Measuring A Well With Just A Hammer And A Smartphone

December 19, 2024 by Dan Maloney 31 Comments

What’s the best way to measure the depth of a well using a smartphone? If you’re fed up with social media, you might kill two birds with one stone and drop the thing down the well and listen for the splash. But if you’re looking for a less intrusive — not to mention less expensive — method, you could also use your phone to get the depth acoustically.

This is a quick hack that [Practical Engineering Solutions] came up with to measure the distance to the surface of the water in a residential well, which we were skeptical would work with any precision due to its deceptive simplicity. All you need to do is start a sound recorder app and place the phone on the well cover. A few taps on the casing of the well with a hammer send sound impulses down the well; the reflections from the water show up in the recording, which can be analyzed in Audacity or some similar sound editing program. From there it’s easy to measure how long it took for the echo to return and calculate the distance to the water. In the video below, he was able to get within 3% of the physically measured depth — pretty impressive.

Of course, a few caveats apply. It’s important to use a dead-blow hammer to avoid ringing the steel well casing, which would muddle the return signal. You also might want to physically couple the phone to the well cap so it doesn’t bounce around too much; in the video it’s suggested a few bags filled with sand as ballast could be used to keep the phone in place. You also might get unwanted reflections from down-hole equipment such as the drop pipe or wires leading to the submersible pump.

Sources of error aside, this is a clever idea for a quick measurement that has the benefit of not needing to open the well. It’s also another clever use of Audacity to use sound to see the world around us in a different way.

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Recreating The Quadrophonic Sound Of The 70s

February 6, 2024 by Bryan Cockfield 23 Comments

For plenty of media center PCs, home theaters, and people with a simple TV and a decent audio system, the standard speaker setup now is 5.1 surround sound. Left and right speakers in the front and back, with a center speaker and a subwoofer. But the 5.1 setup wasn’t always the standard (and still isn’t the only standard); after stereo was adopted mid-century, audio engineers wanted more than just two channels and briefly attempted a four-channel system called quadrophonic sound. There’s still some media from the 70s that can be found that is built for this system, such as [Alan]’s collection of 8-track tapes. These tapes are getting along in years, so he built a quadrophonic 8-track replica to keep the experience alive.

The first thing needed for a replica system like this is digital quadrophonic audio files themselves. Since the format died in the late 70s, there’s not a lot available in modern times so [Alan] has a dedicated 8-track player connected to a four-channel audio-to-USB device to digitize his own collection of quadrophonic 8-track tapes. This process is destructive for the decades-old tapes so it is very much necessary.

With the audio files captured, he now needs something to play them back with. A Raspberry Pi is put to the task, but it needs a special sound card in order to play back the four channels simultaneously. To preserve the feel of an antique 8-track player he’s cannibalized parts from three broken players to keep the cassette loading mechanism and track indicator display along with four VU meters for each of the channels. A QR code reader inside the device reads a QR code on the replica 8-track cassettes when they are inserted which prompts the Pi to play the correct audio file, and a series of buttons along with a screen on the front can be used to fast forward, rewind and pause. A solenoid inside the device preserves the “clunk” sound typical of real 8-track players.

As a replica, this player goes to great lengths to preserve the essence of not only the 8-track era, but the brief quadrophonic frenzy of the early and mid 70s. There’s not a lot of activity around quadrophonic sound anymore, but 8-tracks are popular targets for builds and restorations, and a few that go beyond audio including this project that uses one for computer memory instead.

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Audacity Runs Surprisingly Well In Your Browser

October 5, 2023 by Tom Nardi 13 Comments

Audacity is an extremely popular open source audio editor, with hundreds of millions of downloads on the books. But due to some controversy over changes the Muse Group wanted to implement when they took ownership of the project back in 2021, the userbase has fractured somewhat. Some users simply stick with an older version of the program, while others have switched over to one of the forks that have popped up in the last couple of years.

The Wavacity project by [Adam Hilss] is a bit of both. It looks and feels just like an older version of Audacity (specifically, 3.0.0). But the trick here is that he’s managed to get it working with WebAssembly (WASM) so you can run it in your browser. Impressively, it even works on mobile devices. Though the Audacity UI, which already carries the sort of baggage you’d expect from a program that’s more than 20 years old, is hardly suited to a touch screen. Continue reading “Audacity Runs Surprisingly Well In Your Browser” →

Persistence Pays In TI-99/4A Cassette Tape Data Recovery

June 16, 2023 by Dan Maloney 11 Comments

In the three or four decades since storing programs on audio cassettes has been relevant, a lot of irreplaceable personal computing history has been lost to the ravages of time and the sub-optimal conditions in the attics and basements where tapes have been stored. Luckily, over that time we’ve developed a lot of tools and techniques that might make it possible to recover some of these ancient treasures. But as [Noel] shows us, recovering data from cassette tapes is a tricky business.

