Methods and apparatus for unsupervised wakeup of a device including receiving a first acoustic event at a first time and a second acoustic event at a second time, wherein scores of the first and second acoustic events are above a first threshold identifying the first and second acoustic events as wakeup candidates for a wakeup phrase for an unsupervised wakeup of a device. It is determined that the first acoustic event is above a second threshold, which is higher than the first threshold, and that the second acoustic event is above a third threshold, which is higher than the first threshold. Occurrence of a wakeup event can be determined based upon acoustic similarity of the events.