Abstract: A dummy listener and right and left speakers 13 and 14 are disposed in an anechoic room as a model of the layout of those a car cabin 15 or the like. Transfer functions ALL, ALR, ARL and ARR in a space ranging from the speakers 13 and 14 to the right and left ears of a listener 16 in a car cabin 15 or the like are calculated from impulse response series aLL(t) to aRR(t) obtained when pulse sounds are respectively emitted from the speakers 13 and 14. A correction circuit 10b contains correction transfer functions H11, H12, H21 and H22, which are obtained by an inverse matrix of a 2-row and 2-column regular matrix of which the elements are the transfer functions ALL, ALR, ARL and ARR. Audio signals SL and SR on which head related transfer functions are superimposed are applied to the correction circuit 10b, and the output signals of the correction circuit 10b are supplied to the speakers 13 and 14.

Abstract: A lower side of a rotatable grindstone spindle is connected directly to a PZT (Piezoelectric element). By changing electric drive supplied to the PZT, reciprocating movement can be applied to the grindstone through the grindstone spindle in addition to rotational movement. As a result, the grinding locus of an abrasive grain of the grindstone on a taper surface of a workpiece becomes a sine wave, and therefore, the grinding locus can be shifted in a direction other than in a peripheral direction. In this way, the removed amount of the taper surface increases, and circularity of the taper surface can be made to equal to 0.3 .mu.m or less.

Abstract: A digital graphic equalizer for obtaining a boost characteristic and an attenuation characteristic using band pass filters, each constituted by a digital filter, and an adder. For a boost characteristic, an input signal is supplied to first band pass filters and resultant filtered signals and the input signal are added by a first adder. For an attenuation characteristic, the output signal of a second adder is fed back to second band pass filters and resultant filtered signals and the input signal are added by a second adder.

Abstract: A stator of a steering angle sensor is fixed to a steering column through a combination switch case and a stationary bracket, and a rotor of the sensor is rotatably fitted over a steering shaft. A locking collar is slidably but nonrotatably connected to the rotor. The locking collar and the stator are respectively provided with a locking groove and a locking tooth which engage each other to lock the rotor in a predetermined rotational alignment. When the steering angle sensor is not mounted to a vehicle, the locking groove and the locking tooth are brought into engagement with each other by a locking spring to lock the rotor. When a steering wheel is mounted to the steering shaft in a predetermined rotational neutral position of the steering shaft, a clamping pressure caused by the mounting causes the locking collar to be moved to a lockreleasing position or disengage position and the rotor is connected to the steering shaft.

Abstract: A method of preparing an inorganic porous member causes a layered inorganic compound in swelled state with a solvent contained therein to be dried in a super critical state, so as to have holes held between respective layers of the inorganic compound, whereby the layered compound can be excellently maintained with less agglomeration caused upon removal of the solvent and the hole volume in the entire inorganic porous member can be remarkably increased.