JPS5819693Y2 - hiss noise - Google Patents

Description

[Detailed description of the invention] This invention records the playback signal of a record player on the magnetic tape of the Q7 recorder, and effectively eliminates the hiss noise generated when the signal recorded on the magnetic tape is played back with the magnetic head. The present invention relates to a hiss noise reduction device that eliminates hiss noise.

Generally, music signals are recorded on records according to a frequency characteristic called RIAA%, which emphasizes high-frequency components compared to low-frequency components.

Therefore, if a signal reproduced from a record is recorded as is on a magnetic tape, and then this signal is reproduced as is with a magnetic head, an unnatural sound will be heard.

For this reason, in conventional audio equipment, the RIAAW characteristics are corrected as shown in FIG.

In Figure 1, 1 is a record player, 2 is a preamplifier (hereinafter referred to as preamplifier), 3 is a tape recorder,
4 is a selector switch, 5 is a volume for adjusting sound quality and volume, 6 is a power amplifier (hereinafter referred to as main amplifier), 7
is a reproduction signal output terminal, and this output terminal 7 is connected to a speaker (not shown).

Note that the preamplifier 2 and main amplifier 6 are each equipped with a feedback circuit consisting of resistors R1 and R2, capacitors CI and Cz, and resistor R3.

Note that a indicates the playback output end of the record player 1, b indicates the recording input end of the tape recorder 3, and C indicates the playback output end of the tape recorder 3.

In the above configuration, the frequency characteristic of the signal reproduced by the record player 1 has an RIAA% characteristic in which the high frequency range is emphasized compared to the low frequency range, as shown in FIG. 3(d).

And preamplifier 2 consists of resistors R1, R2, and capacitor CI.
, C2 is added, so its frequency characteristics (as shown in Figure 3a) attenuate the high frequency range.

Therefore, the output characteristic of the preamplifier 2 becomes a flat characteristic over the entire region as shown in FIG. 3a, and a signal having such a characteristic is recorded on the magnetic tape.

As a result, the signal reproduced from the magnetic tape by the magnetic head also has a flat characteristic as shown in Figure 3a, but at this time, due to the contact between the magnetic tape and the magnetic head, the wavy line in Figure 3a A jade noise as shown is generated.

The reproduced signal and jade noise are then supplied to the main amplifier 6 via the selector switch 4 and volume 5.

Here, since the main amplifier 6 has a flat frequency characteristic as shown in FIG. Become something.

For this reason, the unnatural feeling of emphasized high frequencies is removed, allowing the user to listen with a natural feeling.

However, in this case, as is clear from FIG. 3a, the hiss noise is also reproduced as is, and there is a problem if this hiss noise becomes a harsh sound.

The present invention provides a hiss noise reduction device that can easily solve these problems.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

In FIG. 2, parts having the same functions as those in FIG. 1 are denoted by the same reference numerals, and explanations thereof will be omitted.

And for Noriamp 2, resistor R1, R2 capacitor CI
.

In addition to C2, there are also capacitors CI and a switch S1 for connecting and disconnecting C2. A feedback circuit with S2 is provided, and the main amplifier is also provided with a feedback circuit with resistors R4) R5, capacitors C3, C4, and switches S3, S4.

First, a case in which RIAA recording is performed using the above configuration will be described.

At this time, switch SL. S2 is turned off to make the frequency characteristics of the preamplifier 20 flat over the entire range as shown in FIG.

In this way, the output characteristics of the preamplifier 2 will have RIAA characteristics with emphasized high frequencies, as shown in FIG. 3, and a signal having such characteristics will be recorded on a magnetic tape.

Therefore, the signal reproduced from the magnetic tape by the magnetic head also has RIAA characteristics.

At this time, as in the conventional case, hiss noise as shown by the dotted line in FIG. 3 is generated, and these signals and hiss noise are supplied to the main annolo.

Here switch S3. Turn on S4 and turn on main amplifier 6
If the frequency characteristics of the speaker are made to attenuate the high frequencies as shown in Figure 3, the output characteristics will be flat, and as a result, the frequency characteristics of the sound reproduced from the speaker will also be flat. This can eliminate unnatural sensations.

Furthermore, when the main amplifier 6 corrects the RIAA% characteristic, the high frequency range of the hiss noise is attenuated, so that the harsh hiss noise can be effectively removed.

Next, when performing 1/2 RIAA recording, turn on switch S1 and turn off switch S2, correct only the low range with preamplifier 2 as shown in Figure 3C, turn off switch S3, and turn off switch S4. All you have to do is turn it on and correct the high frequency range using the main amplifier 6 when playing back the tape.

Even in this manner, as in the case of RIAA recording, unnaturalness of the reproduced signal can be removed and hiss noise can be reduced.

As described above, according to the present invention, the hiss noise generated during tape playback can be removed very easily and effectively, and excellent effects can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional audio device, FIG. 2 is a block diagram showing an audio device using a hiss noise reduction device according to an embodiment of the present invention, and FIG. 3 is an explanatory diagram of the operation of the above embodiment. . 1... Record player, 2... First amplifier (preamplifier), 3... Tape recorder, 4... Selector switch, 5... -Volume, 6...Second amplifier (main amplifier), 1...Output terminal.

Claims (1)

[Scope of utility model registration request] The playback signal of the record player is connected to the RIA between the playback output end of the record player and the recording input end of the tape recorder.
A or 1/2 RIAA A first amplifier having a frequency characteristic that amplifies the signal with the same characteristic is inserted, and the RIAA or 1/2 RIAA signal of the playback signal of the tape recorder is inserted between the playback output terminal of the tape recorder and the speaker. 2RIAA
This is a hiss noise reduction device that includes a second amplifier having frequency characteristics that corrects for % noise.