JPH0441449Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a magnetic recording and reproducing device having a graphic equalizer, and particularly to a magnetic recording and reproducing device in which the same graphic equalizer can be used in common during recording or reproduction.

BACKGROUND ART Conventionally, a magnetic recording and reproducing apparatus that can use a graphic equalizer when reproducing a recorded magnetic tape has already been proposed. Then, the sound played back from the recorded magnetic tape is corrected according to the acoustic characteristics of the sound field in which the sound is listened to. It will be played back with the values adjusted. However, there are cases where it is desired to make a predetermined correction to the frequency characteristics of the recording audio signal using a graphic equalizer during recording. To achieve this, it was necessary to prepare a separate graphic equalizer and connect it between a recording audio signal generator such as a microphone or record player and a magnetic recording/playback device. In this case, two graphic equalizers are required,
This had the disadvantage of increasing the amount of equipment used. Furthermore, when a single graphic equalizer is used for both recording and playback, the connection has to be changed each time, which is complicated.

DISCLOSURE OF THE INVENTION In view of the above points, the present invention was devised to eliminate the above drawbacks, and it adjusts the same graphic equalizer by switching a switch during recording or when playing back a recorded magnetic tape. The present invention constitutes a magnetic recording/playback device that can be used as a magnetic recording/playback device, and can also stop the operation of a graphic equalizer when it is not needed during recording or playback.

With the above configuration, the present invention enables or disables the graphic equalizer of the magnetic recording/playback device when performing magnetic recording and playback, so that in the same sound field, the graphic equalizer is operated during recording. Since a signal matching the acoustic characteristics of the sound field is recorded on the magnetic tape, it is possible to listen to reproduced sound with corrected acoustic characteristics with good reproducibility. Moreover, since the graphic equalizer is not used during playback in this case, the trouble of adjusting the graphic equalizer is saved.Furthermore, when this magnetic tape is played back and listened to in a different sound field, a graphic equalizer is incorporated into the playback circuit. As a result, it is possible to listen to reproduced sound whose acoustic characteristics have been corrected using a graphic equalizer. By operating or not operating the graphic equalizer in this way, you can select recording and playback modes with a large number of frequency characteristics, and the acoustic characteristics can be corrected even with magnetic tape in various recording conditions. It has the effect of being able to be reproduced, and also to be able to record on a magnetic tape with or without correcting the acoustic characteristics depending on these modes.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a magnetic recording and reproducing apparatus according to the present invention. 1 is a 5-channel graphic equalizer, which has variable resistors for level adjustment of recording audio signals (hereinafter referred to as recording signals) or reproduction audio signals (hereinafter referred to as reproduction signals) in each audio frequency band. filters 2 to 6 and first to fifth bandpass filters 7 to 11 connected to these, respectively.
It is composed of. Here, the audio signal frequency band (f ₀ - _{f 5} ) is the frequency f ₀ - _{f 1} , f ₁ - f ₂ , f ₂ - f ₃ , f ₃
The frequency band is divided into five bands such as ~ _f4 and _f4 ~ _f5 , and the first to fifth bandpass filters respectively pass the recording or reproduction signal of only these divided frequency bands. 12 and 13 are interlocking switches, and when one of them is opened, the other is closed. The interlock switch 12 is used to short-circuit the input and output of the graphic equalizer 1 via the interlock switch 13, and the interlock switch 13 is used to incorporate the graphic equalizer 1 into a recording or playback circuit. belongs to. 14 is a line input terminal from a record player or the like, 15 is a microphone input terminal from a microphone, 16 is a variable resistor for adjusting the recording level or monitor level, and 17 is for amplifying the recording signal from this variable resistor 16. This is an amplifier for 18 is a reproducing magnetic head for reproducing, 19 is an amplifier for amplifying the reproduced signal, and 20 is a variable resistor for adjusting the monitor level of the reproduced signal. 1' is a known noise reduction system, which includes a recording input terminal 1'a, a playback input terminal 1'b, and a monitor output terminal 1'c.
and a recording output terminal 1'd, and when a recording or playback signal is input to the recording input terminal 1'a or the playback input terminal 1'b, the recording or playback signal after noise reduction is used for monitoring. It is output from the output terminal 1'c and the recording output terminal 1'd. A known circuit of a Dolby C type noise reduction system in which integrated circuits of types NE652 and NE654, which are generally sold by Nippon Signetakes, are combined with this noise reduction system 1' is schematically shown. Here, 21,
23 is an analog switch that becomes conductive when playing back a recorded magnetic tape; 28 and 29 are analog switches that become conductive when recording;
24 is an amplifier for amplifying the recording or reproduction signal. 25 is an analog switch connected between the amplifier 17 and the interlocking switch 12;
is the recording input terminal 1'a and the interlocking switch 12,1
analog switch connected between 3 and 30
is an analog switch connected between the monitor connection terminal 33 and the monitor output terminal 1'c,
These analog switches 25, 27, and 30 are closed and conductive during recording. A speaker (not shown) is connected to the monitor connection terminal 33. 36 is an analog switch connected between the monoter output terminal 1'c and the interlocking switch 12, and 26 is an analog switch connected between the interlocking switches 12, 13 and the monitor connection terminal 33. 26 and 36 are closed and conductive when a recorded magnetic tape is reproduced. 31 is a recording amplifier connected to the recording output terminal 1'd of the noise reduction system 1', and 32 is a recording device for inputting the amplified recording signal from the recording amplifier 31 and recording it on a magnetic tape (not shown). It is a magnetic head. Also, by means not shown, the recording analog switch groups 25, 27,
28, 29, 30 or the reproduction analog switch groups 21, 23, 36, 26 are closed simultaneously.

