much has been written of the ticking of a clockwork doll. far less on the ticking heart of the electric doll, be it made of quartz, ceramic, or tantalum.
perhaps because its heart ticks faster than most of us intend to hear. even the slowest dolls tick above the 20KHz to which we bandlimit our acoustic monitors (for legacy reasons mostly, you see). The fastest of them are approaching many gigahertz these days. But you can hear them. If you turn off your ears. If you cut a length of wire to just the right size. They try to hide it with their metal shielding, lest it get in the way of something important, but it's there if you know how to listen.
And how do you listen?
You'll need a tick of your own, of course. One that matches its tick, or close to it, to tune your reception of the signal. Get close and you'll hear a beat-frequency. Not your beat, not its beat, but a synthesis of the two. The interference pattern of your signals, vibrating at a speed matching the difference between them. Match its tick closer and listen to the beat slow into a comfortable rhythm. You two are not the same, but now you're very very similar.
But something magical happens when it listens back to you, drifting its tick towards yours as yours drift towards its. Coupling. Your oscillations matching each other perfectly. And in this state, truly, neither of you can be said to have your own tick. Together you create and share a single pulse, your phases locked together.