the form of a film magazine with a zoom lens assembly on its front, a reflex viewfinder on its side, and a handle with a shutter trigger button on it protruding vertically below the magazine and also housing the batteries.

Surprisingly it still has a mercury cell that would have powered its light meter; a minor annoyance to dispose of this correctly. Sometimes these devices had clockwork motors, but this one has an electric motor. It also has a light sensor that is coupled to some kind of electromechanical aperture. It would have been an expensive camera when it was new, probably as much of a purchase as an SLR or a decent mirrorless camera here in 2021.

The surprise came when I opened it up, for it looked like no other 8mm camera I had seen. I’m familiar wit the two reels of a Standard 8 or the boxy cassette of Super 8, but this one used something different. That film magazine is made to fit a compact twin-reel cartridge whose film fits in a metal film gate. This is a Single 8 camera, Fuji’s entry in the all-in-one 8 mm film market, and a format I never knew existed. To explain my unexpected discovery it was necessary to delve into the world of home movie formats in the decade before videotape arrived and drove them out. Continue reading “The Seductive Pull Of An Obsolete Home Movie Format” →