Wondrous item, uncommon
The bird has 7 charges and regains all of them at dawn. As an action you set the key to a notch and expend 1 charge; the bird sings that air for 1 minute, or for an hour in the case of the third. The effect of each of the first six airs is as entered in the maker's list above. The airs cannot be muffled, hurried, or played over one another, and the bird will not sing with the cage door open.
The seventh notch is the reason for the price. While the seventh runs — 1 minute — no sound made within 20 feet of the cage can be heard by anything outside that space, and no sound from outside is heard within it. Speech, bells, gunfire and screaming all stop at the edge of it. Inside, everything is heard as usual, including the bellows, which are the only thing in the cage that makes a noise.
The bird does not sing the seventh air. It opens its beak for the length of the minute and turns upon the perch at the end, as it does for the other six.
Source: Provenance — The Quist Sale