A musical sound signal generation device comprising: a delay line provided with a plurality of delay units which are connected in a cascade manner and respectively delay input signals (x(n)) by a first delay length; at least three fractional delay blocks each of which is connected to correspond to any delay unit among the plurality of delay units and delays an input signal (x(n)) by a second delay length equal to or less than the first delay length; and at least one processor that sets any one of the plurality of delay units as a first delay unit which generates a delay corresponding to a designated tone pitch, sets a delay unit in a preceding stage of the first delay unit among the plurality of delay units as a zeroth delay unit, and sets a delay unit in a subsequent stage of the first delay unit among the plurality of delay units as a second delay unit, wherein the at least one processor connects the at least three fractional delay blocks to the first delay unit, the zeroth delay unit, and the second delay unit, respectively, and continuously connects any one of the connected zeroth delay unit and the connected second delay unit to the fractional delay block and connects at least any one of a new zeroth delay unit and a new second delay unit to at least any one of the fractional delay blocks other than the fractional delay block connected to a new first delay unit in response to setting any one of the connected zeroth delay unit and the connected second delay unit as the new first delay unit, setting a delay unit in a preceding stage of the new first delay unit as the new zeroth delay unit, and setting a delay unit in a subsequent stage of the new first delay unit as the new second delay unit in accordance with a change in the designated tone pitch. a delay line provided with a plurality of delay units which are connected in a cascade manner and respectively delay input signals (x(n)) by a first delay length; at least three fractional delay blocks each of which is connected to correspond to any delay unit among the plurality of delay units and delays an input signal (x(n)) by a second delay length equal to or less than the first delay length; and at least one processor that sets any one of the plurality of delay units as a first delay unit which generates a delay corresponding to a designated tone pitch, sets a delay unit in a preceding stage of the first delay unit among the plurality of delay units as a zeroth delay unit, and sets a delay unit in a subsequent stage of the first delay unit among the plurality of delay units as a second delay unit, wherein the at least one processor connects the at least three fractional delay blocks to the first delay unit, the zeroth delay unit, and the second delay unit, respectively, and continuously connects any one of the connected zeroth delay unit and the connected second delay unit to the fractional delay block and connects at least any one of a new zeroth delay unit and a new second delay unit to at least any one of the fractional delay blocks other than the fractional delay block connected to a new first delay unit in response to setting any one of the connected zeroth delay unit and the connected second delay unit as the new first delay unit, setting a delay unit in a preceding stage of the new first delay unit as the new zeroth delay unit, and setting a delay unit in a subsequent stage of the new first delay unit as the new second delay unit in accordance with a change in the designated tone pitch.