Auditorium simulator and the like employing different pinna filters for headphone listening

Claim 2

For use with an auditorium simulator for sound performances having an input for the signal to be played and outputs for right and left transducers that are closely associated with the respective ears of the listener, listener simulating means comprising pinna response simulating circuitry having characteristics simulating differences between the left and right pinnas of a listener for modifying said signal and applying to said right and left transducers outputs in the form of different direction signifying transforms in accordance with the effect of the listener being disposed in the auditorium being simulated, the output of said pinna response simulating circuitry corresponding as a function of amplitude and frequency to the binaural pinna disparity auditory localization cue of the listener.

Claim 3

An auditorium simulator for producing separate signals for two signal-to-sound transducers to be used respectively with the right and left ears of a listener, comprising a source for a signal stream, right and left summing circuits each connected to the signal stream and to a plurality of additional inputs, and input to each summing circuit comprising a connection to the signal stream through reflection conditioning circuitry which introduces delay and attenuation representing the path effects of single reflection of the sound from a given left or right side wall of the auditorium to be simulated, a first of said summing circuits corresponding to the given side wall receiving its input through respective conditioning circuitry simulating for the input a given direct path from the sound source to the given wall, thence to the ear, and through first pinna response simulating circuitry that simulates pinna response of one ear of the listener as a function of frequency at the angle of incidence of said given path upon the listener, and the other summing circuit receiving its input through conditioning circuitry simulating a path like that of said first summing circuitry and including an additional attenuation and delay based upon the effect of the listener's head being interposed in the path of the reflected sound from the direction being simulated, and through second pinna response simulating circuitry that simulates pinna response of the other ear of the listener as a function of frequency at the angle of incidence of said given path upon the listener, said first and second pinna response simulating circuitries having different filter characteristics simulating differences between the right and left pinnas of a listener, the respective conditioning circuits and pinna response simulating circuitries altering the signals before reaching the respective transducers to impart realistic simulation of sound reception in an auditorium.

Claim 4

An auditorium simulator for producing separate signals for two signal-to-sound transducers to be used respectively with the right and left ears of a listener, comprising a source for a signal stream, right and left summing circuits each connected to the signal stream and to a plurality of additional inputs, and input to each summing circuit comprising a connection to the signal stream through reflection conditioning circuitry which introduces delay and attenuation representing the path effects of single reflection of the sound from a given left or right side wall of the auditorium to be simulated, a first of said summing circuits corresponding to the given side wall receiving its input through respective conditioning circuitry simulating for the input a given direct path from the sound source to the given wall, thence to the ear, and through first pinna response simulating circuitry that simulates pinna response of one ear of the listener as a function of frequency at the angle of incidence of said given path upon the listener, and the other summing circuit receiving its input through conditioning circuitry simulating a path like that of said first summing circuitry and including an additional attenuation and delay based upon the effect of the listener's head being interposed in the path of the reflected sound from the direction being simulated, and through second pinna response simulating circuitry that simulates pinna response of the other ear of the listener as a function of frequency at the angle of incidence of said given path upon the listener, said first and second pinna response simulating circuitries having different filter characteristics simulating differences between the right and left pinnas of a listener, the respective conditioning circuits and pinna response simulating circuitries altering the signals before reaching the respective transducers to impart realistic simulation of sound reception in an auditorium.

Claim 5

An auditorium simulator for producing separate signals for two signal-to-sound transducers to be used respectively with the right and left ears of a listener, comprising a source for right and left signal streams representing right and left sound streams produced by spaced apart pick-ups from a sound source, right and left summing circuits each connected to the respective signal stream and to a plurality of additional inputs, a pair of inputs to each summing circuit comprising connections respectively to the right and left signal streams through reflection conditioning circuitry which introduces delay and attenuation representing the path effects of single reflection of the sound from a given left or right side wall of the auditorium to be simulated, a first of said summing circuits corresponding to the given side wall receiving its pair of inputs through respective conditioning circuitry simulating for each input a path from the sound source to the given wall, then to the ear, the delays in the pair of inputs being different in an amount representing a difference in length of the sound paths, and the other summing circuit receiving its inputs through conditioning circuitry simulating paths like that of said first summing circuitry and including an additional attenuation and delay based upon the effect of the listener's head being interposed in the path of the reflected sound from the direction being simulated, the respective conditioning circuits altering the signals before reaching the respective listener's ears to impart realistic simulation of sound reflection from a given direction in an auditorium and a pinna simulator filter connected to each said summing circuit, each said pinna simulator filter being operable to attenuate the signals as a function of frequency over the range of 6-12 kilohertz in accordance with the different pinna responses of the left and right ears of the listener at the simulated angles of incidence of the simulated sound paths upon the listener.

