JP2005346772A - Reproduction device and reproduction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reproduction device in which the operational feeling, the reproduction sound, and the scratch sound close to those of an analog record player are obtained, using a recording medium of a digital recording system. <P>SOLUTION: The reproduction device includes: a motor; a motor driving part for controlling and driving the motor so that the motor is rotated at a prescribed number of revolutions; a turntable rotated by the motor and capable of accelerating, decelerating, stopping, or reversing the rotation by externally applying press force or rotational force; a rotational speed detection part for detecting the rotational speed of the turntable and for outputting rotational speed information; a signal reproduction part for reproducing an audio signal at the reproduction speed corresponding to the rotational speed information, from the recording medium in which the digital audio signal is recorded; and a characteristic changing part for changing the frequency-gain characteristic of the audio signal reproduced according to the rotational speed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a playback device and a playback method for processing and playing back an audio signal.

  An analog record such as an LP record (Long Playing Record) emits a reproduction sound by scanning a needle along a V-shaped groove formed on the surface of the analog record and detecting surface irregularities. Conventionally, a disc jockey (DJ) forcibly changes the rotation speed by applying a rotational force or a pressing force to a rotating turntable by manual operation while reproducing an analog record with an analog record player. A performance method (hereinafter referred to as “DJ play”) that outputs a so-called scratch sound (a sound reproduced from an analog record when the rotation speed of the analog record is rapidly changed from the standard rotation speed) is known.

  With the progress of digital technology, digital recording media such as CD (Compact Disk) and DVD (Digital Video Disk) have become widespread, and the analog record market is shrinking. However, the disk cannot be operated manually by an operator in a digital recording medium that requires a highly accurate optical pickup (or magnetic head) control, and the disk rotates much faster than a record. For example, it is not possible to reproduce a change sound of an audio signal (such as generation of a scratch sound) by reciprocating a digital recording medium in which error-coded data is distributedly recorded. It is impossible to perform the above-mentioned DJ play using a digital recording medium.

  In a playback apparatus using a digital recording system recording medium such as a CD and a DVD on which an audio signal is recorded, a playback apparatus of Conventional Example 1 that enables play similar to DJ play is disclosed in Japanese Patent Laid-Open No. 2002-343026 ( Patent Document 1) and Japanese Patent Application Laid-Open No. 2002-352513 (Patent Document 2).

  The reproducing apparatus of the conventional example 1 has a rotatable jog dial and a pressure detection unit that detects a pressing force applied to the jog dial, rotates the jog dial in a stopped state, and presses the upper surface of the jog dial. Accordingly, the reproduction speed of the audio signal from the recording medium is changed according to the rotation amount of the jog dial and the pressing force detected by the pressure detection unit. This makes it possible to vary the reproduction speed of the audio signal using a recording medium of a digital recording system such as a CD and a DVD as when the rotation speed of the analog record is changed.

  In an analog record, during recording, an audio signal is equalized and recorded with a frequency-gain characteristic (A in FIG. 10) in which the gain is small in the low frequency part and large in the high frequency part. This frequency vs. gain characteristic at the time of recording is called “RIAA characteristic” (see A in FIG. 10), and is standardized by RIAA (Recording Industry Association of America) standard. Further, during reproduction, the audio signal is equalized and reproduced with a frequency-to-gain characteristic (“inverse characteristic of RIAA characteristic”, B in FIG. 10) where the gain is large in the low frequency part and small in the high frequency part. The frequency versus gain characteristic obtained by synthesizing the recording frequency versus gain characteristic and the reproduction frequency versus gain characteristic is flat (the gain is constant with respect to the frequency).

  In the analog record player, when the rotation speed of the analog record is the standard speed (speed at which the recorded signal is reproduced at the original frequency), the sound source is flattened by the recording equalization and the reproduction equalization as described above. It is restored and reproduced as it is with the gain characteristic. However, since the RIAA characteristic has a gain characteristic that varies depending on the frequency, when the rotation speed of the analog record is faster or slower than the standard speed, the frequency versus gain characteristic obtained by combining the RIAA characteristic and the inverse characteristic of the RIAA characteristic is not flat. The audio reproduction signal equalized with the reverse characteristic of the RIAA characteristic has a frequency spectrum different from that of the sound source.

  A specific example will be described. FIGS. 10 to 13 are graphs showing frequency vs. gain characteristics where the horizontal axis represents the logarithm of the frequency (unit Hz) and the vertical axis represents the gain linearly (unit dB. Relative value where the gain at a predetermined frequency is 0 dB). It is. 10A shows the RIAA characteristic. The RIAA characteristic is that when the gain of 1 kHz is 0 dB, the gain is −20 dB at 50 Hz or less, the slope is 6 dB / oct at 50 to 500 Hz, the gain at the frequency of 500 to 2120 Hz is 0 dB, and 2120 Hz or more. At 6 dB / oct.

B of FIG. 10 shows the reverse characteristic of the RIAA characteristic. The inverse characteristics of the RIAA characteristic are: when the gain at 1 kHz is 0 dB, the gain is +20 dB at 50 Hz or less, has a slope of −6 dB / oct at 50 to 500 Hz, and the gain at the frequency of 500 to 2120 Hz is 0 dB. It has a slope of −6 dB / oct at 2120 Hz or higher.
The graphs of A and B in FIG. 10 are vertically symmetric about the horizontal axis of the gain of 0 dB, and the frequency vs. gain characteristic obtained by combining the RIAA characteristic (A in FIG. 10) and its inverse characteristic (B in FIG. 10) is It is flat.

  Consider the case where the rotation speed of an analog record is twice the standard speed. When the rotation speed of the analog record is doubled, the reproduction speed is doubled, and the frequency of the reproduction signal is one octave higher than the frequency of the sound source. For example, in FIG. 10, 50 Hz sound (point P1) of the sound source is 100 Hz when reproduced at twice the rotation speed (point P1 ′), and the frequency vs. gain characteristics change compared to reproduction at standard speed. The minute level is lowered by 6 dB. FIG. 11A shows graphs C and B of frequency vs. gain characteristic change at the time of recording and reproduction when the horizontal axis is the frequency of the reproduction signal (twice the frequency of the sound source). The numbers in parentheses below the horizontal axis indicate the corresponding recording frequency. FIG. 12 shows the frequency vs. gain characteristics (difference between C and B in FIG. 11A) of the reproduction signal output by the analog record player when the reproduction speed is double. In FIG. 12, an audio signal of 500 Hz to 4240 Hz reproduced at twice the speed is emphasized by up to 6 dB compared to an audio signal of 100 Hz to 500 Hz. In FIG. 12, when the reproduction speed is double, the gain is increased by 6 dB.

  When the rotation speed of the analog record is ½ times the standard speed, the reproduction speed is ½ times, and the frequency of the reproduction signal is one octave lower than the frequency of the sound source. For example, in FIG. 10, a sound of 500 Hz (point P2) of the sound source becomes 250 Hz (point P2 ′) when reproduced at a rotation speed of 1/2 times, and frequency vs. gain compared with reproduction at a standard speed. The level of the characteristic change is increased by 6 dB. FIG. 11B shows graphs D and B of frequency vs. gain characteristic change at the time of recording and reproduction when the horizontal axis is the frequency of the reproduction signal (1/2 times the frequency of the sound source). The numbers in parentheses below the horizontal axis indicate the corresponding recording frequency. FIG. 13 shows the frequency vs. gain characteristics (difference between D and B in FIG. 11B) of the reproduction signal output by the analog record player when the reproduction speed is ½. In FIG. 13, audio signals of 25 Hz to 500 Hz and 1060 Hz or higher reproduced at a speed of 1/2 times are emphasized by up to 6 dB as compared with audio signals of 500 Hz to 1060 Hz.

