Abstract: Provided concerns a device for treating water of the kind intended for treating running water from a domestic water supply system or other sources of pressurized water, to obtain filtered or treated water, for example, of drinking water quality.

Abstract: This invention relates to electro-acoustic transducers such as is generally indicated at 10 and which comprise a body 11 defining a chamber 12, a plate 13 bearing a micro-phone or speaker 14 to which is attached a stalk 15, a diaphragm 16, connectable to the stalk 15, which extends substantially across the chamber 12, an end piece 17 and an end cap 18. The end piece 17 has a kidney-shaped recess 21 which provides the main communication path between subsidiary inlets/outlets 19 and a main inlet/outlet 20. When the channel 22 is closed off by the end cap 18 it is effectively in the form of a tube and constitutes a Thuras tube. The length of this path effectively creates a long discharge path between the wearers' ear and any grounded metal part within the transducer and hence protects against electric shock.

Abstract: A toy megaphone including a housing having a number of openings formed in the upper end, a member fixed in an upper portion of the housing, and a spring biased between the member and a lower end of the housing, and the member and the spring being caused to vibrate when a sound wave is propagated into the housing via the openings.

Abstract: A device for communicating in which a hollow frustum extending outwardly from a flat base has tabs at the ends thereof for holding a relatively rigid diaphragm having spaced apart apertures therein. A pair of these devices are interconnected by a cord or string, whereby conversation or sound projected into one of the devices is reproduced at the other device. Two devices are molded as a single integral unit and merchandised as an in-pack item with children's breakfast cereals.

Abstract: An apparatus and method for producing sound, particularly unusual sound effects, wherein the apparatus comprises at least one diaphragm and a spring attached to the diaphragm, having a lowest resonance frequency less than 18 hertz. The apparatus includes a resonator affixed to the diaphragm.According to the method of the invention, sounds are produced on an instrument having a spring and a diaphragm connected to the spring by exciting an echophone frequency of the spring by either activating longitudinal motion of the spring, jerking at least one end of the spring in a longitudinal direction, longitudinally displacing and releasing a section of the spring, and moving at least one end of the spring longitudinally in a rhythmic motion to excite an echophone frequency.

Abstract: An opto-acoustic telephone receiver, for converting optical signals propagating in an optical fiber waveguide into audible acoustic signals, includes an optical absorption cell having a volume of the order of 10.sup.-.sup.3 cm.sup.3, acoustically coupled to the narrow end of a tapered acoustic tube whose wide end can be acoustically coupled to a human ear.