Music laboratory

Claim 7

The combination according to claim 3, wherein said teacher station includes an electrical musical instrument providing a teacher musical signal source, teacher headphone at said teacher station, switching means at said teacher station for at will connecting said outgoing student signal line to said teacher headphone and said teacher musical signal source to said incoming student signal line.

Claim 10

The combination according to claim 5, wherein is provided an isolative resistive mixer network, means connected to corresponding ones of said stationary contacts for at will connecting all the incoming lines of a group of said student stations to said isolative resistive mixer network.

Claim 11

The combination according to claim 6, wherein is provided means connected to corresponding ones of said stationary switch contacts for at will connecting any selected individual incoming line to said teacher station to the exclusion of all other incoming lines.

Claim 14

In a music teaching laboratory having a plurality of electrical musical instruments providing audio tone signals, an incoming line for each of said instruments, an outgoing line for each of said instruments, a relatively high resistance network connecting each incoming line to each outgoing line and providing isolation therebetween for said audio tone signals, headphones permanently connected betwEen an intermediate point of said resistance network and ground, an amplifier having an input and an output circuit, a loudspeaker, and means for connecting said output circuit selectively directly to said outgoing line or directly to said loudspeaker, said headphones having each relatively low resistance of the order of less than 5 percent of the ohmage of one of said relatively high resistance networks, whereby said headphones provide shunt impedances which enhance the isolation provided by said relatively high resistance networks.

Claim 15

In a music teaching laboratory having a plurality of electrical musical instruments providing audio tone signals, an incoming line for each of said instruments, an outgoing line for each of said instruments, a relatively high resistance network connecting each incoming line to each outgoing line and providing isolation therebetween for said audio tone signals, headphones permanently connected betwEen an intermediate point of said resistance network and ground, an amplifier having an input and an output circuit, a loudspeaker, and means for connecting said output circuit selectively directly to said outgoing line or directly to said loudspeaker, said headphones having each relatively low resistance of the order of less than 5 percent of the ohmage of one of said relatively high resistance networks, whereby said headphones provide shunt impedances which enhance the isolation provided by said relatively high resistance networks.

Claim 16

In a music laboratory, an incoming teacher line, a teacher station including a teacher musical instrument providing a source of electrical output signals, an output teacher line connected to said source, relatively high isolating resistance connected between said incoming and output lines, a relatively low input impedance tape recorder for receiving signals from said incoming line, and a connection from said tape recorder to an intermediate point of said relatively high resistances.

Claim 17

In a music laboratory, an incoming teacher line, a teacher station including a teacher musical instrument providing a source of electrical output signals, an output teacher line connected to said source, relatively high isolating resistance connected between said incoming and output lines, a relatively low input impedance tape recorder for receiving signals from said incoming line, and a connection from said tape recorder to an intermediate point of said relatively high resistances.

Claim 18

The combination according to claim 10, wherein is additionally provided further relatively high isolating resistance connected between said lines in parallel with said first relatively high resistance, and a second reproducing means connected between a midpoint of said further relatively high resistance and ground, said second reproducing means having relatively low resistance to further decouple said lines while providing a preselected signal level to said second reproducing means.

Claim 19

The combination according to claim 10, wherein is provided a plurality of pupil stations each including a signal source and a signal receiver connected respectively to an outgoing student line and an incoming student line, and means for selectively and at will connecting said incoming student lines to said outgoing teacher line and said outgoing student lines to said incoming teacher line.

Claim 20

The combination according to claim 12, wherein said means for selectively and at will connecting is located at said teacher station.

Claim 21

In a music laboratory, an incoming signal line for first signals, an outgoing signal line for second signals, a relatively high resistance network joining said lines and providing isolation therebetween for both said signals, a relatively low resistance headset connected between an approximate midpoint of said resistance network and ground, said relatively low resistance being selected to provide decoupling between said lines when taken in conjunction with said relatively high resistance network, a dummy load connected between said outgoing signal line and ground, said dummy load having an impedance of the order of magnitude of said relatively low resistance, a power amplifier having an input terminal and an output terminal, a loudspeaker, a microphone, a musical instrument pickup, means selectively and at will connecting said microphone or said musical instrument pickup to said input terminal, and means selectively and at will connecting said dummy load or said loudspeaker to said output terminal.