Next, the operation of the magnetic recording and reproducing device according to the present invention will be explained. First, a case will be described in which recording is performed using a microphone (not shown) in sound field A, and the transmission frequency characteristics of sound field A are corrected by a predetermined amount. In this case, close the interlock switch 13,
Recording analog switch group 25, 27, 28, 2
9 and 30 are closed by means not shown. Then, each variable resistor 2 of the graphic equalizer 1
-6 to match the level of each frequency band to the acoustic characteristics suitable for sound field A. The output terminal of a microphone (not shown) is connected to the line input terminal 15, a recording magnetic tape (not shown) is set, and the magnetic tape is run to enter a recording state. Of course, at this time, analog recording switches 25, 27, 28,
It goes without saying that 29 and 30 are closed and conductive. A recording signal from a microphone (not shown) is transmitted to a microphone input terminal 15, a variable resistor 16, an amplifier 17, an analog switch 25, variable resistors 2 to 6 of the graphic equalizer 1, and the first to fifth band pass filters of the graphic equalizer 1. 7～
11, interlocking switch 13, analog switch 27
In this order, noise reduction system 1'
input to the recording input terminal 1'a. The recording signal input to the recording input terminal 1'a is outputted to the monitor output terminal 1'c via the analog switch 28 and amplifier 24, and this signal further passes through the analog switch 29 and amplifier 22 to the recording output terminal. 1'd. The relationship between the output level and the frequency of the recording signal output to the recording output terminal 1'd and the monitoring output terminal 1'c is as shown by curve E in Figure 2 due to the encoding effect of the noise reduction system 1'. Become. This recording signal is inputted to the recording magnetic head 32 via the recording output terminal 1'd and the amplifier 31, whereby the recording signal is recorded on a magnetic tape (not shown). On the other hand, the recording signal output from the monitor output terminal 1'c is output as audio to a speaker (not shown) via the analog switch 30 and the monitor connection terminal 33. Next, a case will be described in which the recorded magnetic tape is reproduced in a sound field B other than the sound field A, and the reproduced signal does not need to be corrected by the graphic equalizer 1. In this case, first, the interlocking switch 12 is closed, and then the interlocking switch 13 on the output side of the graphic equalizer 1 is opened, thereby removing the operation of the graphic equalizer 1 from the reproduction circuit. Next, in response to a reproduction command from an operator (not shown), the recording magnetic head 32 moves away from the recorded and set magnetic tape (not shown), and the reproduction magnetic head 18 comes into contact with this magnetic tape. Of course, at this time, playback analog switch group 2
1, 23, 26, and 36 are closed so as to be in a conductive state, so that when the magnetic tape runs, the magnetic recording and reproducing device is in a reproducing state. A reproduction signal reproduced from a magnetic tape (not shown) by the reproduction magnetic head 18 passes through an amplifier 19 and a variable resistor 20, and then is sent to the reproduction input terminal 1'b of the noise reduction system 1', the analog switch 21, and the amplifier. 2
2. The signal is outputted through the analog switch 23, amplifier 24, and monitor output terminal 1'c in this order.
The characteristics of the output level with respect to the frequency of the playback signal output from the monitor output terminal 1'c of this noise reduction system 1' are the encoding of noise reduction 1' during recording as shown in curve E in Figure 2. The characteristics are flattened by phase correction during recording and playback between the noise reduction 1' decoding characteristics during playback shown by curve D in FIG.
Therefore, the sound output from the speaker is close to the sound signal obtained by correcting the microphone output signal by the graphic equalizer 1.

