ELECTRICAL DEVICES AND APPARATUS-NAMELY, MICROPHONES, MICROPHONE ENCLOSURES, [ MICROPHONE SWITCHES, ] MICROPHONE AMPLIFIERS AND POWER SUPPLY UNITS THEREFOR; PROTECTIVE CAPS FOR MICROPHONES FOR ELIMINATING WIND AND OTHER NOISES; MICROPHONE TRIPODS AND STANDS FOR HOLDING, SUSPENDING AND ATTACHING MICROPHONES; FITTINGS FOR INSTALLING MICROPHONES ON TRIPODS, STANDS, GANTRIES AND SOLID SUPPORTS; MICROPHONE CABLES; EARPHONES [, AND LOUDSPEAKERS ]