Abstract: This invention relates to a magnetic recording and reproducing device in which automatic settings of optimum recording bias current, optimum recording level and optimum recording equalization characteristic are successively accomplished in this order. The settings of the optimum recording conditions are achieved with high accuracy within short period of time by a computer control using a microprocessor.

Abstract: A magnetic-tape sound recorder which features a computer-controlled adjusting device capable of automatically adjusting the recording signal level and the recording bias current depending upon the magnetic tape to be put to use on the sound recorder.

Abstract: A method and an apparatus for detecting and automatically setting optimum recording bias in a tape recorder in which first and second test signals of low and high audio frequencies, respectively, are alternately recorded on a recording medium. While these are being recorded, the recording bias applied to the recording medium is varied in a plurality of steps between upper and lower limits. The tape is then rewound and the reproduced first and second signals are compared to determine at which recording bias step the reproduced levels of the first and second signals are equal to one another. The recording bias for normal recording is then set in accordance with the bias level present at the selected step.

Abstract: This invention relates to a magnetic recording and reproducing device in which automatic settings of optimum recording bias current, optimum recording level and optimum recording equalization characteristic are successively accomplished in this order. The settings of the optimum recording conditions are achieved with high accuracy within short period of time by a computer control using a microprocessor.