JPS607300A - Audio signal processing system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION In particular, the "KJIKAI 1. Regarding the audio playback system
+J Ll Low frequency skin of stereo audio signal/z.
l4 :j′Y. Is 臥min, e.g. about 100Hz J
'': Some boosting of the frequency below
(U.S. 11 Patent No. 4,18
2,930.

Frequencies in the bass scale range, e.g. approximately 2 4] lh and 5
A significant amount of the signal energy in the 0 Hz range is lost when the audio signal or recording is played back after transmission.

Therefore, for high-quality and more realistic reproduction, it is desirable to combine the above-mentioned signal energy and the original recording magic when the expulsion characteristics of audio Kagawa allow. The system described in U.S. Pat. No. 4,182,930 is
The signal energy of the audio signal in a predetermined frequency range of the audio signal, for example, between 40 Hz and 00 Hz, is sensed by primarily existing in the frequency range where the signals are synthesized.

The sensed signal energy is then divided into a number of discrete, very narrow frequency band components, and each component present in the signal can be used to generate a subharmonic signal of that component. The subharmonic signal is then added to the original audio signal. In a stereo system, the subharmonic signal is extracted and then added to both channels. However, within this low frequency range, such boosting of low frequency components usually results from the vertical movement of the record stylus, e.g. turntable rumble noise, the descent or rise of the record stylus onto the record plate, as well as the sound PI feedback. This results in an increase in undesirable noise associated with out-of-phase components.

It is therefore an object of the present invention to provide a system for amplifying low frequency components in a stereo audio signal sufficiently independently of out-of-phase components associated with, for example, vertical movement of a record stylus.

The above and other objects of the invention provide an improved signal processing system of a type suitable for use within an audio reproduction system, comprising a device comprising at least two input terminals each receiving two stereo information signals; achieved by. The signal processing system includes a pair of 46 paths for respectively applying two audio input signals to the input terminals of the corresponding device, each signal path having an input terminal for receiving one of the input signals. and an output terminal for coupling a signal path to the device. The signal processing system also includes means coupled to the signal path for generating a summation signal representing a sum of the input signals; means for amplifying a low frequency component of the summation signal; and means for amplifying a low frequency component of the summation signal; to each system output terminal of the signal path so that the low frequency components of the audio input signal are amplified independently of the vertical components of the input signal.

Other purposes will be made clear below.

That is, the present invention includes the construction and combination of elements and apparatus for compounding the parts as exemplified in the scope of application indicated in the following detailed description and claims.

Without departing from the scope of the invention contained herein.''
-6 Although it is possible to modify the device 6 as appropriate, all matters shown in the above description and the attached drawings should be interpreted as one example and in a limited sense. Needless to say, it is not.

In the figures, the same parts are referred to with the same numbers.

With particular reference to FIG. 1, the system receives 25 right and left channel signal inputs from the output of a preamplifier such as a tape system, receiver or turntable not shown.
It is now available for OA and 250B. These inputs 250A and 250B are the inputs to the main signal path of the system. Inputs 250A and 250B are connected to an input matrix 262, the latter receiving right and left channel inputs, L+R outputs and L-
It is designed to give R output. As is well known, L+R
The output is a vinyl recording modulation of a stereo signal (Vinyl r
echo modulation), while the L-4 signal contains a vertical component, such as the ambient Te3 signal. The L + R output is a low frequency equalization control circuit.
ion control circuit) 264, while the L-R outputs are connected to an output matrix 268, which receives the L+R outputs from circuit 264 and the L-R outputs of matrix 262, and receives the left and right outputs. Gives channel output.

In accordance with the present invention, low frequency equalization circuit 264 is adapted to increase the low frequency energy delivered at the output of the L 1 R output of input matrix 262. Here the following should be evaluated: That is, since the signal input to the low frequency equalization circuit 264 is the L+R component, it does not contain any out-of-phase vertical components of the audio signal, such as turntable ripple noise. This is because the two signals R and R are matrix 2
This is because the vertical components are canceled when added together by 62. Thus, circuit 264 does not boost the vertical noise component. The output of the control circuit is added to an output matrix 268. .

When the matrix 26 is modulated by the low frequency equalization control circuit 264, it is applied to the left channel signal L output terminal 270A. Similarly,
The matrix 268 outputs the right channel signal R at a frequency of 1
When modulated by the anti-equalization control circuit 264, it is applied to the output terminal 270B.