  As described above, when the rotation speed of the analog record changes, the reproduction signal is equalized with a frequency-gain characteristic according to the rotation speed, so that a unique scratch sound different from the sound source is output.

  The playback device of Conventional Example 1 changes the playback speed in response to the operator operating the jog dial. However, since the frequency vs. gain characteristic of the audio signal remains flat (constant) simply by changing the reproduction speed, the reproduction by the reproduction apparatus of the conventional example 1 does not produce an inherent effect like DJ play. The flat plate was not interesting. The playback sound obtained by operating the jog dial using the playback device of the conventional example 1 was completely different from the scratch sound when DJ play was performed using an analog record player. For those who are familiar with DJ play by an analog record player, the reproduced sound output from the reproducing apparatus of the conventional example 1 feels uncomfortable.

  Japanese Laid-Open Patent Publication No. 5-217273 (Patent Document 3) discloses a playback apparatus of Conventional Example 2 that solves the above-described problem and equalizes an audio signal with a frequency-to-gain characteristic based on the RIAA characteristic.

The reproducing apparatus of the conventional example 2 has a rotatable trackball, a rotation speed detection unit that detects the rotation speed of the trackball, and an address that changes at a speed corresponding to the rotation speed of the trackball detected by the rotation speed detection unit. Address control to be output, RIAA recording equalizer for equalizing the reproduction signal from the recording medium with the RIAA characteristic, shift register for temporarily storing the output signal of the recording equalizer, and outputting the signal according to the address output by the address control, and shift register And an RIAA reproduction equalizer for equalizing the audio signal output by the reverse RIAA characteristic. With this configuration, it is possible to output a scratch sound having a sound quality close to that obtained when an analog record player is operated using a recording medium recorded by a digital recording method such as a CD and a DVD.
Japanese Patent Laid-Open No. 2002-343026 JP 2002-352513 A JP-A-5-217273

  However, the playback devices of Conventional Example 1 and Conventional Example 2 perform by operating a jog dial or a trackball that is stopped, which is greatly different from the operation feeling when operating the turntable of an analog record player, It feels uncomfortable for those familiar with the operation of the analog record player.

  Further, in the playback apparatus of the conventional example 2, it is necessary to incorporate each of the equalizers similar to the recording equalizer and the playback equalizer used in the analog record player in the circuit, and the playback processing of the recording medium takes time, and the performance speed is not in time. There is a case. Further, the circuit scale becomes large and the manufacturing cost is high.

  In addition, the analog record player can usually add a predetermined feature to the reproduced sound to be output by changing the needle (cartridge). However, the reproducing apparatuses of the conventional example 1 and the conventional example 2 have various cartridges. Does not reproduce the frequency vs. gain characteristics.

  In view of the above problems, the present invention can be operated by changing the rotation speed of a self-running turntable in a reproducing apparatus and reproducing method for reproducing a recording medium recorded by a digital recording method such as CD and DVD. In addition, by changing the frequency-to-gain characteristic of the reproduction signal based on the RIAA characteristic according to the rotation speed of the turntable by digital signal processing, it is possible to obtain a feeling of operation and a scratch sound closer to an analog record player. It is an object of the present invention to provide a playback device and a playback method.

  In addition, the present invention provides a reproducing apparatus closer to the function of an analog record player, which has a function of changing the frequency vs. gain characteristics of various cartridges of an analog record player when reproducing an audio signal in a recording medium. An object is to provide a reproduction method.

  In order to solve the above problems, the present invention has the following configuration. According to the first aspect of the present invention, a motor, a motor driving unit that controls and drives the motor to rotate at a predetermined number of rotations, and rotationally driven by the motor, and applying a pressing force or a rotational force from the outside. From a turntable that can accelerate or decelerate rotation or stop or reversely rotate, a rotation speed detector that detects a rotation speed of the turntable and outputs rotation speed information, and a recording medium on which a digital audio signal is recorded A signal reproduction unit that reproduces the audio signal at a reproduction speed according to rotation speed information; and a characteristic change unit that changes a frequency-gain characteristic of the audio signal reproduced according to the rotation speed. Is a playback device.

  According to the present invention, when a digital audio signal recorded on a CD (Compact Disc), a DVD (Digital Video Disc), or the like is reproduced, it responds to changes in the rotational speed of a turntable provided separately from the drive mechanism of the recording medium. Then, the signal reproduction unit adjusts the speed at which the audio signal is read from the recording medium, and performs a predetermined frequency-to-gain characteristic changing process according to the rotation speed on the read audio signal, so that the disc jockey (DJ) is as if It is possible to output a reproduced sound as if the rotation speed of the analog record was forcibly changed by hand from a connected speaker or the like.

  In addition, according to the present invention, since the rotation speed can be varied according to the pressing force or the rotational force applied by the user such as a disk jockey (DJ) to the turntable rotating at a predetermined speed, the user feels as if the turntable is an analog It can be handled as if it were a record itself, satisfying users familiar with playing on analog records.

  The configuration of the rotation speed detection unit is arbitrary. For example, a disk with a large number of slits along the outer periphery is arranged coaxially with the turntable, and light passing through the slits is detected by an optical coupler consisting of a light-emitting diode and a phototransistor. The direction and speed of rotation of the turntable are detected by counting the number. Or, for example, a disk-shaped magnet having many magnetic poles along the outer periphery is arranged coaxially with the turntable, and the magnetic field is detected by a magnetic detection element that detects a magnetic field or magnetic flux. The rotation direction and rotation speed of the turntable are detected by counting the number of pulses.

  Preferably, the following configuration is further adopted. The size of the turntable is the same as the turntable of the analog record player. That is, the diameter of the turntable is set to be larger than the diameter of the analog record. The rotation speed of the turntable is the same as the rotation speed of the turntable of the analog record player (typically 45 rpm or 33+ (1/3) rpm). The motor torque of the turntable is set to be the same as that of the turntable of the analog record player. As a result, the user can obtain an operational feeling closer to that of an analog record player.

The recording medium on which the digital audio signal is recorded is arbitrary. For example, CD, DVD, MO, MD and other playback-only, write-once or rewritable and replaceable light, magneto-optical or magnetic disk, SD card, semiconductor memory such as memory stick, hard disk that cannot be replaced, music taken from tuners RAM etc. which memorize etc.
The playback device may have a recording function.

  The invention according to claim 2 is the reproducing apparatus according to claim 1, wherein the characteristic changing unit emphasizes or weakens a specific frequency band of the reproduced audio signal.

  According to the present invention, for example, in a process of equalizing an audio signal read from a recording medium such as a CD (Compact Disc), a user can turn the gain of a predetermined frequency band in accordance with the rotation speed information to increase or decrease the gain. A specific reproduction sound (for example, a scratch sound) can be output in accordance with the operation of.

  The invention according to claim 3 is the reproducing apparatus according to claim 2, wherein the specific frequency band is calculated from the rotation speed.

  According to the present invention, when the turntable is scratched (moved quickly back and forth in the rotation direction) by changing the frequency band in which the gain is increased or decreased according to the rotation speed of the turntable, it is as if the analog record was scratched. The reproduction sound (scratch sound) as described above can be output, and the user familiar with the reproduction sound and scratch sound in the analog record can be satisfied.