Claim 22

In a music laboratory, an incoming signal line for first signals, an outgoing signal line for second signals, a relatively high resistance network joining said lines and providing isolation therebetween for both said signals, a relatively low resistance headset connected between an approximate midpoint of said resistance network and ground, said relatively low resistance being selected to provide decoupling between said lines when taken in conjunction with said relatively high resistance network, a dummy load connected between said outgoing signal line and ground, said dummy load having an impedance of the order of magnitude of said relatively low resistance, a power amplifier having an input terminal and an output terminal, a loudspeaker, a microphone, a musical instrument pickup, means selectively and at will connecting said microphone or said musical instrument pickup to said input terminal, and means selectively and at will connecting said dummy load or said loudspeaker to said output terminal.

Claim 23

The combination according to claim 14, wherein is provided a plurality of groups of student stations, a plurality of group lines, means connecting each of said group lines to each of said student stations of a group of student stations and means for at will selectively coupling said output of said power amplifier to all said group lines, or to a selected group of group lines or to a selected group line.

Claim 24

The combination according to claim 15, wherein said pupil stations have output lines and said teacher station has headphones, said means for at will connecting output lines of selected student stations to said headphones of said teacher station.

Claim 25

In a music laboratory, a plurality of n student stations, where n is an integer, each of said stations including an electrical musical instrument, an outgoing linE connected to convey electrical signals from said electrical musical instrument, earphones, an incoming line connected to convey electrical signals to said earphones, means for conveying electrical tone signals from an electrical musical instrument at each station to the earphones at said each station at a first level, and means for additionally conveying electrical signals from all of said outgoing lines to the incoming line at each station, whereby each student can hear his own playing distinguishably from the playing of the remaining students.

Claim 26

In a music laboratory, a plurality of n student stations, where n is an integer, each of said stations including an electrical musical instrument, an outgoing linE connected to convey electrical signals from said electrical musical instrument, earphones, an incoming line connected to convey electrical signals to said earphones, means for conveying electrical tone signals from an electrical musical instrument at each station to the earphones at said each station at a first level, and means for additionally conveying electrical signals from all of said outgoing lines to the incoming line at each station, whereby each student can hear his own playing distinguishably from the playing of the remaining students.

Claim 27

In a music class training system, a microphone, a source of music signals deriving from an electrical musical instrument, an amplifier having an input circuit and an output circuit, first switch means for selectively connecting said microphone and said source of music signals to said input circuit, second switch means connected to said output circuit, an outgoing signal line, a loudspeaker, means connecting said second switch means selectively to said outgoing signal line and said loudspeaker, an incoming signal line, a pair of relatively high isolating resistances connected between said outgoing and incoming signal lines, and a headset connected between the junction of said resistances and a point of reference potential, said headset being of relatively low resistance.

Claim 28

In a music class training system, a microphone, a source of music signals deriving from an electrical musical instrument, an amplifier having an input circuit and an output circuit, first switch means for selectively connecting said microphone and said source of music signals to said input circuit, second switch means connected to said output circuit, an outgoing signal line, a loudspeaker, means connecting said second switch means selectively to said outgoing signal line and said loudspeaker, an incoming signal line, a pair of relatively high isolating resistances connected between said outgoing and incoming signal lines, and a headset connected between the junction of said resistances and a point of reference potential, said headset being of relatively low resistance.

Claim 29

In a music laboratory, a plurality of student stations each including an electrical musical instrument, a separate outgoing line connected to convey signals from each of said instruments, a headphone at each of said student stations, a separate incoming line at each of said student stations connected to convey signal to said headphone at that station, a passive impedance network means for concurrently conveying signals from an incoming line at each station and from the outgoing line at that station to said headphones while isolating said lines from each other, and means for at will connecting all said outgoing lines concurrently to all said headphones via said incoming lines.