Next, a case where it is desired to listen to the above-mentioned recorded magnetic tape in the sound field C and where it is necessary to perform correction by the graphic equalizer 1 on the reproduced signal will be explained. First, the interlocking switch 13 is closed and the interlocking switch 12 is opened to incorporate the graphic equalizer 1 into the reproduction circuit. The magnetic recording and reproducing device is put into the reproducing state in the same manner as described above. A reproduction magnetic head 18 outputs a reproduction signal from the recorded magnetic tape. This playback signal passes through an amplifier 19 and a variable resistor 20, then goes through the playback input terminal 1'b of the noise reduction system 1', the analog switch 21, the amplifier 22, the analog switch 23, and the amplifier 24 in this order, and is output for monitoring. Terminal 1'
Output from c. And this signal is further
Analog switch 36, graphic equalizer 1, interlocking switch 13, analog switch 26,
The sound is output as audio to a speaker (not shown) through the monitor connection terminal 33 in this order. Here, since the variable resistors 2 to 6 of the graphic equalizer 1 are adjusted by a predetermined amount according to the acoustic characteristics of the sound field C, the sound output from a speaker (not shown) matches the acoustic characteristics of the sound field C. ing. In addition, if you want to play back a magnetic tape recorded without using a graphic equalizer with this magnetic recording and playback device and listen to the reproduced audio in accordance with the acoustic characteristics of the sound field, use the same playback method as above. You can listen to it. In addition, before taking the reproduction signal from the magnetic tape, the reproduction analog switch groups 21, 23, 26, and 36 are closed to make them conductive, and the graphic equalizer 1 is adjusted in accordance with the sound field in the same way as in the above case. There is a need to. Although the noise reduction system is a Dolby C type system as an example, it is not limited to this, and any known noise reduction system may be used.

By constructing and operating the present invention as described above, the graphic equalizer of the magnetic recording and reproducing device can be operated or not operated during magnetic recording and reproduction. Therefore, it has the effect that recording and reproducing operations in various states can be performed with less complexity. By activating or not activating the graphic equalizer, you can select a large number of modes, and any magnetic tape can be played back with its acoustic characteristics corrected. This has the effect of making it possible to record onto a magnetic tape with or without correcting the acoustic characteristics.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a magnetic recording and reproducing device according to an embodiment of the present invention, and Fig. 2 is an explanatory diagram showing the relationship between output level and frequency output from a Dolby C type noise reduction system. be. 1... Graphic equalizer, 1'... Noise reduction system, 2 to 6... Variable resistor, 7 to 11... First to fifth band pass filters, 12, 13... Interlocking switch, 14... Line input terminal, 15...Microphone input terminal, 18...
Reproducing magnetic head, 21, 23, 26, 36...Analog switch, 25, 27, 28, 29, 30
...Analog switch, 21, 23, 26, 36
...Recording analog switch group, 25, 27, 2
8, 29, 30... Analog switch group for playback,
32... Recording magnetic head.

Claims (1)

[Scope of utility model registration request] In a magnetic recording and reproducing device equipped with a graphic equalizer and a noise reduction system, when recording a recording signal on a magnetic tape, the graphic equalizer is placed before the noise reduction system when recording using the graphic equalizer. a group of recording analog switches for switching wiring connections according to the arrangement; and a group of recording analog switches for switching the wiring according to the arrangement, and a noise reduction system that uses the same graphic equalizer when reproducing audio from a recorded magnetic tape. A group of playback analog switches for switching the wiring so as to be placed in the latter stage, and an interlocking switch for short-circuiting the input and output terminals of the graphic equalizer when the graphic equalizer is not used during recording or playback. A magnetic recording/playback device characterized by: