When Janet Jackson sang, “With music by our side, we’ll break the color lines,” not even she could have known she was talking about the Microsoft logo. But as it turns out, the overpowering rhythm of “Rhythm Nation” — or at least, the vibrational resonance of that beat — kept causing certain models of Microsoft laptops to crash.
The bizarre tale of music-as-cyberthreat was shared by Microsoft chief software engineer Raymond Chen last week, and subsequently picked up by The Next Web. According to Chen, “The song contained one of the natural resonant frequencies for the model of 5400 rpm laptop hard drives that [Microsoft] and other manufacturers used.”
For those who haven’t seen the inside of a physics classroom recently, the resonant frequency is the natural frequency where a medium vibrates at the highest amplitude. You know how sound can shatter glass at a certain pitch? That’s because that pitch causes the glass molecules to vibrate the most.
The phenomena is more common than you might think, and the results have ranged from weird to deadly. In 1940 the Tacoma Narrows Suspension Bridge collapsed after winds caused the bridge to vibrate at its natural frequency. The bridge had survived higher-speed winds, but sustained gusts at about 40-miles-per-hour caused the oscillations to enter a positive feedback loop, so that the vibrations got bigger and bigger until they tore the bridge apart.
More recently, in 2011 a 17-person fitness class in South Korea forced a building to shake for 10 minutes, making residents flee in panic. Many initially blamed a small earthquake, but a professor and a group of 17 middle-aged volunteers were able to prove that the tremors were caused by a Tae Bo class dancing to “The Power” by SNAP!, which caused the high-rise to vibrate at its resonant frequency.
As Microsoft’s Chen explained, something similar was happening with 5400 rpm laptops exposed to “Rhythm Nation.” The phenomena didn’t even require the laptop to be playing the song; just pipe it through speakers, and nearby laptops would rattle and shut down.
Chen wrote, “The manufacturer worked around the problem by adding a custom filter in the audio pipeline that detected and removed the offending frequencies during audio playback.” He added that because the patch had been applied several years ago, he wouldn’t be surprised if it was still around on some models because “nobody remembers why it’s there. Hopefully, their laptops are not still carrying this audio filter to protect against damage to a model of hard drive they are no longer using.”
Is your laptop susceptible? Almost certainly not, but you should probably blast “Rhythm Nation” by Janet Jackson just to make sure. Check it out below.