  According to a fourth aspect of the present invention, the signal reproduction unit outputs the audio signal at a reproduction speed obtained by multiplying a ratio of a current rotation speed of the turntable to a rotation speed at no load and a recording speed. The audio signal is output by changing the frequency by the ratio from the time of recording, and the characteristic changing unit is not flat and the frequency vs. gain characteristic obtained by synthesizing two characteristics is flat. At least one of the frequency-to-gain characteristic and the second frequency-to-gain characteristic is stored, the audio signal is equalized with the first frequency-to-gain characteristic at the time of recording, and the frequency at the time of reproduction is higher than that at the time of recording. When the audio signal changed by the ratio is equalized with the second frequency-to-gain characteristic, the recording and reproduction equalization received by the reproduced audio signal is synthesized. The same characteristics as the frequency vs. gain characteristics, changes the frequency versus gain characteristic of the reproduced the audio signal, it is a reproduction apparatus according to claim 1, wherein the.

When the user scratches the turntable using the playback device of the present invention (moves quickly back and forth in the direction of rotation), it can output a playback sound (scratch sound) as if the analog record was scratched, It is possible to satisfy a user who is familiar with the reproduction sound and scratch sound in the analog record.
Preferably, a frequency-to-gain characteristic obtained by synthesizing equalization of recording and reproduction received by the reproduced audio signal is derived based on a change in the number of rotations, and the reproduced signal is equalized using the synthesized frequency-to-gain characteristic. Thereby, with one equalizing filter, an effect equivalent to DJ play using an analog record player can be produced.

  According to a fifth aspect of the present invention, the signal reproduction unit outputs the audio signal to the recording medium at a reproduction speed obtained by multiplying a recording speed by a ratio of a current rotation speed of the turntable to a rotation speed at no load. The audio signal is interpolated and read out and output so that the frequency of the audio signal at the time of reproduction is not different from that at the time of recording, and the characteristic changing unit is not flat and combines two characteristics. At least one of a first frequency-gain characteristic and a second frequency-gain characteristic having a flat frequency-gain characteristic is stored, and an audio signal is equalized with the first frequency-gain characteristic during recording. In addition, when the audio signal whose frequency has changed by the ratio during recording is equalized with the second frequency-to-gain characteristic, the reproduced audio signal is received. In recording and reproducing the same characteristics as the frequency vs. gain characteristic of the equalizing and combining of, changing the frequency vs. gain characteristic of the reproduced the audio signal, it is a reproduction apparatus according to claim 1, characterized in.

When a digital signal is read from a recording medium with a clock corresponding to a change in the number of rotations, the frequency generally changes by a change rate of the number of rotations from when an audio signal is recorded (the invention according to claim 4). In the present invention, the audio signal read from the recording medium with the clock corresponding to the change in the rotational speed is returned to the recording frequency by interpolation.
Conventionally, when the user scratches the turntable using the playback apparatus of the present invention (moves quickly back and forth in the direction of rotation), the frequency of the playback signal is the same as that during recording, and the equalizing characteristics change according to the DJ play. This makes it possible to perform a new DJ play that was not possible with the analog record player.

  Preferably, a frequency vs. gain characteristic obtained by synthesizing equalization of recording and reproduction received by the reproduced audio signal based on a change in the number of rotations is derived by calculation or the like, and the reproduced signal is equalized by the synthesized frequency vs. gain characteristic. . Thereby, the effect of DJ play can be produced with one equalizing filter.

  According to a sixth aspect of the present invention, the first frequency versus gain characteristic is an equalizing characteristic of RIAA (Recording Industry Association of America) standard, and the second frequency versus gain characteristic is an equalizing characteristic of RIAA standard. 6. The reproducing apparatus according to claim 4, wherein the reproducing apparatus is an inverse characteristic of the characteristic.

  The present invention can output a reproduction sound as if it was reproduced in an analog record by adjusting the gain in a predetermined frequency band of the audio signal based on RIAA which is an analog record standard. It is intended to satisfy users who are familiar with the playback sound of analog records.

  According to the seventh aspect of the present invention, the characteristic changing unit stores one or a plurality of effect types having different frequency versus gain characteristics, and the reproduced audio signal according to the effect type selected by the operator The reproduction apparatus according to any one of claims 1 to 6, wherein the frequency vs. gain characteristic is changed.

  The present invention stores, for example, a plurality of previously prepared effect types that reproduce the characteristics of various needles (cartridges) of an analog record player, and allows the user to select a desired effect type. By selecting the effect type, the user can obtain an effect as if the cartridge of the analog record player was replaced, and can give variations to the reproduced sound.

  The invention according to claim 8 further includes a storage unit that stores a table in which the storage medium identification information derived from the unique information of the storage medium is associated with the effect type, and the storage medium is replaceable. The characteristic changing unit derives storage medium identification information from unique information of the storage medium for reproducing an audio signal, reads an effect type from the table based on the storage medium identification information, and based on the effect type The reproduction apparatus according to claim 7, wherein the reproduced audio signal is changed.

  According to the present invention, an identification ID for identifying a recording medium is generated by performing a predetermined calculation using unique information (for example, track information) of the recording medium. Further, by storing the effect type selected in association with the identification ID in the storage unit, when the same recording medium is reproduced next time, the identification ID is searched from the storage information of the storage unit, and the same as the previous time. The effect type can be read and selected. In the reproducing apparatus of the present invention, it is not necessary to set the effect type when the recording medium reproduced in the past is reproduced next time.

  According to the ninth aspect of the present invention, the table is associated with the recording medium identification information, and the last time the effect type described in the table is read in order to change the audio signal reproduced from the storage medium. Or an index value indicating the number of times the effect type described in the table is read in order to change an audio signal reproduced from a storage medium other than the storage medium from the last time to the present, and stored in the storage unit When the recording area for writing new information is insufficient, based on the index value, the oldest recording medium identification information or the recording medium identification information with the largest number of times is searched, and the recording medium 9. The reproducing apparatus according to claim 8, wherein new information is written in a recording area of identification information.

  In a playback device with a limited storage capacity of the storage unit, there may be no storage area for newly storing the recording medium identification information and the effect type applied when the audio signal is played back from the storage medium. . In such a case, the reproducing apparatus of the present invention discards information relating to the recording medium that has not been accessed for the longest time, and records information relating to a new recording medium in the storage area in which the information has been stored. In order to be able to detect a recording medium that has not been used for the longest time, the playback apparatus of the present invention stores an index value (the name is arbitrary) in the table. By referring to the index value, it is possible to overwrite the oldest recording medium information.

  For example, each time a recording medium is recognized, the index value associated with the recording medium identification information representing the recording medium is reset to an initial value (for example, “0”), and other index values are set to predetermined values (for example, “ 1 ") is added. This indicates that the larger the index value, the older the access to the corresponding storage medium.

  The present invention further has the effect of realizing a reproduction method that is substantially the same as the above reproduction apparatus and produces the same effect.

  The playback apparatus and playback method according to the present invention provide a pressing force or rotational force applied to a turntable by a user such as a disc jockey (DJ) when playing back a digital audio signal recorded on a recording medium such as a CD or DVD. By changing and outputting the frequency vs. gain characteristics of the audio signal according to the change in the rotation speed due to the sound, it is possible to obtain an operational feeling and playback sound as if the rotation speed of the analog record was forcibly changed by hand. There is an advantageous effect of being able to.

  The playback apparatus and playback method according to the present invention performs a characteristic change process according to the rotation speed of the turntable on the audio signal, so that when the turntable is scratched (moved quickly back and forth in the rotation direction), it is as if an analog record is recorded. There is an advantageous effect that the reproduced sound can be output as if it were scratched. According to the present invention, it is possible to achieve an advantageous effect that it is possible to realize a playback apparatus and a playback method that satisfy users who are familiar with performance, playback sound, and scratch sound on an analog record player.

