Length-Adjustable Collapsing Headband

A length-adjustable collapsible headphone comprising:

• a) a headband comprising an upper section, a right lower section, and a left lower section, the upper section comprising an inner headband arm and an outer headband arm, the right lower section and the left lower section each comprising a scissor arm assembly having an inner scissor arm and an outer scissor arm, each of the inner scissor arms and the outer scissor arms comprising slide adjustment sub-assemblies;
• b) a pivot joint that connects the outer headband arm to the inner headband arm so that the outer headband arm and the inner headband arm can rotate freely around an axis of the pivot joint;
• c) a left keyhole pivot assembly that connects the inner scissor arm to the outer scissor arm in the left lower section and a right keyhole pivot assembly that connects the inner scissor arm to the outer scissor arm in the right lower section, wherein an axis of the left keyhole pivot assembly and an axis of the right keyhole pivot assembly are each aligned with the axis of the pivot joint so as to maintain a common centerpoint of each of the left keyhole pivot assembly axis, the right keyhole pivot assembly axis, and the axis of the pivot joint, thereby allowing the headphone to collapse in spherical motion to a space efficient closed state;
• and
• d) at least one earcup assembly connected to at least one of the right and left keyhole pivot assemblies with a yoke using a swivel joint that allows the at least one earcup assembly to yaw around the axis of the swivel joint, the earcup assembly being configured to fit over a user's ear.