GB2165686A - A method of and apparatus for tape based sound reproduction - Google Patents

Abstract

A data track T1 and sound tracks T2 to T4 are recorded on a tape. The data track T1 recording comprises tone bursts which enable individual audio recordings to be identified and located. The existence of the data track T1 also inhibits the playing of tape in accordance with the invention on machines other than those according to the invention and vice versa. Specifically the data track occupies the position of a music track on conventional tapes. Further, music tracks may be recorded in the reverse direction to the conventional direction. A coin operated machine (Fig. 3) provides the selection of recordings from a plurality of tapes in cassettes, while the machine of (Figs. 2, 4) provides programmed continuous reproduction from such tapes. <IMAGE>

Description

SPECIFICATION A method of and apparatus for tape based sound reproduction The present invention relates to a method of and apparatus for tape based sound reproduction.

At the present time most public recorded music systems are record based. The main reason for this is security. Records are very difficult if not impossible for the unauthorised to reproduce. They are therefore favoured by the appropriate music licensing authorities.

Tape based systems, although having many practical advantages over records, suffer from the disadvantage that they can be relatively easily reproduced. Such systems are therefore open to unauthorised exploitation and for that reason have not met with favour with the appropriate licensing authorities. Conventional tape cassettes can be moved reproduced and used on similar unauthorised music reproducing systems.

According to one aspect of the present invention, there is provided a method of tape based sound reproduction including the step of recording a data track and a sound track on tape, the data track inhibits the playing of tapes prepared on special adapted machines and conventional machines as well as providing a means of locating individual recordings on the sound track.

According to another aspect of the present invention, there is provided a machine for reproducing sound from a tape comprising a head for reading a data track and a sound track on the tape, and a means for determining from the data read the position of an individual recording on the sound track and also of inhibiting playing of the tape unless the data track is present.

According to a further aspect of the present invention, there is provided a recording tape comprising a data track and an audio track in which the data track enables playing of recording on the special machines as well as individual recordings on the music track to be located.

In a preferred embodiment of the invention, there are four recording tracks, one or two of which are data tracks and the remainder sound tracks depending usually on whether the system is for mono or stereo sound reproduction. The existence of the data track imposes incompatibility between the equipment of the invention and conventional equipment. This is important particularly where the equipment is installed in a public place as is often the case. The data track enables music to be continuously played in accordance with a preselected program from a plurality of tape cassettes. It also permits selections to be made from a plurality of cassettes to provide a viable alternative to the disc based juke box.

The beginning and end of individual recordings on the sound tracks may be identified by tone bursts on the data track. These tone bursts may be coded so that specific recordings may be uniquely identified. Recording position may also be identified by counting tone bursts from a specific "start of tape" tone burst. Coding of tone bursts also enables specific tapes to be matched to specific machines by providing an internal register in the machine in which the specific tone burst is stored.

In order that the invention may be more clearly understood, embodiments thereof will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 diagrammatically shows tape format for mono reproduction, Figure 2 diagrammatically shows tape format for stereo reproduction, Figure 3 shows a block circuit diagram for a coin operated mono reproduction machine, Figure 4 shows a block circuit diagram for a stereo reproduction machine operated in accordance with a predetermined program, and Figure 5 shows a diagrammatic external view of a unit incorporating the machine of Figure 3 or Figure 4.

Referring to Figure 1, the magnetic tape 1 comprises four magnetic recording tracks T1 to T4. Tracks T1, T3 and T4 are music tracks. Track T2 is a data track. The data track T2 enables particular recordings on each of the music tracks to be located. To this end the data track comprises a plurality of tone bursts which respectively indicate the starts, and a plurality of tone bursts which respectively indicate the ends, of the individual music recordings on the music tracks. To select a particular recording for playing, the particular music track on which that recording occurs is selected by a control computer 37 (shown on Figure 3) and the position of the recording on that track is located by counting the appropriate number of start tone bursts. When the recording has been played the end tone burst enables the end of the recording to be determined.This format is incompatible with conventional tape playing machines and prevents a tape according to the present invention being played satisfactorily on a conventional machine and a tape for a conventional machine being played. satisfactorily on a machine according to the present invention. The latter machine only reproduces music for tapeplay in one forward direction. If a tape according to the invention is played on a conventional machine the data track T1, which is recorded at a higher level than the adjacent music track T2, will drown that music track in the normal forward direction of music play. In the normal, reverse, direction the other two music tracks T3 and T4 will be reproduced in the reverse direction. If a conventional tape were played on a machine according to the invention the third and fourth music tracks would be reproduced in the reverse direction.In addition the non-existence of the data track will inhibit the play.

The machine of Figure 3 has provision for playing recordings from any one of eight cassettes. Each cassette 30 is provided with a mechanical control 31, including a tape transport mechanism, and a magnetic reading head 32. All eight controls 30 are under the control of the computer 37 which is connected also to a music selection matrix 33, coin acceptor 34, selection memory 35, and sixteen segment alpha/numeric display 36.

Output signals from the heads are fed to a signal processing circuitry which comprises a V.E. mixer 38 D.B.X. decoder 39, expander 40 tone control 41 and line amplifier 42. Connected to this signal processing circuitry is microphone input circuitry comprising a pre-amplifier 43 tone control 44 and override 45.

The eight tape transport mechisms and corresponding cassettes 30 are arranged in a single unit 50 as shown in Figure 5. An L.E.D.

display 51 comprises three lines 52, 53 and 54 of eight L.E.D.'s each. Line 52 indicates which tapes are ready to play, line 53 which tape is playing and line 54 which tape is rewinding. Tapes are removable but require a special tool to release a lock 55 on each transport mechanism door. Display 36 and coin acceptor 34 are not shown.