  Furthermore, the playback apparatus and playback method of the present invention perform frequency-to-gain characteristic change processing based on the RIAA characteristics, which are analog record standards, and the frequency-to-gain characteristics of various needles (cartridges) of analog records. As a result, it is possible to output a reproduction sound and a scratch sound that are closer to an analog record player, and to satisfy the user with various variations.

  Furthermore, in the playback apparatus and playback method of the present invention, the recording medium identification information unique to the storage medium is generated using the unique information read from the storage medium (for example, track information), and the effect type set last is selected. When the reproducing apparatus recognizes a recording medium having the same recording medium identification information next time and stores it in association with the recording medium identification information, the previous effect type is applied to the reproduction signal. Thereby, there is an advantageous effect that it is not necessary to set the effect type when the recording medium reproduced in the past is reproduced next.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments that specifically show the best mode for carrying out the present invention will be described below with reference to the drawings.

Embodiment 1
The playback apparatus and playback method according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing an outline of the configuration of a playback apparatus according to Embodiment 1 of the present invention. The playback apparatus according to the first embodiment is a CD player. In FIG. 1, 1 is an operation input display unit, 2 is a reproduction unit, 3 is a turntable rotation detection unit, and 4 is an audio output unit (speaker).

  The operation input display unit 1 includes an operation input unit 5 and a display unit 6. The operation input unit 5 includes a play key, a stop key, an effect valid / invalid switch key for switching effect validity / invalidity, and an effect type switch key (not shown) for the user to select an effect type. . When the effect is valid, the reproduced audio signal is changed in accordance with the characteristics described later (DJ play valid) according to the change in the rotational speed of the turntable 17. When the effect is invalid, the audio signal is not changed regardless of the change in the rotational speed of the turntable 17 (DJ play is invalid). The display unit 6 is a liquid crystal display panel for displaying the reproduction status of the recording medium, the validity / invalidity of the effect, and the number / name / feature of the selected effect type. Each key of the operation input unit 5 may be pressed and input, or may be input by contact, or may be integrated with the display unit 6 such as a touch panel. The characteristics of the effect type are, for example, a graph of frequency vs. gain characteristics, or an effect that is displayed in words. If the effect is set to invalid, nothing is displayed or it is invalid. Display characters, etc.

  The audio output unit 4 is an output device or a speaker that outputs an audio signal input from the reproduction unit. The audio output unit 4 may be connected to the outside of the playback device or may be built in.

  The turntable rotation detection unit 3 includes a turntable 17, a first motor 18, a first motor drive unit 19, and a rotation speed detection unit 20. The first motor driving unit 19 receives a command from the control unit 11 of the reproducing unit 2 and rotates or stops the first motor 18 at a constant rotational speed.

  FIG. 2 is a schematic plan view and a front view of the turntable 17. The turntable 17 is attached to the upper part of the housing of the playback device. The turntable 17 has a slip surface 25. A user such as a disc jockey (DJ) rotates at a constant speed when there is no load (when the user is not operating the slip surface 25) by operating the slip surface 25 by applying a pressing force or rotational force. It is possible to accelerate or decelerate, stop, or reversely rotate the turntable 17 that is rotating.

  In the first embodiment, the size of the turntable is the same as the turntable of the analog record player. That is, the diameter of the turntable is set to be slightly larger than the diameter of the analog record. The rotation speed of the turntable is the same as the rotation speed of the turntable of the analog record player (typically 45 rpm or 33+ (1/3) rpm). 45 rpm and 33+ (1/3) rpm are switched by a switch (not shown) of the operation input unit 5. The rotational torque of the turntable 17 is set to be the same as the rotational torque of the turntable of the analog record player.

  Next, the rotation speed detection unit 20 will be described. FIG. 3 shows a block diagram of a detailed configuration of the rotation speed detector 20. In FIG. 3, the rotation speed detection unit 20 includes an optical sensor 30 and a pulse counter 31. On the other hand, a disk having a large number of slits along the outer periphery is disposed coaxially with the turntable 17 (not shown). The optical sensor 30 is installed at a position where the rotation of the disk rotating together with the turntable 17 can be detected, and is an optical coupler comprising two sets of light emitting diodes and phototransistors disposed at positions 90 degrees out of phase with each other. Have Each optical coupler detects light passing through the slit 23 of the turntable 17. The phototransistor of the optical coupler is turned on when a light amount of a predetermined amount or more is detected, and turned off in other cases. Two sets of optical couplers constituting the optical sensor 30 output two-phase pulse signals.

  The pulse counter 31 counts rising edges of one of the input two-phase pulse signals every predetermined time (for example, 0.1 second). In addition, by using the D flip-flop, the other one-phase pulse signal is latched at the rising edge of the one-phase pulse signal to determine whether the turntable 17 is rotating in the positive direction or the negative direction. can do. The pulse counter 31 informs the control unit 11 of the reproducing unit 2 of the number of pulses counted every time a predetermined time elapses and information on whether the rotation is in the positive direction or the negative direction (collectively referred to as “rotational speed information”). Output.

  The configuration of the rotation speed detection unit 20 is not limited to the configuration of the first embodiment and is arbitrary. For example, a disk-shaped magnet having many magnetic poles magnetized along the outer periphery is disposed coaxially with the turntable 17, and the movement of the magnetic pole is detected by a magnetic detection element that detects two magnetic fields or magnetic fluxes for a predetermined time. The configuration may be such that the rotation direction and the rotation speed of the turntable are detected by counting the number of pulses.

  The reproducing unit 2 includes a second motor 8, a second motor driving unit 9, an optical pickup 22, a signal reproducing unit 10, a control unit 11, a characteristic changing unit 12, a storage unit 16, a traverse motor driving unit 23, and a traverse motor. 24.

  The control unit 11 controls the entire playback device. The control unit 11 inputs various commands from the operation input unit 5, inputs rotational speed information from the turntable rotation detection unit 3, outputs an ON / OFF command for the first motor drive unit 19, and displays the display unit 6. A display command is sent to and the playback unit 2 is controlled.

  When the playback key of the operation input unit 5 is pressed with the recording medium 7 mounted, the control unit 11 outputs an instruction to start rotation to the second motor control unit 9 and the effect is valid. For example, an instruction to start rotation is output to the first motor control unit 19, and a reading speed control signal corresponding to the tempo signal is output to the signal reproduction unit 10. When the reproduction key is pressed again during reproduction, the control unit 11 outputs an instruction to stop the audio signal reading operation to the signal reproduction unit 10.

  When the stop key is pressed, the control unit 11 outputs an instruction to stop the rotation to the first motor control unit 19 and the second motor control unit 9. When the eject key is pressed, the control unit 11 instructs a mounting mechanism drive unit (not shown) to eject the recording medium 7 to the outside of the playback device.

  When the effect valid / invalid key is pressed, the control unit 11 switches the effect valid / invalid (DJ play valid / invalid). When the DJ play is valid, the reproducing unit 2 changes the reproduction speed of the audio signal read from the recording medium 7 in accordance with the change in the rotation speed of the turntable 17 and changes the reproduced audio signal with the characteristics described later. To control. At the time of reproduction, when the DJ play is invalid, the control unit 11 reads out the audio signal from the recording medium 7 at a constant reproduction speed regardless of the change in the rotation speed of the turntable 17, and has a flat (constant) frequency versus gain characteristic. The reproduction unit 2 is controlled so as to amplify and output the audio signal.

The control unit 11 includes a tempo calculation unit 21 and an identification ID calculation unit 15. In the first embodiment, the control unit 11 is a microcomputer, and the functions of the tempo calculation unit 21 and the identification ID calculation unit 15 are executed by a program.
The tempo calculation unit 21 generates a tempo signal based on the rotation speed information input from the rotation speed detection unit 20. The tempo signal is obtained by dividing the current number of pulses input per unit time by the number of pulses per unit time at the standard rotation speed of the turntable (the number of rotations under no load). It is a signal with information on rotation or negative rotation.

