Wooden You Like To Hear A CNC-Cut Phonograph Record?

Say what you will about [Thomas Edison], but it’s hard to deny the genius of his self-proclaimed personal favorite invention: the phonograph. Capturing sound as physical patterns on a malleable medium was truly revolutionary, and the basic technology that served as the primary medium of recorded sound for more than a century and built several major industries is still alive and kicking today.

With so much technological history behind it, what’s the aspiring inventor to do when the urge to spin your own phonograph records strikes? Easy — cut them from wood with a CNC router. At least that’s how [alnwlsn] rolled after the “one-percent inspiration” hit him while cutting a PCB with his router. Reasoning that the tracks on the copper were probably about as fine as the groove on a record, he came up with some math to describe a fine-pitch spiral groove and overlay data from a sound file, and turn the whole thing into G-code.

For a suitable medium, he turned to the MDF spoil board used to ship PCB stencils, which after about three hours of milling resulted in a rather hairy-looking 78-RPM record. Surprisingly, the record worked fairly well on a wind-up Victrola. The spring-powered motor was a little weak for the heavy wooden record and needed a manual assist, but you can more or less clearly hear the 40-second recording. Even more surprising was how much better the recording sounded when the steel needle was replaced with a chunk of toothpick. You can check out the whole thing in the video below, and you’ll find the G-code generation scripts over on GitHub.

Is all this talk about reproducing music using wiggly lines confusing you? Woah, there, whippersnapper — check out [Jenny]’s primer for the MP3 generation for the background you need.

Continue reading “Wooden You Like To Hear A CNC-Cut Phonograph Record?”

Piezo Pickup Makes Wax Records Easy To Digitize

Sound recording and playback have come a long way in the last century or so, but it’s fair to say there’s still a lot of interesting stuff locked away on old recordings. Not having a way to play it back is partly to blame; finding an antique phonograph that plays old-timey cylinder recordings is pretty hard. But even then, how do you digitize the output of these fragile, scratchy old recordings?

As it happens, [Jan Derogee] is in a position to answer these questions, with an antique phonograph and a bunch of Edison-style wax cylinders with voices and music from a bygone era locked away on them. It would be easy enough to just use the “reproducer” he previously built and set up a microphone to record the sound directly from the phonograph’s trumpet, but [Jan] decided to engineer a better solution. By adding the piezo element from an electronic greeting card to his reproducer, potted with liberal quantities of epoxy and padded with cotton, the piezo pickup was attached to the phonograph arm in place of the original stylus and trumpet. The signal from the piezo element was strong enough to require a shunt resistor, allowing it to be plugged directly into the audio input jack on a computer. From there it’s just an Audacity exercise, plus dealing with the occasional skipped groove.

We appreciate [Jan]’s effort to preserve these recordings, as well as the chance to hear some voices from the past. We’re actually surprised the recording sound as good as they do after all this time — they must have been well cared for.

Continue reading “Piezo Pickup Makes Wax Records Easy To Digitize”

Reproducing A Reproducer: Servicing A Cylinder Phonograph In The Year 2021

[Jan Derogee] pulled out his phonograph the other day to hear the 100+ year old wax cylinder warble of “It’s a Long Way to Tipperary”, but couldn’t locate the reproducer — this is the small circular bit that holds the stylus and transfers the groove-driven vibrations to the center of a thin diaphragm, which vibrates into the sound horn. It’s easily the most important part of a cylinder phonograph. What do you do when you lose your reproducer? You could search ebay for a replacement, but that wouldn’t be nearly as fun as reproducing your reproducer yourself.

Traditionally, diaphragms were made from mica or celluloid, and the Edison disk phonograph used seven layers of shellac-soaked rice paper. Reproducers typically have a Dagwood sandwich of gaskets surrounding the membrane, but they don’t have to be so convoluted to work — a single strong membrane will do just fine. Just ask [Jan], who made a new reproducer with a 3D-printed case, a hand-pulled glass stylus, and a disposable aluminum foil pan for the diaphragm.

It’s difficult for us to say which part looks more fun — stretching the glass shard over a gas kitchen stove with the flame focused by a stack of wrench sockets, or cutting up a bicycle inner tube and using a car jack to press the aluminum into shape against a 3D-printed mold. The whole video is awesome and you can check it out after the break.

