We were sitting around a table at The Barley Street Tavern waiting for the band to get its shit together when the discussion turned to the weird bleep-bloop sounds recorded at the end of pre-recorded cassette tapes.
“I think those are some sort of signal to tell you it’s time to turn the tape over,” said the guy sitting with us, a music legend (of sorts). But I knew he couldn’t be right. The noise that tells you it’s time to turn the tape over is the low whine of the motor followed by a loud “Thuck!” of the tape deck clicking off. And besides, just about every tape deck made after 1980 was auto-reverse. Were tape makers trying to tell us that the motors were about to go in reverse and play Side B? Come on…
It just dawned on me that you younger folks are scratching your heads wondering what the hell I’m talking about. What sound on the end of the cassette tape? And what’s a cassette tape?
The sound is a series of electronic tones from low to high each lasting a split second, strung together like a ladder of noise, like a sonic rainbow. The tape manufacturers didn’t start putting it on tapes until later in the life cycle of cassette tape technology, and only for a brief sliver of that technology’s history.
The tones recently made a cameo appearance in modern times. Arcade Fire includes them as an ironic statement about technology on their new album Refecktor at the end of track 7, “Joan Of Arc,” which also happens to be the end of the first CD in the double-disc package (but you wouldn’t know that if you were listening on Spotify).
I always thought the bleep-bloop sound was an audio check, kind of like a TV test pattern for your hi-fi system or car stereo, but what standard was it supposed to be checking against? Or maybe it was an early version of an audio product logo, like the rousing orchestral tone you hear when you fire up your Apple computer, a congratulations heard every time you turn on your MacBook that you wisely chose an Apple product over a Windows PC.
Still, our friend insisted it was intended to tell you to turn your cassette over, like those old children’s books that came with a 45 rpm record that had a recorded tone to tell you when to turn the page.
When I got home later that night I turned to Google for answers and typed in the phrase “weird audio tones at the end of cassettes.” The first thing returned in the search engine was a link to the Wikipedia entry for “XDR (audio).”
According to the anonymous author who wrote the entry, “XDR (eXtended Dynamic Range, also known as SDR (Super Dynamic Range)) is a quality control and duplication process for the mass production of pre-recorded audio cassettes.” XDR boasted a higher dynamic range, “up to 13 decibels greater.”
It didn’t matter that the typical factory-fresh DELCO cassette deck that came pre-mounted in your brand new 1978 Ford Fiesta couldn’t reproduce that range with its 4-inch paper-cone dash-mount speakers, or that even if they could you wouldn’t be able to hear it over the traffic noise or the annoying person sitting next to you.
The Wiki entry went on about tape duplication processes and how EMI / Capitol Records and PolyGram were among the labels that fell for the XDR hustle. It wasn’t until later in the entry that it got to the part about the bleep-bloop noises.
The XDR process included “recording a short test tone burst at the beginning and end of the program material on the cassette, to detect for any loss of audio frequencies in the audio spectrum. The tone burst consists of 11 tones about 0.127 seconds in length (with 0.02 seconds of silence in between each tone), from 32 to 18,000 Hz.”
The entry doesn’t include any dates. The first time (I think) I heard them was on my brother’s Duran Duran Rio cassette, which came out in 1982, or maybe it was his Red Rider Neruda cassette, released in 1983. It couldn’t have been much later than that because I remember buying my first compact disc, The Fixx’s Shuttered Room, at Kmart in 1982. Before long, CDs would be the only format that I or anyone else would buy, and cassettes, along with vinyl, would become relics of the past like the 8 Track tape.
So there it is.
If you go to YouTube and search for “Cassette Tones,” you’ll find a 13-second video that reproduces the bu-bu-bu-bu-bleep! noise in all its hissing glory. For those of us who lived through that era it’s like an audio lighthouse from a kinder, gentler time, before computers and the internet and iPods and smart phones, when “high fidelity” meant gigantic, ugly home stereo systems, ridiculous car stereos with 6 x 9 speakers and twinkling-light equalizers, and cassettes that ended with a rainbow of sound.
Over The Edge is a weekly column by Reader senior contributing writer Tim McMahan focused on culture, society, the media and the arts. Email Tim at email@example.com.