His case study for the video below is a tape from a TI-99/4A that won’t load. A quick look in Audacity at the audio waveform seems to show the problem — an area of severely attenuated signal. Unfortunately, no amount of boosting and filtering did the trick, so [Noel] had to dig a bit deeper. It turns out that the TI tape interface standard, with its redundant data structure, was somewhat to blame for the inability to read this particular tape. As [Noel] explains, each 64-bit data record is recorded to tape twice, along with a header and a checksum. If neither record decodes correctly, then tape playback just stops.

Luckily, someone who had already run into this problem spun up a Windows program to help. CS1er — our guess would be “Ceaser” — takes WAV file input and loads each record, simply flagging the bad ones instead of just bailing out. [Noel] used the program to analyze multiple recordings of the same data and eventually got enough good records to reassemble the original program, a game called Dogfight — or was it Gogfight? Either way, he managed to get most of the data off the tape, and since it was a BASIC program, it was pretty easy to figure out the missing bytes by inspection.

[Noel]’s experience will no doubt be music to the ears of the TI aficionados out there. Of which we’ve seen plenty, from the TI-99 demoscene to running Java on one, and whatever this magnificent thing is.

Continue reading “Persistence Pays In TI-99/4A Cassette Tape Data Recovery” →

New Privacy Policy Gets Audacity Back On Track

July 23, 2021 by Tom Nardi 29 Comments

Regular readers will likely be aware of the considerable debate over changes being made to the free and open source audio editor Audacity by the project’s new owners, Muse Group. The company says their goal is to modernize the 20 year old GPLv2 program and bring it to a larger audience, but many in the community have questioned whether the new managers really understand the free software ethos. An already precarious situation has only been made worse by a series of PR blunders Muse Group has made over the last several months.

But for a change, it seems things might be moving in the right direction. In a recent post to Audacity’s GitHub repository, Muse Group unveiled the revised version of their much maligned Privacy Policy. The announcement also came with an admission that many of the key elements from the draft version of the Privacy Policy were poorly worded and confusing. It seems much of the problem can be attributed to an over-analysis of the situation; with the company inserting provocative boilerplate protections (such as a clause saying users must be over the age of 13) that simply weren’t necessary.

Ultimately, the new Privacy Policy bears little resemblance to the earlier draft. Which objectively, is a good thing. But it’s still difficult to understand why Muse Group publicly posted such a poorly constructed version of the document in the first place. Project lead Martin Keary, better known online as Tantacrul, says the team had to consult with various legal teams before they could release the revised policy. That sounds reasonable enough, but why where these same teams not consulted before releasing such a spectacularly ill-conceived draft?

The new Privacy Policy makes it clear that Audacity won’t be collecting any user data, and what little personally identifiable information Muse Group gets from the application when it automatically checks for an update (namely, the client’s IP address) isn’t being stored. It’s further explained in the GitHub post that the automatic update feature only applies to official binary builds of Audacity, meaning it will be disabled for Linux users who install it through their distribution’s package repository. The clause about working with unnamed law enforcement agencies has been deleted, as has the particularly troubling age requirement.

Credit where credit is due. Muse Group promised to revise their plans for adding telemetry to Audacity, and judging by the new Privacy Policy, it seems they’ve done an admirable job of addressing all of the issues brought up by the community. Those worried their FOSS audio editor of choice would start spying on them can rest easy. Unfortunately the issue of Audacity’s inflammatory Contributor License Agreement (CLA) has yet to be resolved, meaning recently christened forks of the audio editor dedicated to preserving its GPLv2 lineage are unlikely to stand down anytime soon.

Open Source Is Choice

July 17, 2021 by Elliot Williams 79 Comments

If you haven’t been following along with the licensing kerfuffle surrounding the open-source Audacity audio editing software, take a sec to read Tom Nardi’s piece and get up to speed. The short version is that a for-profit company has bought the trademark and the software, has announced plans to introduce telemetry where there was none, made ominous changes to the privacy policy that preclude people under the age of consent from using the software, and requested that all previous developers acquiesce to a change in the open-source license under which it is published. All the while, the company, Muse, says that it will keep the software open, and has walked back and forth on the telemetry issue.

