Abstract: An audible tone identifier comprises a transducer and amplifier for responding to audible tones, such as generated by a human voice speaking or singing, or a musical instrument, and a plurality of filters sharply tuned to the notes of one or more octaves or fractions thereof of the equal tempered chromatic musical scale or to other patterns of sounds that are to be individually identified. The outputs of the filters are connected to lamp driver circuits which in turn are connected through transposing plug-and-jack connectors and sharp-and-flat insertion switches to lamps on a display board, whereby any musical tone within the range of the device, received by the transducer, will be identified visually on the display board by the lighting of a lamp.