Sony Corporation

Kazuo Murayama

Kazuyuki Suda

Toshiya Murakami

A speaker apparatus has a frame to which a convex paper is attached. A bobbin with a voice coil is attached to the paper cone. A magnetic circuit is formed inside the frame. A damper suspending the bobbin is composed of a corrugation portion, which is positioned orthogonal to the bobbin in an inactivity of the speaker apparatus. The damper also includes a first leg portion extending forward along a vibration direction of the bobbin from an inner periphery end of the corrugation portion, and a second leg portion extending backward along the vibration direction of the bobbin from an outer periphery end of the corrugation portion. The first and second leg portions have substantially the same length.

Speaker apparatus

A changeover circuit in a tape recorder includes a recording and reproducing integrated circuit (IC) having a signal terminal and a bias terminal and arranged such that a DC potential at the signal terminal is set equal to that at the bias terminal, a changeover transistor whose collector and emitter are connected between a signal line connected to the signal terminal and the bias terminal, a controller for controlling the changeover transistor by supplying an output therefrom through a resistor to a base of the changeover transistor, and a bypass circuit connected between the bias terminal and a ground. The bypass state of the bypass circuit is controlled based on a control voltage from the controller.

Changeover circuit in tape recorder

A sound quality adjustment circuit including a status variable type active band-pass filter having an amplification circuit fed with an input signal and an integration circuit, and a controller for controlling the conversion conductance of the amplification circuit. The center frequency of the status variable type active band-pass filter is continuously varied by controlling the conversion conductance of the amplification circuit by the controller.

Sound quality adjustment circuit

An automatic fast action automatic reversing tape recording system comprising a first detecting circuit for generating a first output signal which changes from one state to another state only when the end of the record coated portion of the tape is detected by the sensor in the forward mode of the apparatus, a second detecting circuit for generating a second output signal which changes from one state to another state only when a non-recorded area of the tape is detected in the fast-forward or fast-rewind mode of the apparatus, a third detecting circuit to which both of said first and second output signals are supplied for generating a switching signal to change the mode of the apparatus when either of said output signals is maintained in said another state for predetermined times measured by the same time constant circuit. The third detecting circuit may include an integration circuit which is charged to different DC voltages by said first or second output signals which are in their one state in response to the mode of the apparatus and are then discharged along a time constant from a time when each of said first or second output signals changes to its said other state.

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Kanagawa, Japan

Kazuo Murayama