The control computer acts to rewind tapes after playing to an optimum position usually with substantially equal amounts of tape on the reels of the cassette. The most popular music recordings would be adjacent this central position and the least popular furthest away. Recordings which are very popular could appear on more than one cassette so as to avoid any delay with repeated sequential selections of the same recording. Fading in and out of sequentially played recordings could also be achieved. Automatic muting would also be provided for during microphone announcements.

Figures 2 and 4 illustrate a system similar to the system of Figures 1 and 3, but for a programmed continuous stereo reproduction music system. There are again four tracks 2T1 to 2T4 on the tape, but this time tracks 2T1 and 2T2 are for data and tracks 2T3 and 2T4 are for music. On the normal machine, in the forward direction of play, the data tracks 2T1 and 2T2 would be read and in the re verse direction the music tracks 2T3 and 2T4.

Since these tracks are recorded for forward play, the music would be reproduced in re verse (the machine, as with the mono ma chine, only reproduces music for tape play in one direction). One of the data tracks 2T1 carries a 6kc/s continuous carrier tone on which coded tone bursts of 10KHz are super imposed to indicate the beginning and/or end of individual recordings. When the tape is being played, circuitry 74 associated with the appropriate head recognises the carrier signal.

If, after a predetermined delay of, for example, five seconds, the carrier tone is not present, the machine will shut down. The tone burst is compared with an internal register which identifies the correct code. if the code is not correct the machine will again shut down. Attempting to play an incompatible tape on the machine would therefore simply result in the machine shutting down. Coding permits specific tapes to be compatible only with specific machines according to the invention, not simply specific as between inventive and conventional machines.

Referring particularly to Figure 4, the machine is similar to that of Figure 3 (equivalent parts bear the same references as those of Figure 3), but the circuitry includes means for playing recordings from the eight tapes in accordance with a predetermined program rather than in response to a coin validated selection.

Thus, the circuitry comprises a program counter and mechanical control 60 connected through a timer 61 and gate 62 to a comparitor 63, memory 64 and clock and counter 65.

The comparitor 63 is also connected via latch 66, p.p.m. decoder and UART 67, 10kc/s band pass filter and V.E. amplifier 68 to the output from the head 32 of the eighth cassette. The other input to the gate is connected via a detector 73 and a 6 kc/s band pass filter 74 and to the output of V.E. amplifier 69. Items 38 to 42 comprises two chan nels to provide for stereo and a coin operated inhibit circuitry 75 is provided to mute the music from the machine when a selection is made on a juke box in the same establishment.

The physical arrangement of the eight tapes and the L.E.D. display is the same as that shown in Figure 5. A coin acceptor mecha nism and indicator as to which selection was playing would not be necessary.

It will be appreciated that the above em bodiments have been described by way of example only and that many variations are possible without departing from the scope of the invention. For example, the continuous programmed music system could be mono and the juke box system could be stereo.

More or fewer cassettes could be provided for. Advertisements could be provided as an inherent part of the programme in the pro grammed system and to be played when no customer selection is currently playing in the case of the juke box.

Claims (19)

1. A method of tape based sound reproduc tion including the step of recording a data track and a sound track on tape, the data track inhibiting the playing of tapes prepared on specially adapted machines and conven tional machines and providing a means of locating individual recordings on the sound track.

2. A method as claimed in claim 1, in which there are four recording tracks, one or two of which are data tracks and the remainder sound tracks.

3. A method as claimed in claim 1 or 2, in which the data track enables music to be continuously played in accordance with a preselected program from a plurality of tape cassettes.

4. A method as claimed in claim 1, 2 or 3 in which individual recordings on the sound tracks are identified by the tone bursts on the data track.

5. A method as claimed in claim 4, in which the tone bursts are coded so that specific recordings may be identified.

6. A method as claimed in claim 4 or 5, in which recording position is identified by counting tone bursts from a start of tape tone burst.

7. A method as claimed in claim 1, in which the tone bursts are matched to a specific machine.

8. A method of tape based sound reproduction substantially as hereinbefore described with reference to Figure 1,2,3,4 or 5 of the accompanying drawings.

9. A machine for reproducing sound from a tape comprising a head for reading a data and a sound track on the tape and means for determining from the data read the position of an individual recording on the sound track and also of inhibiting playing of the tape unless the data track is present.

10. A machine as claimed in claim 9, in which means are provided for recognising a start pulse at or near the beginning of the tape.

11. A machine as claimed in claim 9 or 10, in which means are provided for counting pulses between adjacent recordings on the sound track to identify a particular recording.

12. A machine as claimed in claim 9, 10 or 11, in which means are provided for decoding coded tonebursts in order to identify specific recordings.

13. A machine as claimed in any of claims 9 to 12, in which means are provided for playing two or more cassettes and means are provided for switching from cassette to cassette in accordance with a predetermined program.

14. A machine for reproducing sound from a tape substantially as hereinbefore described with reference to Figure 1,2,3,4 or 5 of the accompanying drawings.

15. A recording tape comprising a data track and an audio track in which the data track enables playing of recording on the special machines as well as individual recordings on the music track to be located.

16. A recording tape as claimed in claim 15, in which a start pulse is recorded at or near the beginning of the tape.

17. A recording tape as claimed in claim 16, in which tone bursts are disposed between individual recordings on the tape.

18. A recording tape as claimed in claim 17, in which the tone bursts are coded to identify specific recordings.

19. A recording tape substantially as hereinbefore described with reference to Figure 1,2,3,4 or 5 of the accompanying drawings.