As [Jan] notes in the video and on the project site, the glass stylus should really be made from borosilicate because it’s harder than regular soda lime glass (that’s why they often make vaccine vials out of it). Regular glass will work and takes much less time and gas to reach the pull-able stage, so that’s what [Jan] used in the video, but it will wear out much more quickly. Fortunately, this was a temporary solution, because as soon as [Jan] made a replacement, the missing reproducer showed up.

Continue reading “Reproducing A Reproducer: Servicing A Cylinder Phonograph In The Year 2021”

Tunes You Can Eat

This week retro-gadget collector and video blogger [Techmoan] featured perhaps the most delicious audio recording format that we know of — a chocolate gramophone record. (Video, embedded below.) Compared to his typical media format explorations, the chocolate record is of quite recent vintage. He first heard of them back in 2015 when Tasmanian artist [Julia Drouhin] offered chocolate recordings as part of her art project. The one that [Techmoan] finally obtained was from a UK chocolatier who offers them with custom labelling and your choice of two songs. There are some pointers in the video about how to playback your chocolate disk without ruining it (use the lightest stylus tracking force as possible). These disks are recorded at 45 RPM on one side only, and are about the same size as a standard single. But being about five times thicker, they pack a lot more calories than your typical phonograph disk.

No reflection on the Tewkesbury Town Band, but this is probably the lowest fidelity recording media ever, but at least you can eat it when you’re done listening — label and all. We hope the Mission Impossible movie producers are paying attention so we can see the secret audio briefing being eaten instead of going up in smoke next film.

Continue reading “Tunes You Can Eat”

Talking Clock? That’s Nothing New

Do you talk to your alarm clock? I do. I was recently in a hotel room, woke up in the middle of the night and said, “Computer. What time is it?” Since my Amazon Echo (which responds to the name Computer) was at home, I was greeted with silence. Isn’t the future great?

Of course, there have been a variety of talking clocks over the years. You used to be able to call a phone number and a voice would tell you the time. But how old do you think the talking clock really is? Would you guess that this year is the 140th anniversary of the world’s first talking clock? In fact, it doesn’t just hold the talking clock record. The experimental talking clock Frank Lambert made is also the oldest surviving recording that can be still be played back on its original device.

In 1878, the phonograph had just been invented and scratched out sounds on a piece of tin foil. Lambert realized this wouldn’t hold up to multiple playbacks and set out to find a more robust recording medium. What he ended up building was a clock that would announce the time using lead to record the speech instead of tin foil.

Continue reading “Talking Clock? That’s Nothing New”

Who Made The First Human Audio Recordings? Edison? Not So Fast!

You probably learned in school that Thomas Edison was the first human voice recorded, reciting Mary Had a Little Lamb. As it turns out though, that’s not strictly true. Edison might have been the first person to play his voice back, but he wasn’t the first to deliberately record. That honor goes to a French inventor named Édouard-Léon Scott de Martinville. He wanted to study sound and created the phonautograph — a device which visualized sound on soot-covered paper. They were not made to be played back, but the information is there. These recordings were made around 1860. There’s a 9-part video series about how the recordings were made — and more interestingly — how they were played back using modern technology. Part 1 appears below.

We say around 1860 because there were some early recordings starting around 1857 that haven’t been recovered. Eventually, the recordings would have a tuning fork sound which allows modern playback since the known signal can estimate the speed of the hand-cranked cylinder. The date of the first recovered recording was today, April 9th, 158 years ago.

Continue reading “Who Made The First Human Audio Recordings? Edison? Not So Fast!”

Retrotechtacular: Stereo Records

The 20th century saw some amazing technological developments. We went from airplanes to the moon. We went from slide rules to digital computers. Crank telephones to cell phones. But two of the most amazing feats of that era were ones that non-technical people probably hardly think about. The transformation of radio and TV from mono and black and white, to stereo and color. What was interesting about both of these is that engineers managed to find a way to push the new better result into the same form as the old version and — this is the amazing part — do it in such a way that the old technology still worked. Maybe it is the rate that new technology moves today, but we aren’t doing that today. Digital TV required all-new everything: transmitters, receivers, frequencies, and recording gear. Good luck trying to play the latest video game on your 25-year-old PC.

It is hard to remember when stores were full of all sorts of audio and video media. We’ve noticed that all forms of media are starting to vanish. Everything audio and video are all streamed or downloaded these days. Records, 8-tracks, cassettes, and even CDs and DVDs are vanishing. However, vinyl records have made a come back in the last few years for their novelty or nostalgic value.

Continue reading “Retrotechtacular: Stereo Records”