Secret weapon for Peace and Quiet

I discovered this secret when my first was a few weeks old.  He was completely inconsolable, as newborns sometimes are.  I was doing all the S's and everything else I could think of to no avail.  Then a song I'd never heard before came on Pandora and within seconds, he was quiet.  With one hand free I hopped on iTunes (2010!) and bought that track before you could say "sweet salve for the ears!"   Behold:

I don't know why it worked but it did, not just my first son but also my second - even now at two and a half.  We keep it at the ready on all devices and we have listened on repeat in the car for many a mile.  It is one of the great wonders of the universe and we will take it.  Try it yourself and see.

One possible theory I've come up with:  it's about 125 bpm.  Perhaps something else they hear in the womb runs at a similar rate?  

Now, I'm not by any means advocating that you soothe your child exclusively with Feist, but in a pinch - when we are both strapped into seats or I've got food cooking on the stove - it's been a valuable trick to have up my sleeve.