In operation, the system of FIG. 1 boosts the low frequency portion of the audio signal in the two channels substantially independently of out-of-phase low frequency vertical noise components, such as turntable ripple noise. This is accomplished by utilizing an input matrix 262 that sums the left and right channel signals to provide an L+R summation signal.

Since the L-1-R addition signal does not contain out-of-phase low-frequency vertical noise components, the low-frequency equalization control circuit 264
The low frequency portion of the signal is boosted sufficiently independently from the out-of-phase vertical noise component. Therefore, if the signal is split into left and right channel signals for each channel, the low frequency portion will trough the boosted bass portion of the signal without noise components. On the other hand, it should be noted that the low frequency J21 portion in the output of matrix 268 is mono audio, and most program information includes low frequency mono audio components.

A preferred embodiment of the system shown in FIG. 1 is shown as a block diagram in FIG.

Referring to Figure 2 in detail, since the system is capable of connecting a cheap recorder, turntable, or receiver to receive any power, each power 250A and 250B is It includes an outlet to connect the system to any type of audio program source. The right channel power provided by the audio program source is applied through terminal 250A to resistor 600' and through resistor 600 to connection point 602. The left channel input provided by the audio program source is applied through terminal 250B to resistor 604 and then through resistor 604 to connection point 602.

By having resistors 600 and 604 of the same value, the left and right signals are combined at connection point 602 to represent the L+R signal output of the matrix.

To form the LR signal, the left channel power provided by the audio program source is applied through terminal 250A to resistor 606 and through resistor 606 to the inverting input of amplifier 608. The right channel input provided by the audio program source is at terminal 250B.
JL to the resistor 610 through JL, and then the resistor 610
to the non-inverting input of amplifier 608. The non-inverting input is then connected to system ground via a resistor 612. The output of amplifier 608 is connected to the inverting input via feedback resistor 614. Resistance 60G
and 610 are the same, so that the output of amplifier 608 acts as a subtractor and provides the LR signal.

The L+R signal provided at connection point 602 is provided to a low frequency reduction control circuit 264 shown in FIG. More precisely, node 602 connects to the inverting input of amplifier 616, which is connected to feedback resistor 618 and then to node 60.
2 has an output applied to its inverting input via 2. The non-inverting input of amplifier 616 is connected to system ground through resistor 620.

The output of amplifier 616 is connected through resistor 622 to the inverting input of amplifier 6240.

The non-inverting input of the latter amplifier 624 is connected to system ground, and the output is still connected to amplifier 616 via resistor 626.
connected to the non-inverting input of the The output of amplifier 624 is still coupled to the inverting input of that amplifier via feedback capacitor 628. The output of the Ushita increase 1 quotient 624 is
It is connected through a resistor 630 to the inverting input of an amplifier 632. The latter amplifier 632 has a non-inverting input connected to system ground, and the output is connected to a feedback capacitor 634.
to its own inverting input. amplifier 6
The output of 32 is connected to the inverting input of amplifier 616 via feedback resistor 636.

The output of amplifier 632 is also connected via capacitor 638 to a resistor of potentiometer 640 fl, which is connected to system ground.

Furthermore, the output of the amplifier 632 is connected via a capacitor 642 to a resistor Me of a potentiometer 644, which is connected to system ground. The connection point formed between the capacitor 638 and the one-pot difference meter 640 is connected to the connection point formed by the capacitor 642 and the potentiometer 644, and the two connection points are connected via a resistor 646 to the connection point formed by the capacitor 642 and the potentiometer 644. is connected to the inverting input of amplifier 648 shown in FIG. The inverting input of the amplifier 648 is connected to the resistor 61 via a feedback resistor 650.
8, connected to the junction formed by amplifier l1i16 and resistor 622. The inverting input of the power amplifier 648 is connected to the wiper arm of the 1i differential meter 644 via a resistor 652, and is also connected to the wiper arm of the low lid meter 640 via a resistor 654.