  The identification ID calculation unit 15 of the control unit 11 inputs the track information of the music (track) recorded on the recording medium from the signal reproduction unit 10, and executes a predetermined calculation using the number of seconds of the performance time of each track. Thus, an identification ID is generated. Since it is very unlikely that the number of seconds in each track will be the same in two different recording media, the identification ID can be regarded as ID information unique to the recording medium.

  When the effect type switching key (operation input unit 5) is pressed, the control unit 11 switches the effect type in the range of type 1 to type 8. The effect type switching key has a plus key for selecting the types assigned to 1 to 8 in ascending order and a minus key for selecting in descending order. When the plus key is pressed, it switches to the number type one level above. Alternatively, the effect type switching key may have only one key and cyclically select type 1 to type 8.

  The storage unit 16 stores the identification ID representing the recording medium 7 recognized in the past, the validity / invalidity of the effect, the effect type last set for the reproduction signal read from the recording medium 7, and the index value. The associated table is stored. FIG. 9 shows an example of the table.

  The storage capacity of the storage unit 16 is limited, and recording medium information of a predetermined amount or more cannot be stored. When there is no more free recording area in the storage unit 16, it is preferable to discard the oldest recording medium information and overwrite the new recording medium information on the recording area in which the recording medium information is recorded. Each time the controller 11 recognizes the identification ID of the attached storage medium 7, it checks whether there is the same identification ID in the table, and if there is the same identification ID, the index value corresponding to that identification ID. Is set to “0”, and “1” is added to the index values corresponding to other identification IDs. Thereby, it can be determined that the recording medium information with the maximum index value has the oldest access.

Alternatively, the last date and time when the audio signal is reproduced from the storage medium and the effect type described in the table is read may be written in the table.
If there is no identification ID identical to the identification ID of the storage medium 7 mounted on the table, the recording medium information with the oldest access is discarded, and the new recording medium information is overwritten in the recording area where the recording medium information is recorded. To do.

  The control unit 11 outputs an effect valid / invalid signal, an effect type signal, and a tempo signal to the characteristic changing unit 12.

  The second motor 8 is a spindle motor that rotates a detachable recording medium 7 (for example, a CD). The second motor drive unit 9 starts or stops the rotation of the second motor 8 according to a command from the control unit 11. The second motor drive unit 9 can change the rotation speed of the second motor 8 (the reproduction speed of the audio signal read from the recording medium 7) in accordance with a command from the control unit 11.

  The traverse motor 24 is a linear motor that moves the optical pickup 22 in the radial direction of the CD. The traverse motor drive unit 23 starts or stops driving the traverse motor 24 in accordance with a command from the control unit 11. The traverse motor drive unit 23 can change the moving speed (the reproduction speed of the audio signal read from the recording medium 7) according to the command from the control unit 11.

  The optical pickup 22 reads an audio signal and track information from the recording medium 7. The signal reproducing unit 10 performs error correction decoding, decompressing and outputting the error correction encoded and compressed audio signal read by the optical pickup 22, and outputs the error corrected track information. The signal reproducing unit 10 outputs the decoded and expanded audio signal to the characteristic changing unit 12 and the track information to the control unit 11. In addition, it is possible to read the audio signal at an arbitrary speed in the forward direction and the reverse direction upon receiving a read speed control signal from the control unit 11 (so-called forward reproduction and reverse reproduction), and the audio signal read speed. Can be changed or stopped. As is well known, even during reverse playback, the rotation direction of the second motor 8 does not reverse, and the signal playback unit 10 performs an internal data process as if the read audio signal is an analog record. A continuous reverse playback sound is output as when the is rotated in reverse.

  When the DJ play is set to be effective and played back, the signal playback unit 10 calculates the ratio of the current rotational speed of the turntable 17 to the rotational speed at the time of no load, that is, the recording speed and the recording speed. The audio signal is reproduced from the recording medium 7 at the multiplied reproduction speed. The audio signal is regenerated at a clock speed obtained by multiplying the ratio of the current rotation speed of the turntable 17 to the rotation speed at no load and the clock speed at the time of recording. Accordingly, the frequency of the reproduced audio signal changes from the original sound (audio signal at the time of recording) by the ratio of the current rotational speed of the turntable 17 to the rotational speed at no load.

  When reproduction is performed with the DJ play set to invalid, the signal reproduction unit 10 reads out and outputs an audio signal from the recording medium 7 at a constant reproduction speed regardless of a change in the rotational speed of the turntable 17.

  The characteristic changing unit 12 includes a RIAA characteristic processing unit 13 and an effect processing unit 14. The RIAA characteristic processing unit 13 receives a tempo signal and an effect valid / invalid signal from the control unit 11 and an audio signal from the signal reproduction unit 10. The RIAA characteristic processing unit 13 performs a characteristic changing process based on the RIAA standard on the audio signal in accordance with each signal input from the control unit 11 and outputs the result to the effect processing unit 14. The effect processing unit 14 receives an effect enable / disable signal and an effect type signal from the control unit 11, and receives an audio signal from the RIAA characteristic processing unit 13. The effect processing unit 14 performs a characteristic change process corresponding to the selected effect type on the audio signal according to each signal input from the control unit 11, and outputs it to the audio output unit 4.

  The effect valid / invalid signal is a signal indicating whether the effect is valid or invalid. The type selection signal is a signal indicating any one of eight effect types from type 1 to type 8. Detailed operations of the RIAA characteristic processing unit 13 and the effect processing unit 14 will be described later.

  When the DJ play is set to be effective and played back, the control unit 11 calculates a playback speed proportional to the generated tempo signal, and outputs a read speed control signal instructing the calculated read speed to the signal playback unit 10. In general, the second motor 8 and the traverse motor 24 cannot be driven in accordance with the DJ play. The signal reproduction unit 10 has a buffer memory (RAM), and reproduces and outputs an audio signal previously stored in the buffer memory to some extent in accordance with the reading speed control signal (according to the DJ play). The control unit 11 sends drive commands to the second motor drive unit 9 and the traverse motor drive unit 23 so that the buffer memory (RAM) does not become empty.

  Next, the configuration and detailed operation of the RIAA characteristic processing unit 13 and the effect processing unit 14 of the characteristic changing unit 12 will be described with reference to FIGS.

  FIG. 4 is a block diagram showing a detailed configuration of the RIAA characteristic processing unit 13. In FIG. 4, the RIAA characteristic processing unit 13 includes a first coefficient determining unit 41, a first coefficient setting unit 42, a first digital filter 43, a second digital filter 44, a third digital filter 45, and an output. A gain adjustment unit 46 is provided.

  The first coefficient determination unit 41 receives the effect valid / invalid signal and the tempo signal from the control unit 11, and calculates coefficient information indicating the coefficient values of the digital filters 43 to 45 and the coefficient value of the output gain adjustment unit 46. And output to the first coefficient setting unit 42. When the coefficient information input from the first coefficient determination unit 41 changes, the first coefficient setting unit 42 rewrites the coefficients of the digital filters 43 to 45 and the output gain adjustment unit 46 according to the coefficient information.

  When the input effect valid / invalid signal is invalid, the first coefficient determination unit 41 has the same input signal and output signal in each digital filter 43 to 45 and the output gain adjustment unit 46 regardless of the tempo signal (through). ) Is output. When the effect valid / invalid signal is valid, every time the value of the input tempo signal is changed, a predetermined calculation is performed according to the tempo signal, and each coefficient information is determined and output. This calculation is programmed in advance so as to have a frequency versus gain characteristic similar to a scratch sound that is output from an analog record player when the rotation speed of the analog record is changed.