Claim 30

In a music laboratory, a plurality of student stations each including an electrical musical instrument, a separate outgoing line connected to convey signals from each of said instruments, a headphone at each of said student stations, a separate incoming line at each of said student stations connected to convey signal to said headphone at that station, a passive impedance network means for concurrently conveying signals from an incoming line at each station and from the outgoing line at that station to said headphones while isolating said lines from each other, and means for at will connecting all said outgoing lines concurrently to all said headphones via said incoming lines.

Claim 31

The combination according to claim 19 wherein is provided a teacher''s station, said last means being located at said teacher''s station.

Claim 32

The combination according to claim 20, wherein said teacher station includes a source of music signals, and means connecting said source of music signals selectively at will to any one of said incoming lines or to all said incoming lines. 22. The combination according to claim 20, wherein said teacher station includes a headphone and means at said teacher station for selectively connecting said headphone to any selected one of said outgoing lines and to all said outgoing lines; whereby said teacher may monitor any one of said students or the ensemble of all said students.

Claim 33

The combination according to claim 21, wherein said plurality of student stations includes plural groups of stations, and wherein said teacher station includes means connecting said source of music signals to any group of said stations to the exclusion of the other groups.

Claim 34

The combination according to claim 22, wherein said plurality of student stations includes plural groups of stations and wherein said teacher station includes means for connecting said source of music signals and said headphone located at said teacher station selectively to any one of said groups of stations.

Claim 35

In a music teaching laboratory, an audio power amplifier having an input and an output, said output having a low source impedance and providing plural watts of power, a loudspeaker, a source of music signals deriving from a musical instrument, switch means connecting said loudspeaker at will to said output, headphones having impedance of the order of 4 ohms, a resistive network connectable by said switch means from said output to said headphones, said resistive network having impedance of about 220 ohms, an ouTgoing audio line, a resistance of the order of the resistance of said loudspeaker connected between said outgoing line and ground, an incoming line, a second resistive network of about 220 ohms connected between said incoming line and said headphones.

Claim 36

In a music teaching laboratory, an audio power amplifier having an input and an output, said output having a low source impedance and providing plural watts of power, a loudspeaker, a source of music signals deriving from a musical instrument, switch means connecting said loudspeaker at will to said output, headphones having impedance of the order of 4 ohms, a resistive network connectable by said switch means from said output to said headphones, said resistive network having impedance of about 220 ohms, an ouTgoing audio line, a resistance of the order of the resistance of said loudspeaker connected between said outgoing line and ground, an incoming line, a second resistive network of about 220 ohms connected between said incoming line and said headphones.

Claim 37

In a music teaching laboratory, a plurality of student stations arranged in a group, each of said stations including a source of electrical tone signals deriving from a musical instrument, a separate outgoing line to convey signals from each of said sources, a headphone a separate incoming line to convey signals to each of said stations, a passive network for conveying signals from an incoming line at each station and from the outgoing line at that station to said headphones while isolating said lines from one another; and means for at will connecting all said outgoing lines from said stations of said group to all incoming lines in said group.

Claim 38

In a music teaching laboratory, a plurality of student stations arranged in a group, each of said stations including a source of electrical tone signals deriving from a musical instrument, a separate outgoing line to convey signals from each of said sources, a headphone a separate incoming line to convey signals to each of said stations, a passive network for conveying signals from an incoming line at each station and from the outgoing line at that station to said headphones while isolating said lines from one another; and means for at will connecting all said outgoing lines from said stations of said group to all incoming lines in said group.

Claim 41

The combination according to claim 27, wherein the source of further electrical signals includes an electrical musical instrument, the combination further comprising a microphone, and switch means for at will coupling said microphone to said means for reproducing at all said student stations.

Claim 44

In a music teaching laboratory, an audio power amplifier having an input circuit and an output circuit, said output circuit having a low source impedance and providing plural watts of power, an electrical musicaL instrument having a source of music signals connected to said input circuit, a loudspeaker, switch means connecting said loudspeaker at will to said output circuit, headphones having a predetermined low impedance, a relatively high impedance resistive network connectable by said switch means from said output circuit to said headphones, said high impedance network including resistance of at least 40 times that of said headphones, an outgoing audio line connected through said resistive network to said headphones, a relatively low impedance connected between said outgoing line and ground, an incoming line, a second relatively high resistive network connected between said incoming line and said headphone and having an impedance of the order of magnitude of said first resistive network.