The non-inverting input of amplifier 648 is connected through a resistor 656 to the junction formed by the output of amplifier 624 and resistor 626. Resistance j1. The connection formed between I'L 626 and 656 is connected to system ground through the resistor of potentiometer 660 and
62 to the wiper arm at potential i'gfl 660. The non-inverting input of J1'Q width amplifier 648 is
It is connected to the wiper arm of the one-place difference meter 660 through a resistor 664, and to the system ground through all resistors 666. The wiper arms of potentiometers 644 and 660 are interlocked to allow for a low frequency boost (open side) controlled by control circuit 264. The output of amplifier 648 is the feedback low 1't'lX66
Connected via B, low frequency equalization: l+lI i4
It forms the output of one circuit 264. Therefore, amplifier 6
The output of 48 is connected to the L+R human power of an output matrix 268, which will be described later.

Human power matrix 26 applied to the output of amplifier 608
The L-R outputs of 2 are connected to the output matrix shown in FIG.

Specifically, to form the left channel output signal from matrix 268, the output of amplifier 648 is connected to resistor 7.
50 to a second resistor 752 which is connected to the left channel output of the matrix as indicated by connection point 754. The output of amplifier 720 in FIG.
58 and to the system ground via resistor 762. Amplifier 75
The outputs of 8 are connected to terminal 270A to provide the 17 signal outputs of output matrix 268. Right channel signal I
In order to make an Eke-shaped J, the output of the widening device 648 is lJ (
It is connected through a resistor 764 to an inverting input of an amplifier 766, and the inverting input has an output connected to a terminal 270B which provides the left channel signal output of the matrix 268.

The output of amplifier 166 is connected through a feedback resistor 768 to its inverting input. The output of amplifier 608 of input matrix 262 in FIG. 2 is connected through a resistor 7γ0 to its inverting input. Finally, the non-inverting input of amplifier 766 is connected to system ground through resistor 774.

The reconstructed L and R signals appear at terminals 270A and 27OB, respectively.

In the preferred embodiment of the system shown in FIG. 2, the resistors and capacitors have the values shown in Table B below, where for light B the resistance is designated by the initial letter R and its value is in ohms; Still the condenser is denoted by the initial C and its value is in farads. The letter X\ is for cow Room,\\
M〃 stands for megaohm, X'″uf〃 stands for microfarad, \\nf stands for nanofarad, and 11 pf II stands for picofarad.

Table B Input matrix 2G2 Element Value R6007,5K R604,7,5K R60610K R6], 0 10K R612]0K R614j OK Low frequency equalization control circuit 264 Element Value R6187,5K Ft 620 75 (I R62239' K R6261 0K C6280 , ]Iu f630 39 K C6340, Iuf Table B (continued) R636], OK CG3 8 0.1 u f R64020K C6424,7uf R6/W 10 K R6'16 47K R65033K R6523K R6544,7M R6561 50K R66010K R6623K R66lI l0K R66( i 4.3 K II G 6 8 3 Table B (Continued) which provides a boosting of the low frequency portion of the audio signal in the two channels sufficiently independent of the outlying low frequency vertical noise components. This is accomplished by using the input matrix 262 shown in FIG. In this case, the matrix is such that the left and right channel signals are summed at connection point 602 to obtain L-1-R+3').

Since the smart L/R addition signal does not carry out-of-phase low-frequency vertical noise components, the amplifiers 616, 624 and 632 of the low-frequency equalization control circuit 264 separate the low-frequency portion of the signal from out-of-phase vertical noise components. Can be boosted independently.

Accordingly, the present invention provides an improved audio reproduction system that boosts the low frequency components of the audio signal in two channels sufficiently independently to reduce the out-of-phase low frequency vertical 4nL:if acid components, such as turntable ripple noise. be.