In the first embodiment, the first coefficient determination unit 41 has a first frequency-gain characteristic that is an equalizing characteristic of the RIAA (Recording Industry Association of America) standard and an inverse characteristic of the equalizing characteristic of the RIAA standard. A second frequency vs. gain characteristic is stored. Only one of them may be stored, and then the other may be derived by calculation.
The first frequency versus gain characteristic and the second frequency versus gain characteristic are not flat, and the frequency versus gain characteristic obtained by combining the two characteristics is flat.

  The first coefficient determining unit 41 equalizes the audio signal with the first frequency vs. gain characteristic at the time of recording and further compares the current rotation speed of the turntable 17 with respect to the rotation speed when the frequency is no load compared to the recording time during reproduction. A coefficient that realizes the same characteristics as the frequency-to-gain characteristics obtained by synthesizing the recording and playback equalization received by the reproduced audio signal when the audio signal changed by the ratio is equalized with the second frequency-to-gain characteristic. Calculate information. The RIAA characteristic processing unit 13 performs a characteristic change process of the audio signal with the frequency versus gain characteristic. The frequency vs. gain characteristic obtained by synthesizing the recording and reproduction equalization received by the reproduced audio signal is the characteristic shown in FIGS. 12 and 13, for example.

  When the tempo signal indicates a standard rotation speed, the digital filters 43 to 45 and the output gain adjustment unit 46 output coefficient information that is “through”.

  FIG. 5 is a diagram illustrating a specific configuration of each of the digital filters 43 to 45 and each of the digital filters 73 to 75 in FIG. 7 described later. In FIG. 5, each of the digital filters 43 to 45 and the digital filters 73 to 75 has three amplifiers, and each amplifier has a variable coefficient. By changing each coefficient according to the coefficient information input from the first coefficient setting unit 42 (or the second coefficient setting unit 72 described later), the filtering characteristic (frequency versus gain characteristic) of the input audio signal is changed. To do.

  FIG. 6 is a diagram illustrating a specific configuration of the output gain adjustment unit 46. In FIG. 6, the output gain adjustment unit 46 has an amplifier having a variable coefficient (amplification factor). By changing the coefficient, the gain is adjusted in all frequency bands with respect to the input signal.

  Here, as an example of the operation in each of the digital filters 43 to 45 and the output gain adjustment unit 46, a case where the rotation speed of the turntable 17 is twice the standard speed will be described as an example.

  First, as described in the background art, in the analog record player, when the rotation speed of the analog record is double, the frequency vs. gain characteristic obtained by synthesizing the recording and reproduction equalizing characteristics for processing the reproduction signal is shown in FIG. The characteristics are as follows. The RIAA characteristic processing unit 13 sets the three digital filters 43 to 45 as follows, for example, and realizes the frequency versus gain characteristic shown in FIG.

  The first digital filter 43 is set as a low-pass filter. The frequency vs. gain characteristic of the first digital filter 43 is such that the gain is 0 dB below 50 Hz, the gain decreases linearly at −6 dB / oct from 50 Hz to 100 Hz, and becomes constant at −6 dB above 100 Hz. Is set.

  The second digital filter 44 is set as a high-pass filter. The frequency versus gain characteristic of the second digital filter 44 is set so that the gain is 0 dB below 500 Hz, the gain increases linearly at 6 dB / oct from 500 Hz to 1000 Hz, and constant at 6 dB above 1000 Hz. The

The third digital filter 45 is set as a low-pass filter. The frequency versus gain characteristic of the third digital filter 45 is such that the gain is 0 dB below 2120 Hz, the gain decreases linearly at −6 dB / oct from 2120 Hz to 4240 Hz, and becomes constant at −6 dB above 4240 Hz. Is set.
The RIAA characteristic processing unit 13 subjects the input audio signal to filtering processing by the three digital filters 43 to 45, and then outputs it to the output gain adjustment unit 46.

  The output gain adjusting unit 46 outputs the audio signal input from the third digital filter 45 by changing the frequency-to-gain characteristic so that the gain is increased by 6 dB for all frequency bands.

  The characteristics obtained by synthesizing the frequency-to-gain characteristics of the digital filters 43 to 45 and the output gain adjusting unit 46 in FIG. 4 coincide with the frequency-to-gain characteristics when the rotation speed is doubled by the analog record player shown in FIG. To do. When the rotation speed of the turntable is twice the standard speed, since the gain of the output gain adjustment unit 46 is set to 6 dB, the gain shown in FIG. 12 is a combination of the RIAA recording equalizer and the reproduction equalizer. 6 dB higher than the value.

  Similarly, when the rotation speed of the turntable is ½ times the standard speed, the analog record shown in FIG. 13 is set by setting appropriate coefficients in the digital filters 43 to 45 and the output gain adjustment unit 46. The same frequency-gain characteristics as the frequency-gain characteristics when the rotation speed is halved by the player are realized. When the rotation speed of the turntable is ½ times the standard speed, since the gain of the output gain adjustment unit 46 is set to −6 dB, the gain shown in FIG. 13 is the recording equalizer and reproduction equalizer of RIAA. Is 6 dB lower than the synthesized value.

  That is, the playback apparatus of the present invention realizes the processing performed by the recording equalizer and the playback equalizer in the playback apparatus of the conventional example 2 by changing the coefficients of a set of digital filters. Thus, the processing time is short when the filter is realized by software, and the cost is low when the filter is realized by hardware.

Next, the operation of the effect processing unit 14 will be described. FIG. 7 is a block diagram showing a detailed configuration of the effect processing unit 14. The effect processing unit 14 includes a second coefficient determination unit 71, a second coefficient setting unit 72, a fourth digital filter 73, a fifth digital filter 74, a sixth digital filter 75, and a coefficient storage unit 76. .
The effect processing unit 14 receives an audio signal after performing appropriate RIAA characteristic processing from the RIAA characteristic processing unit 13, and effects type signal and effect corresponding to the input by the input key of the operation input unit 5 from the control unit 11. Input valid / invalid signal.

  The second coefficient determination unit 71 receives the effect valid / invalid signal and the effect type from the control unit 11, and outputs coefficient information of coefficient values of the digital filters 73 to 75 to the second coefficient setting unit 72.

  When the input effect valid / invalid signal indicates invalidity, the effect processing unit 14 outputs the audio signal as it is. The second coefficient determination unit 71 outputs coefficient information that is through in each of the digital filters 73 to 75 to the second coefficient setting unit 72 regardless of the input effect type. When the input effect valid / invalid signal indicates validity, the effect processing unit 14 performs effect processing on the audio signal according to the input effect type signal and outputs the result. The second coefficient determination unit 71 reads the coefficient information corresponding to the input effect type from the coefficient storage unit 76 and outputs it to the second coefficient setting unit 72. Each time the coefficient information input from the second coefficient determination unit 71 changes, the second coefficient setting unit 72 rewrites the coefficients of the digital filters 73 to 75 according to the coefficient information.

The coefficient storage unit 76 stores the coefficients of the digital filters 73 to 75 for realizing the effect types 1 to 8. An example of storage information stored in the coefficient storage unit 76 is shown in FIG. In FIG. 8, coefficient information 80 of effect types 1 to 8 in the fourth digital filter 73 and coefficient information 81 of effect types 1 to 8 in the fifth digital filter 74 are shown. When the coefficients of the digital filters 73 to 75 are changed, the respective frequency versus gain characteristics change accordingly.
The digital filters 73 to 75 have the configuration shown in FIG.

