FIELD: physics.
SUBSTANCE: plaque has a frame with apertures in which reeds with rivets are placed. The frame has a profile in the cross-section which narrows towards its base. Each aperture of the frame has a cross profile in form of a trapezium with narrowing towards the reed. Rivets are placed on the surface of the frame along a line which passes at an acute angle to the nearest lateral edge of the frame. Said line approaches said edge in the direction towards the region of high tones of the plaque. At least two last pairs of reeds in the region of high notes of the plaque are directed opposite the remaining pairs of reeds.
EFFECT: improved plaque.
2 cl, 2 tbl, 3 dwg