What will happen to “Audacity”? Who knows. But also, who cares? At least one fork of the codebase has been made, with the telemetry removed and the old open licenses in place. The nicest thing about open source is that I don’t care one bit if my software is named Audacity or Tenacity, and this is software I use every week for production of our podcast. But because I haven’t paid any license fees, it costs me absolutely nothing to download the same software, minus some anti-features, under a different name. If the development community moves over to Tenacity, it’ll all be fine.

Tom thinks that the Audacity brand is too big to fail, and that Muse will have a hit on their hands. Especially if they start implementing new, must-have features, they could justify whatever plans they have in store, even if they’re only available as a “freemium” Audacity Pro, with telemetry, under a more restrictive license. When that does happen, I’ll have to make the choice between those features and the costs, but I won’t be left out in the cold as long as the Tenacity fork gets enough eyes on it. So that’s just more choice for the end-user, right? That’s cool.

Compare this with closed source software. There, when the owner makes an unpopular decision, you simply have to take it or make the leap to an entirely different software package. This can be costly if you’ve gotten good at using that software, and between licenses and learning, there’s a lot of disincentive to switching. Not so in this case. If I don’t want to be tracked while editing audio offline, I don’t have to be. Woot.

The elephant in the room is of course the development and debugging community, and it’s way too early to be making predictions there. However, the same rules apply for devs and users: switching between two virtually identical codebases is as easy as git remote add origin or apt get install tenacity. (Unpaid) developers are free to choose among forks because they like the terms and conditions, because one group of people is more pleasant to work with, or because they like the color of one logo more than the other. Users are just as free to choose.

Time will tell if Audacity ends up like the zombie OpenOffice, which is downloaded in spite of the much superior LibreOffice just because of the former’s name recognition. I know this split riles some people up, especially in the LibreOffice development community, and it does seem unfair that the better software somehow enjoys less reputation. But for those of us in the know, it’s just more choice. And that’s good, right?

Just What Have We Become?

July 16, 2021 by Jenny List 69 Comments

The world of open source software is one that often sees disputes between developers, some of which spawn lifelong schisms between devotees of different forks, and others mere storms in a teacup that are settled over a few beers. There are a couple of stories of late though that seem to show the worst in the online world, and which all of us should take a moment to think about.

Many of you may have heard two weeks ago of the passing of [near], the software developer and game translator whose bsnes emulator for the Super Nintendo was the go-to platform for retro Nintendo enthusiasts intent on the pursuit of the closest possible match to the original without possessing real Nintendo hardware. The details of their passing are particularly distressing, in that they committed suicide after numerous attacks over several years from users of Kiwi Farms, a website notorious for the worst kinds of trolling.

Hot on the heels of that distressing story comes news that [Cookie Engineer] is stepping down as maintainer of the project that’s now called Tenacity, a fork of the popular but now-controversial Audacity audio editor. They are doing so after being targeted by users of 4chan, the most well-known of online trolling websites, following an ill-advised Simpsons joke in a naming poll for the software. [Cookie Engineer] alleges that the harassers knocked on doors and windows where they live and a real-world knife attack followed.

Nobody deserves to be hounded to death, to suffer the sort of sustained harassment that [near] encountered, or to be confronted with knife-wielding strangers merely because they have stuck their head above the parapet as an open-source developer. There are no excuses to be made, no justifications for this.

All of us who read Hackaday are likely to be regular users of open-source software, many of us will have used bsnes and may yet use Tenacity, but we probably rarely stop for a moment to think of the real people behind them. Countless hours from innumerable highly-skilled people are what makes the open-source world tick, and aside from the immeasurable sadness of suicide or the horror of a knife attack there can only be harm done to open source software as a whole if to be a prominent developer or maintainer is to expose yourself to this.

The Internet will always have raucous communities at its margins and that’s something which still contributes to its unique culture, but when it jumps off the webpage and into damaging real people then perhaps it has become a monster. As a community we can do so much better, and we shouldn’t be prepared to accept anybody who thinks otherwise among our ranks.

We’d like to remind our readers that help exists for those who have reached the point of considering suicide, and that should you suffer from mental health problems you are not alone in this. Everybody, take care of yourselves, and keep an eye out for each other.