  When Type 1 is selected, coefficient information that is “through” in each of the digital filters 73 to 75 is output to the second coefficient setting unit 72. That is, the reproduction signal output from the digital filter 75 is a reproduction signal that has undergone only the RIAA characteristic change processing in the RIAA characteristic processing unit 13. Type 2 to type 8 reproduce frequency vs. gain characteristics by various analog record needles (cartridges) and analog record arms that are commercially available. For example, WIDE RANGE, which broadens the playback signal, is generally called WIDE RANGE. Effects, etc.

  Next, the operation of the reproducing apparatus of the present invention configured as described above will be described with reference to FIG. 14, FIG. 16, and FIG.

  FIG. 14 is a flowchart showing a playback method when DJ play is enabled in the playback apparatus according to the first embodiment of the present invention. First, the first motor 18 is rotationally driven to rotate the turntable 17 (S1401). Next, the rotation speed detector 20 detects the rotation speed of the turntable 17 (S1402). The signal reproduction unit 10 reads the audio signal from the recording medium 7 at a speed corresponding to the rotation speed of the turntable 17 (S1403). The RIAA characteristic processing unit 13 calculates a frequency versus gain characteristic based on the rotation speed (S1404), and changes (processes) the audio signal with the calculated frequency versus gain characteristic (S1405).

  Next, the effect processing unit 14 determines whether or not the effect is valid and one of the effect types of type 2 to type 8 is selected (S1406). If the effect is invalid or the effect type of type 1 is selected (if the effect type of type 2 to type 8 is not selected), the effect processing unit 14 outputs the input audio signal through. The process proceeds to S1408. If the effect is valid and one of the effect types from type 2 to type 8 is selected, the process proceeds to S1407. The effect processing unit 14 changes (processes) the audio signal with a coefficient corresponding to the selected effect type to generate the selected effect (S1407). An audio signal is output (S1408).

  The audio signal processing method will be described with reference to FIGS. FIG. 16 is a flowchart for explaining the effect setting method of the playback apparatus according to the first embodiment of the present invention. First, rotation of the second motor is started (S1601), and the recording medium (CD in the first embodiment) 7 is rotated. The track information is read from the recording medium 7 (S1602). The identification ID calculation unit 15 calculates an identification ID from the read track information (S1603), and searches the table of the storage unit 16 for the same identification ID (S1604).

Next, it is checked whether or not the same identification ID as the calculated identification ID is found in the table in the storage unit 16 (S1605). If an identification ID identical to the calculated identification ID is found, the effect valid / invalid and effect type are set in the effect processing unit 14 according to the storage information described in the table (S1606), and the process proceeds to S1609. When the same identification ID as the identification ID calculated in the table in the storage unit 16 is not found, the effect type is set to type 1 with the effect valid / invalid set to invalid (S1607). The identification ID of the mounted CD, the validity / invalidity of the effect, and the effect type are additionally stored as new data in the table of the storage unit 16 (S1608).
In S1608, if the storage capacity of the table is insufficient, the storage information having the oldest access in the table is searched based on the index value, discarded, and new storage information is overwritten and recorded in the recording area. .
The process proceeds to S1609.

  Next, the index value of the table corresponding to the identification ID of the storage medium 7 inserted in the playback device is set to “0”, and “1” is added to all index values corresponding to other identification IDs in the table. (S1609).

  Next, it is determined whether or not the operator has instructed to change the setting of the effect processing unit 14 (S1610). If the operator has not instructed to change the setting of the effect processing unit 14, the process proceeds to S1701 in FIG. If the operator has instructed to change the setting of the effect processing unit 14, the control unit 11 changes the setting of the effect processing unit 14 (S1611). The control unit 11 changes the storage information of the table in the storage unit 16 (S1612). It progresses to S1701 of FIG.

  The details of the audio signal processing method by the characteristic changing unit 12 will be described with reference to FIG. FIG. 17 is a flowchart for explaining the audio signal processing method by the characteristic changing unit 12 according to the first embodiment of the present invention. First, rotation of the first motor is started (S1701). The signal reproducing unit 10 reads an audio signal from the recording medium 7 (S1702).

  Next, it is checked whether or not the effect is invalid (S1703). If the effect is invalid, the audio signal read from the recording medium 7 is output as it is (S1704). If it is not invalid (if valid), the RIAA characteristic processing unit 13 executes frequency-gain characteristic change processing based on the RIAA characteristic on the reproduced audio signal according to the rotational speed of the turntable 17 (S1704).

  Further, it is checked whether or not the effect type is type 1 (S1705). If it is type 1, an audio signal is output as it is (S1707). If it is not Type 1, frequency-to-gain characteristic changing processing based on one of the selected type 2 to type 8 is executed (S1706), and an audio signal is output (S1707).

<< Embodiment 2 >>
The playback device and playback method of the second embodiment will be described with reference to FIG. The playback apparatus and playback method of the second embodiment are different from the first embodiment only in the playback method when DJ play is valid. In other respects, the playback apparatus and playback method of the second embodiment are the same as those of the first embodiment.
A playback method when the DJ play of the present invention is valid will be described. FIG. 15 is a flowchart showing a playback method when DJ play is enabled in the playback apparatus of the present invention. First, the first motor 18 is rotationally driven to rotate the turntable 17 (S1501). Next, the rotation speed detection unit 20 detects the rotation speed of the turntable 17 (S1502). The signal reproduction unit 10 reads the audio signal from the recording medium 7 at a speed corresponding to the rotation speed of the turntable 17 and stores it in the buffer (S1503). The signal reproduction unit 10 interpolates and reads out the audio signal from the buffer so that the frequency does not change (S1504). The RIAA characteristic processing unit 13 calculates a frequency versus gain characteristic based on the rotation speed (S1505), and changes (processes) the audio signal with the calculated frequency versus gain characteristic (S1506).

  Next, the effect processing unit 14 determines whether or not the effect is valid and one of the effect types of type 2 to type 8 is selected (S1507). If the effect is invalid or the effect type of type 1 is selected (if the effect type of type 2 to type 8 is not selected), the effect processing unit 14 outputs the input audio signal through. The process proceeds to S1509. If the effect is valid and one of the effect types from type 2 to type 8 is selected, the process advances to step S1508. The effect processing unit 14 changes (processes) the audio signal with a coefficient corresponding to the selected effect type to generate the selected effect (S1508). An audio signal is output (S1509).

  As described above, when the rotational speed of the turntable is changed by applying the rotational force and the pressing force to the turntable 17 that the user self-runs, such as a disc jockey (DJ), the playback device of the present invention changes its rotational speed. Accordingly, frequency vs. gain characteristic changing processing based on the RIAA characteristic is performed on the audio signal read from the recording medium 7. As a result, it is possible to obtain an operation feeling and scratch sound as if the user is operating an analog record player, and satisfy a user who is familiar with the performance and scratch sound on the analog record. The configuration of the playback apparatus of the present invention is a configuration that is short in processing time and inexpensive.

  Furthermore, the playback apparatus of the present invention can select a plurality of effect types that reproduce the playback sound of the analog record cartridge, and has a function as if the cartridge of the analog record player was replaced. Further, since the effect processing can be invalidated and the effect type can be switched, it is possible to flexibly cope with the characteristics of the music and the user's preference.

  Furthermore, the playback apparatus of the present invention stores effect validity / invalidity and effect type information in the storage unit in association with an identification ID unique to the recording medium. When the reproducing apparatus next recognizes a recording medium having the same identification ID, the previous setting information is read. Thus, it is not necessary to set the effect type when the recording medium reproduced in the past is reproduced next time.

  In this embodiment, the case where data stored in a disk-shaped recording medium is reproduced has been described as an example. However, the configuration of the present invention is not limited to a disk-shaped recording medium such as a CD or a DVD. For example, the present invention can be applied to the case of reproducing audio information stored in an SD memory card or a hard disk. The playback device may have a recording function.

