Why is this interesting - The Hidden Noise Edition

On hidden tracks, vinyl, and hacking algorithm culture

Todd Osborn (TO) is a candidate for WITI’s most interesting man in the world award. He was an Air Force Airman based in Okinawa, speaks Japanese, and is an in-demand DJ and producer (check his superb track Hold Up, here, dub remixed by Hot Chip’s Joe Goddard). He’s also a rare bourbon connaisseur, fixes and flies planes, has fabricated a video game kiosk out of hospital equipment, and owns an actual hovercraft. Check the store he runs with his son, Technical Equipment Supply—which will soon be the exclusive supplier of the elusive and much coveted WITI totes (!). This is longer than we usually publish but we think you’ll love it. - Colin (CJN) 

Todd here. I've always loved the "bonus track." An extra tune on an LP—it might be an alternate remix, maybe only found if you let the silence of the last track play out, or possibly even hidden before the first track on the CD (play track 1 and hold reverse to rewind into an unlisted tune)!

Around 2003, I was getting deep into the process of how records are made with my friend Ron Murphy who ran National Sound Corporation. (Ron, a legend in the Detroit music community, sadly passed away in 2008.) Briefly, the master recording is transferred ("cut") via lathe onto an acetate covered metal disc. That disc is coated in a nickel-plating and when that plating is removed you now have molds to stamp your records out of hot vinyl.

Ron was great at creative thinking and he came up with interesting new ways to cut records—continuous closed-looped grooves, tracks that play inside to out, two tracks cut side by side (parallel spirals) that look like one, etc. Ron's first foray into record cutting was a small plastic toy that cut into plastic and badly recorded your voice. This led to us talking about alternate methods to make and copy records. I had been working on replicating motorcycle parts using high tensile plastic resins for detailed molds and thought they might be able to handle the detail of record grooves. I made a few prototypes and honed the process well enough that the loudness level was nearly as high as the original and seemed to last many, many plays without degradation of sound because these resins were much stronger than vinyl. I could only mold one side at a time and the first examples looked like peanut brittle on the flip side from all the air bubbles. 

As I refined the process, I realized I could make these single sides extremely thin and still hold up (and not waste resin). I figured if I made them half the thickness of a record and then fused the two single sides into one I would have basically replicated a 12". But looking at these thin halves got me thinking: what if I put a 7" flexi disc (the kind you used to get as magazine inserts years ago) in between these two sides before fusing them? It would be interesting to mold two awful tracks but then have a flexi disc inside with two amazing tracks. My hope was that after selling a few of these, someone would hate the record so much that they would smash it, and lo and behold, they were rewarded with two secret tunes! 

Before I got around to all of that, the fact I was getting the resin so thin yet strong gave me another idea. I had Ron cut an acetate of a tune where the label on a record normally is. Then, when I made my mold, I used the thinnest layer of resin I could get away with and laid the printable side of a CD-R in it as it was drying. So now I had a normal looking CD. Still thin enough to be played in a car stereo but had one secret analog recording on top that could be played on a record player. These ideas ultimately didn't go anywhere outside of prototypes.

Skipping ahead to early 2009, I had a friend who was perturbed that he had given out advance MP3's to a few select people for personal enjoyment and yet they showed up on music sharing sites. I wondered if there was a way to make these traceable back to the source of the leak. I ran across a little program called MP3nema that lets you hide and extract hidden files in mp3s, tucked away between frames. You could add images, PDFs, and the like, though they needed to be pretty small (a 3 min 128k MP3 that is 30MB would be suspicious). So I was thinking about making a text file with the person’s name and hiding it in the frames—like personalizing it for them. They can still mess with the MP3 metadata and the file will stay hidden unless they totally re-encode the MP3. If I see the track floating around online, I can extract the txt file and see where it originated. This was also useful to just trace the path of your files.

For instance: post an MP3 that has a file hidden with the name of the site on a few social sites that has a file hidden with the name of the site  A few months later go on Soulseek and download your tracks and see which source had the most exposure. But to get back to the hidden track theme, the main idea I had was that instead of text or a picture, why not hide an MP3 within an MP3? Nowadays you could distribute this via Bandcamp and wait quite a long time, then announce that there is a whole other tune that can be extracted.

Why is this interesting?

With all this hidden track talk, I recently ended up in a situation where I could hide a track in a track ... but it isn't actually even there. Sounds confusing, I know.

In 2020, tracing a track to see who's playing them isn't such a novel idea. Content ID algorithms will tell what coffee shop a tune is being played at, who searched for it, and who should be paid royalties. This is the protocol that flags Youtube videos if someone has uploaded copyrighted content, and also how programs like Shazam identify the song you are listening to. Years ago you could do simple tricks to circumvent this system, but they've kept advancing the algorithm and I haven't found any evidence of people being able to reliably fool it since 2013. 

A quick summary of how it works: it takes a middle area of 16 frequency bands of the musical spectrum (it's using the middle part mainly to account for bad speaker systems where high and low frequencies are the first to disappear) and then records energy points within these bands and connects the dots—pretty analogous to matching a unique pattern of points on a human fingerprint. I casually DJ at a friend's bar every week in a very laid-back situation and I often see people trying to Shazam songs and I was wondering if I could affect these files so that they don't show up. Through much trial and error, I figured out a couple of ways to fool the system (see if this returns any results). I'd rather not say exactly how it's done, because it could cause some trouble and this post would be much too long, but as I was doing these spectral band experiments, I found you could have two or three narrow bands that were barely audible but still contained enough points to ID the track. Once I figured out how to make the results of a popular track come up blank, I could then overlay these easily-ID'd-but-barely-audible spectral bands on the base track so that the results would come back as a positive hit of the hidden spectral information. So, in theory, I could upload this file of Mary Jane Girls "In My House" and Youtube's software will ID it as my track Osborne "Wait a Minute" and I'd collect royalties on the number of plays until someone happens to notice. Since this ID process is left up to software, it could take a while before anyone caught on. (TO)

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Thanks for reading,

Noah (NRB) & Colin (CJN) & Todd (TO)

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