Claim 6

An auditorium simulator for producing separate signals for two signal-to-sound transducers to be used respectively with the right and left ears of a listener, comprising a source for right and left signal streams representing right and left sound streams produced by spaced apart pick-ups from a sound source, right and left summing circuits each connected to the respective signal stream and to a plurality of additional inputs, a pair of inputs to each summing circuit comprising connections respectively to the right and left signal streams through reflection conditioning circuitry which introduces delay and attenuation representing the path effects of single reflection of the sound from a given left or right side wall of the auditorium to be simulated, a first of said summing circuits corresponding to the given side wall receiving its pair of inputs through respective conditioning circuitry simulating for each input a path from the sound source to the given wall, then to the ear, the delays in the pair of inputs being different in an amount representing a difference in length of the sound paths, and the other summing circuit receiving its inputs through conditioning circuitry simulating paths like that of said first summing circuitry and including an additional attenuation and delay based upon the effect of the listener's head being interposed in the path of the reflected sound from the direction being simulated, the respective conditioning circuits altering the signals before reaching the respective listener's ears to impart realistic simulation of sound reflection from a given direction in an auditorium and a pinna simulator filter connected to each said summing circuit, each said pinna simulator filter being operable to attenuate the signals as a function of frequency over the range of 6-12 kilohertz in accordance with the different pinna responses of the left and right ears of the listener at the simulated angles of incidence of the simulated sound paths upon the listener.

Claim 7

The auditorium simulator of claim 3 in which said signal source comprises a two-channel stereo player for playing a recording of respective right and left signal streams.

Claim 8

An auditorium simulator for sound performances having an input for the signal to be played and outputs for right and left transducers that are closely associated with the respective ears of the listener, the simulator having a delay means for providing delayed versions of the signal for simulating the lengths of predetermined sound paths in an auditorium, the delays of said versions being between about 10 to 100 milliseconds, and listener simulating means comprising pinna effect filter means that establishes different filter characteristics for the respective transducers simulating differences between the right and left pinnas of a listener, the output of said pinna effect filter means corresponding as a function of the amplitude and frequency to the binaural pinna disparity auditory localization cue of the listener producing from said versions outputs for the left and right transducers in the form of different direction-signifying transforms in accordance with the effect of the listener being disposed in the respective sound paths being simulated.

Claim 9

An auditorium simulator for sound performances having an input for the signal to be played and outputs for right and left transducers that are closely associated with the respective ears of the listener, the simulator having a delay means for providing delayed versions of the signal for simulating the lengths of predetermined sound paths in an auditorium, the delays of said versions being between about 10 to 100 milliseconds, and listener simulating means comprising pinna effect filter means that establishes different filter characteristics for the respective transducers simulating differences between the right and left pinnas of a listener, the output of said pinna effect filter means corresponding as a function of the amplitude and frequency to the binaural pinna disparity auditory localization cue of the listener producing from said versions outputs for the left and right transducers in the form of different direction-signifying transforms in accordance with the effect of the listener being disposed in the respective sound paths being simulated.

Claim 10

The auditorium simulator of claim 5 wherein connections route a given version of said signal through listener simulating means associated with each of said outputs, the versions of said signals reaching said two outputs being different due to said differing direction-signifying transforms.

Claim 11

The auditorium simulator of claim 5 wherein the source of the sound in the auditorium to be simulated has substantial stage width and said sumulator is constructed to simulate an image of said source reflected from a selected side wall of the auditorium and wherein, for the ear which is on the isde of the head remote from the wall from which the sound is simulated to arrive, said listener simulating means comprises a delay means for introducing a delay of less than a millisecond, corresponding to the difference in distance of the two ears of the listener along the path being simulated, a head shadow filter and a pinna-effect filter, and wherein the listener simulating means for the ear nearer said wall comprises a pinna-effect filter.

Claim 12

The auditorium simulator of claim 5 wherein each of said delayed versions of the signal passes through an altering means comprising an attenuator for decreasing its energy on the basis of the length of its respective path, thence to a summing point, for summing with the remaining versions, thence to a reflection filter means for decreasing the energy of the summed signals on the basis of loss due to frequency-selective absorption at the reflecting surface, thence branching to each listener simulating means, thence to the respective transducer.

Claim 13

The auditorium simulator of claim 5 wherein the source of the sound in the auditorium to be simulated is a point source and said simulator is constructed to simulate an image of said source reflected from a selected side wall of the auditorium, the listener simulating means for each of the listener's ears receiving an equally delayed version of the signal from said source to represent said image.

Claim 14

The auditorium simulator of claim 5 and further including means for altering said delayed version in accordance with the respective sound path comprising an attenuator for decreasing the energy of the signal on the basis of the length of the simulated path and a reflection filter means for decreasing the energy of the signal on the basis of loss due to frequency-selective absorption at the reflecting surface.

Claim 15

The auditorium simulator of claim 5 wherein said delay means comprises a tapped delay line.

Claim 16

The auditorium simulator of claim 5 wherein for a given simulated path, said pinna-effect filter means simulate pinna response at the angle of incidence of said given path upon the listener.

Claim 17

The auditorium simulator of claim 12 including an adapter circuit for converting multiple stereo channels into two output signals that represent direct sound received by the right and left ears of a listener at the performance, said adapter comprising, for each output signal, a summing point for adding to the signal of one of said stereo channels a modified signal from an other stereo channel, and respective means comprising a time delay of less than 1 millisecond representing the time delay said listener would experience at said performance if the sound originated at the pickup point used in picking up signal for said other stereo channel, and a head shadow filter for decreasing the added signal in accordance with head shadow effect experienced by said listener at the performance under the conditions stated below.

Claim 18

The auditorium simulator of claim 13 wherein there are two of said stereo channels picked up with a microphone spacing on the order of 20 feet.

Claim 19

The auditorium simulator of claim 13 wherein there are more than two stereo channels, and a plurality of said channels are delayed, head shadow filtered and summed to provide a respective output signal.