All matter contained in the foregoing description and accompanying drawings is to be construed as illustrative, as suitable modifications may be made to the above apparatus without departing from the scope of the invention contained herein; Limiting the invention. There's no need to say that you shouldn't taste the bamboo shoots.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a preferred embodiment of an audio system constructed according to the present invention, and FIG. 2 is a block diagram of a preferred embodiment of the system shown in FIG. [Explanation of symbols of main parts] 250A...Right channel input 250B'
-°゛°・Left channel input 262...Input matrix 264...Low frequency equalization control circuit 268...Output matrix 270
A...Right channel output 270B...Left channel output o. Proceedings Supplementary City 11:: 1971 + 71117Fl Special 1: '1 Agency Director n' Manabu Shiga 1 case of beating ('1 last month, 1988 Patent Application No. 11524)
0υ''O1 audio signal processing system, if supplemented, relationship with Iil'l, G Patent applicant 1 agent 5 object of correction ``Drawings'' () As shown in the attached sheet, the official drawings I will submit one copy. Procedures Amendment Book September 3, 1980 Shiga, Commissioner of the Patent Office Year 1 Display of the case 1982 Patent Application No. 113240” 2 Title of the invention Audio signal processing system 3 Person making the amendment Relationship with the case Patent applicant 4 Agent Number (1) Revise the "Scope of Claims" as shown in the attached document. (2) "Left channel signal LJ" on page 7, line 19 to line 3'20 of the specification is corrected to "right channel signal R." (3) On page 8 of the same page, line 3, 2 [correct the right channel signal Rj as "left channel signal L"]. (4) "Left channel" in line 7 of page 10 is corrected to "right channel." (5) Correct "right channel" in line 11 of the same page to "left channel". (6) "Left channel output signal L" in lines 7 to 8 of page 14 of the same page is corrected to "right channel output signal R." (7) Same as above, same page, line 10 ~] ``Connection point 754'' on line 111 is corrected as ``terminal 270Aj.'' (8) Day 14 of the specification, line 11 ~ line 1 and 2 of the specification of"
Correct "left channel output" to "right channel output". (9) Corrected "amplifier 720" in lines 3 and 12 to lines 3 and 13 of the same page as above to read "amplifier 608." ” (1,0) “Furthermore C2” on the 14th line of the same page is corrected to “the non-inverting input terminal is”. (11) Same page - Correct "Gives L signal output. Right channel signal R" in lines 17 to 2 and 18 of the same page to rR (Gives M output. Left channel signal LYJ. 12) Correct "the inverting input C2" on the 2nd and 1st lines of the same page 15 to "the output of the amplifier 766". (13) "Connection output C2" on the 2nd and 6th lines of the same page (14) Specification] - Correct "L and R signals" on page 15, line 11 to "R and L signals". (j5 ) Correct "Table BJ" in lines 1 and 14 of the same page to "Table A". 19 Same as above, page 20, page 3, page 16, line 1, j.
tln (" means nanofarads" 11 p (" means picofarads" is deleted. (18) Same as above λ, page 16, 2nd line r Table BJ is corrected as "Table A". (19) Same as above page 17 (20) in line 1 of the same page, (21) in lines 1-1, page 18 of the same page, and 12 items in lines 15 to 16 of the same page.
Then add "left and right". (22) One OZ attached document drawing (Figure 1, Figure 2, Figure 2) to replace Figure 1 and Figures 2 and 2 submitted at the time of filing with the attached drawings? Claim 1: A signal processing system, comprising: a pair of input terminals for respectively receiving two stereo input signals; matrix means for transmitting a second signal as a function of the horizontal component of the stereo input signal if: connected to the first matrix means for transferring the first signal; First belief 5. a second signal path connected to the first matrix means for transferring the second signal; a second signal path connected within the second signal path; means for amplifying frequency components substantially independently of the vertical components of the stereo input signal to provide a modified second signal; and means for adjusting the first and f52 stereo output signals as a function of the modified second signal. 2. The signal processing system as claimed in claim 1; wherein the stereo input signals represent left and right channel signals L-H, respectively; A signal processing system characterized in that the second signal is determined as a function of L+H. 3. The signal processing system of claim 2, wherein the second matrix means is configured to calculate the first stereo output signal as a function of the sum of the first signal and a modified second signal. A signal processing system comprising adjusting the second stereo output signal as a function of the difference between the first signal and the modified second signal. 4. The signal processing system of claim 3, wherein: the amplified low frequency components of the modified second signal are substantially monophonic, and the second matrix A signal processing system providing stereo output signals, each of the output signals including the amplified low frequency component.

Claims (1)

Claims: In a signal processing system of the type used in audio systems, comprising a device having at least two input terminals for receiving two stereo information signals; a pair of signal paths, each of the signal paths including a system input terminal for receiving a respective one of the input signals, and a system output terminal for coupling the signal path to the device; means for coupling a summation signal representing the sum of the input signals to said signal path of the cow slump; means for amplifying the low frequency component of said summed signal; and means for coupling said amplified low frequency component to said respective signals. a signal processing system comprising: means for amplifying the low frequency components of the audio input signal independently of the vertical components of the human input signal by transmitting the signals to a system output terminal of the input signal;