Claim 45

In a music teaching laboratory, an audio power amplifier having an input circuit and an output circuit, said output circuit having a low source impedance and providing plural watts of power, an electrical musicaL instrument having a source of music signals connected to said input circuit, a loudspeaker, switch means connecting said loudspeaker at will to said output circuit, headphones having a predetermined low impedance, a relatively high impedance resistive network connectable by said switch means from said output circuit to said headphones, said high impedance network including resistance of at least 40 times that of said headphones, an outgoing audio line connected through said resistive network to said headphones, a relatively low impedance connected between said outgoing line and ground, an incoming line, a second relatively high resistive network connected between said incoming line and said headphone and having an impedance of the order of magnitude of said first resistive network.

Claim 46

In a music laboratory, a group of student stations, each of said student stations including an electrical musical instrument providing electrical tone signals representative of music played on said instrument, an output line, means for applying said electrical signals to said output line, an input line, a sound transducer connected to receive signals from both said output and input lines; a group amplifier having an input and an output, switch means (44) for selectively applying concurrently all said signals from all said output lines to said input of said group amplifier and (R7) from said output of said group amplifier to all said input lines, whereby each student hears his own playing from both said input and output lines and the playing of other students only from an input line.

Claim 47

In a music laboratory, a group of student stations, each of said student stations including an electrical musical instrument providing electrical tone signals representative of music played on said instrument, an output line, means for applying said electrical signals to said output line, an input line, a sound transducer connected to receive signals from both said output and input lines; a group amplifier having an input and an output, switch means (44) for selectively applying concurrently all said signals from all said output lines to said input of said group amplifier and (R7) from said output of said group amplifier to all said input lines, whereby each student hears his own playing from both said input and output lines and the playing of other students only from an input line.

Claim 48

The combination according to claim 31 further comprising a teacher station, a source at said teacher station of further electrical signals representative of music, further switch means (67- 1 to 6) at said teacher station for directing said further signals selectively to said input line of any one of said student stations or concurrently (62 A or B or C or D) to said input lines of all said student stations, said further switch means being arranged to apply said further signals from said teacher station to said input of said group amplifier whereby to concurrently apply said electrical signals to said input lines of all said student stations.

Claim 49

In a teaching system for teaching music to a class composed of plural groups of music students, each group including plural students, a teacher''s station having interlocked group selection pushbuttons, one for each group, interlocked individual pupil pushbuttons one for each student of a group, a class selection pushbutton, and a separate mode selection device for each of said groups, a pupil source of information bearing signal available to each of said pupils, a pupil headset and a microphone available to each of said students, a teacher microphone, a teacher headset, a teacher source of information bearing signals, means responsive to actuation of said class button for interconnecting all said pupil headsets with said teacher microphone and said teacher source, means responsive to actuation of any one of said group buttons for interconnecting only the headsets of the pupils of a corresponding group with said teacher microphone and said teacher source, means responsive to actuation of any of said individual pupil pushbuttons for connecting only one individual pupil of a group selected in response to actuation of a group selection button with said teacher microphone and said teacher source, and means responsive to actuation of said mode selection switch for determining selectively that the pupil sources and headsets of a group selected by any one of said group selection buttons shall be interconnected with each other in ensemble.

Claim 50

In a teaching system for teaching music to a class composed of plural groups of music students, each group including plural students, a teacher''s station having interlocked group selection pushbuttons, one for each group, interlocked individual pupil pushbuttons one for each student of a group, a class selection pushbutton, and a separate mode selection device for each of said groups, a pupil source of information bearing signal available to each of said pupils, a pupil headset and a microphone available to each of said students, a teacher microphone, a teacher headset, a teacher source of information bearing signals, means responsive to actuation of said class button for interconnecting all said pupil headsets with said teacher microphone and said teacher source, means responsive to actuation of any one of said group buttons for interconnecting only the headsets of the pupils of a corresponding group with said teacher microphone and said teacher source, means responsive to actuation of any of said individual pupil pushbuttons for connecting only one individual pupil of a group selected in response to actuation of a group selection button with said teacher microphone and said teacher source, and means responsive to actuation of said mode selection switch for determining selectively that the pupil sources and headsets of a group selected by any one of said group selection buttons shall be interconnected with each other in ensemble.

