AN INDICATION DEVICE FOR SOUND PRODUCING EQUIPMENT IN WHICH A MEMBER HAVING A CUTOUT IS SECURED TO A STATIONARY PART OF A VARIABLE RESISTOR AND A FORWARD END OF A PLATE SECURED TO A MOVABLE PART OF THE VARIABLE RESISTOR IS INSERTED IN THE CUTOUT OF THE MEMBER SO THAT THE PORTION OF THE PLATE LIES ON THE MEMBER IN SUPERPOSED RELATIONSHIP. BY MOVING THE ROTARY PART, THE AMOUNT OF THE EXPOSED PORTION OF THE PLATE SECURED TO THE MOVABLE PART IS INCREASED OR REDUCED, SO THAT VARIATIONS IN THE VALUE OF RESISTANCE IS INDICATED BY THE AMOUNT OF THE EXPOSED PORTION OF THE PLATE.