Abstract: A cleaning device for cleaning phonograph records comprises a grip member th at least one cleaning insert engaged with the grip member and having a record engaging cleaning surface which projects outwardly therefrom which is adapted to rest upon a record to be cleaned. The surface may advantageously be covered by a ribbon or other cleaning cloth which may be wetted with a cleaning liquid. The grip member is provided with a bearing pressure weight member which acts through the grip member on the insert to apply a predetermined cleaning pressure to the record. The grip member advantageously comprises a member having a trough facing outwardly from each side into which an insert is positioned and a weight member is disposed therebetween the trough members. One of the inserts is adapted to rest in a cleaning housing or case so that it contacts a wick which is wetted with cleaning liquid so that its surface or the surface of a cleaning cloth wrapped therearound is wetted at all times.

Abstract: An arrangement for headphones for converting frequency modulated audio oscillations into amplitude modulated oscillations, and particularly for rendering audible the vibrato of electronic musical instruments, such as electronic organs, includes a housing having an electroacoustic transducer therein with a diaphragm having a smooth frequency response zone which is connected to at least one mechanical transit-time member having a transit time from one end to the other not greater than 20 ms. The transit-time member is advantageously a helical spring which extends axially through the electroacoustic transducer or through a central ferromagnetic core thereof. The portion of the spring within the core is advantageously made of a thicker wire and of a smaller diameter than the remaining core so that it does not contact the walls thereof.