  The present invention can be used for a DJ (disc jockey) device that reproduces a digital audio signal recorded on a storage medium such as a CD or DVD and can be played with the same operation feeling as an analog record player. it can.

The block diagram which shows the outline of a structure of the reproducing | regenerating apparatus in embodiment of this invention Schematic plan view and front view of a turntable of a playback apparatus in an embodiment of the present invention The block diagram which shows the detail of a structure of the rotational speed detection part of the reproducing | regenerating apparatus in embodiment of this invention. The block diagram which shows the detail of a structure of the RIAA characteristic process part of the reproducing | regenerating apparatus in embodiment of this invention. The block diagram which shows the detail of a structure of the digital filter of the reproducing | regenerating apparatus in embodiment of this invention The block diagram which shows the detail of a structure of the output gain adjustment part of the reproducing | regenerating apparatus in embodiment of this invention The block diagram which shows the detail of a structure of the effect process part of the reproducing | regenerating apparatus in embodiment of this invention The figure which shows the example of the coefficient of the digital filter for every effect type in embodiment of this invention The table | surface which shows the example of the effect type and index value for every identification ID memorize | stored in the memory | storage part in embodiment of this invention Diagram showing frequency vs. gain characteristics change during recording and playback when playback speed is standard speed (A) Diagram showing frequency vs. gain characteristics change during recording and playback when playback speed is double (b) Frequency vs. gain characteristics change during recording and playback when playback speed is ½ times Illustration The figure which shows the frequency vs. gain characteristic when reproduction speed is 2 times The figure which shows the frequency versus gain characteristic when playback speed is 1/2 times The flowchart which shows the reproducing | regenerating method when DJ play of the reproducing | regenerating apparatus of Embodiment 1 of this invention is effective. The flowchart which shows the reproducing | regenerating method when DJ play of the reproducing | regenerating apparatus of Embodiment 2 of this invention is effective. The flowchart explaining the effect setting method of the reproducing | regenerating apparatus of embodiment of this invention The flowchart explaining the processing method of the audio | voice signal by the characteristic change part in embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Operation input display part 2 Reproduction | regeneration part 3 Turntable rotation detection part 4 Audio | voice output part 5 Operation input part 6 Display part 7 Recording medium 8 Second motor 9 Second motor drive part 10 Signal reproduction part 11 Control part 12 Characteristic change Unit 13 RIAA characteristic processing unit 14 effect processing unit 15 identification ID calculation unit 16 storage unit 17 turntable 18 first motor 19 first motor drive unit 20 rotational speed detection unit 21 tempo calculation unit 22 optical pickup 23 traverse motor drive unit 24 traverse motor 25 slip surface 30 optical sensor 31 pulse counter 41 first coefficient determination unit 42 first coefficient setting unit 43, 44, 45, 73, 74, 75 digital filter 46 output gain adjustment unit 71 second coefficient determination Unit 72 second coefficient setting unit 76 coefficient storage unit

Claims (10)

A motor,
A motor drive unit that controls and drives the motor to rotate at a predetermined rotational speed;
A turntable that is rotationally driven by the motor and capable of accelerating or decelerating or stopping or reversely rotating by applying a pressing force or rotational force from the outside;
A rotation speed detector that detects the rotation speed of the turntable and outputs rotation speed information;
A signal reproducing unit for reproducing the audio signal from a recording medium on which a digital audio signal is recorded at a reproduction speed corresponding to the rotation speed information;
A characteristic changing unit that changes a frequency-gain characteristic of the audio signal reproduced according to the rotation speed;
A playback apparatus comprising:   The reproduction apparatus according to claim 1, wherein the characteristic changing unit emphasizes or weakens a specific frequency band of the reproduced audio signal.   The playback apparatus according to claim 2, wherein the specific frequency band is calculated from the rotation speed. The signal reproduction unit reproduces the audio signal from the recording medium at a reproduction speed obtained by multiplying the recording speed by the ratio of the current rotation speed of the turntable to the rotation speed at no load, and records the audio signal. Change the frequency by the above ratio and output
The characteristic changing unit is
Storing at least one of a first frequency-to-gain characteristic and a second frequency-to-gain characteristic each of which is not flat and has a flat frequency-to-gain characteristic obtained by combining the two characteristics;
When the audio signal is equalized with the first frequency-to-gain characteristic at the time of recording, and further when the audio signal having the frequency changed by the above ratio at the time of recording is equalized with the second frequency-to-gain characteristic at the time of reproduction The frequency vs. gain characteristic of the reproduced audio signal is changed with the same characteristic as the frequency vs. gain characteristic obtained by synthesizing the recording and reproduction equalization received by the audio signal.
The reproducing apparatus according to claim 1. The signal reproduction unit reproduces the audio signal from the recording medium at a reproduction speed obtained by multiplying a recording speed by a ratio of a current rotation speed of the turntable to a rotation speed at no load, and the audio at the time of reproduction is reproduced. The audio signal is interpolated and read out and output so that the frequency of the signal does not change from that during recording,
The characteristic changing unit is
Storing at least one of a first frequency-to-gain characteristic and a second frequency-to-gain characteristic each of which is not flat and has a flat frequency-to-gain characteristic obtained by combining the two characteristics;
When the audio signal is equalized with the first frequency-to-gain characteristic at the time of recording, and further when the audio signal having the frequency changed by the above ratio at the time of recording is equalized with the second frequency-to-gain characteristic at the time of reproduction The frequency vs. gain characteristic of the reproduced audio signal is changed with the same characteristic as the frequency vs. gain characteristic obtained by synthesizing the recording and reproduction equalization received by the audio signal.
The reproducing apparatus according to claim 1.   The first frequency vs. gain characteristic is an equalizing characteristic of the RIAA (Recording Industry Association of America) standard, and the second frequency vs. gain characteristic is an inverse characteristic of the equalizing characteristic of the RIAA standard. The playback apparatus according to claim 4 or 5.   The characteristic changing unit stores one or a plurality of effect types having different frequency vs. gain characteristics, and changes the frequency vs. gain characteristics of the reproduced audio signal according to the effect type selected by the operator. The playback apparatus according to claim 1, wherein A storage unit for storing a table in which the storage medium identification information derived from the unique information of the storage medium and the effect type are associated;
The storage medium is replaceable,
The characteristic changing unit derives storage medium identification information from unique information of the storage medium that reproduces an audio signal, reads an effect type from the table based on the storage medium identification information, and is reproduced based on the effect type. The reproduction apparatus according to claim 7, wherein the audio signal is changed. The table is further associated with the recording medium identification information, the last time the effect type described in the table is read to change the audio signal reproduced from the storage medium, or from the last time to the present Storing an index value indicating the number of times of reading out the effect type described in the table in order to change the audio signal reproduced from the storage medium other than the storage medium,
When a recording area for writing new information in the storage unit is insufficient, the recording medium identification information with the oldest time or the recording medium identification information with the largest number of times is searched based on the index value. Write new information in the recording area of the recording medium identification information,
The playback apparatus according to claim 8. A step of rotationally driving a turntable capable of accelerating, decelerating, stopping, or reversely rotating by applying a pressing force or a rotational force from the outside at a predetermined rotational speed;
A rotational speed detecting step for detecting rotational speed of the turntable and outputting rotational speed information;
A signal reproduction step of reproducing the audio signal at a reproduction speed corresponding to the rotation speed information from a recording medium on which a digital audio signal is recorded;
A characteristic changing step of changing a frequency-gain characteristic of the audio signal reproduced according to the rotation speed;
A reproduction method characterized by comprising:

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