Claim 51

In a music laboratory system, a teacher station having an incoming and an outgoing teacher line, a teacher musical instrument prOviding tone signals to said outgoing line, a headphone coupled simultaneously to both said teacher lines, a microphone, means coupling said microphone only to said outgoing line, and means decoupling said microphone from said incoming line, said last means including said headphone.

Claim 52

In a music laboratory system, a teacher station having an incoming and an outgoing teacher line, a teacher musical instrument prOviding tone signals to said outgoing line, a headphone coupled simultaneously to both said teacher lines, a microphone, means coupling said microphone only to said outgoing line, and means decoupling said microphone from said incoming line, said last means including said headphone.

Claim 53

The claim according to claim 34, wherein is further provided a plurality of pupil stations each including an electronic musical instrument, each of said pupil stations including a pupil incoming line and an outgoing line connected to said instrument, a headphone coupled simultaneously to both the outgoing and incoming pupil lines, a microphone, means coupling said microphone only to said outgoing line and means decoupling said microphone from said incoming line, said last means including said headphone.

Claim 54

The combination according to claim 35, wherein is included means for at will concurrently connecting said teacher outgoing line with any one only of said pupil incoming lines and said teacher incoming line only with the outgoing line of said any one only of said pupil incoming lines.

Claim 55

The combination according to claim 36, wherein is included means for at will connecting said teacher outgoing line with a preselected group only of said pupil incoming lines and said teacher incoming line with said preselected group only of said pupil outgoing lines, said last means including plural switches operated by a single pushbutton.

Claim 56

The combination according to claim 37, wherein is further included means for additionally intercoupling all said pupil incoming lines with all said pupil outgoing lines of said group, said last means including plural switches selected by a single switch actuator additional to said single pushbutton.

Claim 57

The combination according to claim 38, wherein said last means includes only one amplifier having its input connected commonly to all said outgoing lines, and its output connected commonly to all said incoming lines.

Claim 58

In a music laboratory, a teacher station including a teacher electrical musical instrument and plural student stations, each including a student electrical musical instrument, each of said stations including an incoming signal line and an outgoing signal line connected to the instrument at that station, a separate first pushbutton operatively associated with each said secondary stations and located at said teacher station, a further pushbutton located at said teacher station and operatively associated with all said student stations, a rotatable knob, said first pushbuttons being interlocked to enable actuation of only one at a time, means responsive to actuation of any selected one of said first pushbuttons for interconnecting the incoming line of said teacher station with a corresponding outgoing line of a selected one of said pupil stations, and the incoming line of the selected one of said pupil stations to the outgoing line of said teacher station, means responsive to operation of said further pushbutton for connecting the incoming line of said teacher station to all said outgoing lines and the outgoing line of said teacher station to all said incoming lines, and means operative only in a selected position of said rotatable knob for interconnecting each of said incoming lines to all said outgoing lines.

Claim 59

In a music laboratory, a teacher station including a teacher electrical musical instrument and plural student stations, each including a student electrical musical instrument, each of said stations including an incoming signal line and an outgoing signal line connected to the instrument at that station, a separate first pushbutton operatively associated with each said secondary stations and located at said teacher station, a further pushbutton located at said teacher station and operatively associated with all said student stations, a rotatable knob, said first pushbuttons being interlocked to enable actuation of only one at a time, means responsive to actuation of any selected one of said first pushbuttons for interconnecting the incoming line of said teacher station with a corresponding outgoing line of a selected one of said pupil stations, and the incoming line of the selected one of said pupil stations to the outgoing line of said teacher station, means responsive to operation of said further pushbutton for connecting the incoming line of said teacher station to all said outgoing lines and the outgoing line of said teacher station to all said incoming lines, and means operative only in a selected position of said rotatable knob for interconnecting each of said incoming lines to all said outgoing lines.

Claim 60

The combination according to claim 40, wherein said last means includes a common amplifier for coupling all said incoming lines to all said outgoing lines.