Per 
Item #: SCP-XXXX
Object Class: Euclid
Special Containment Procedures: SCP-XXXX is to be kept in an anechoic chamber, lined with the standard soundproofing required for such a room. Access is restricted to level 3 personnel. Any personnel requiring entry must wear noise-cancelling headphones and listen to music (of their choice) with a strong beat from before entering to after leaving the chamber and must not remove the headphones or pause their music at any point while inside the chamber.
Description: SCP-XXXX is a metronome of classic clockwork design, with a swinging weighted arm and wind-up handle. The metronome appears and acts fully mundane until a tempo is selected and the arm is set in motion. When the metronome begins to tick, any organisms that are capable of hearing or otherwise perceiving the sound will begin to move in time. This effect is not limited to simply bodily movements, however, as tests have shown that even structures as small as subatomic particles within affected subjects' bodies will vibrate, move, or perform their function in time, albeit in a 1/n subdivision more befitting of their scale, with a larger n value being a faster vibration. For example, human hearts maybe begin to beat in time with the metronome if it is set to a high enough tempo, or beat in a 1/2 or 1/3 subdivision if the set tempo is quite slow. This anomalous effect has been observed to lead to a variety of end results in exposed subjects (detailed in Addendum XXXX-B) ranging from minor inconvenience to near near immediate expiry.
