Process for high fidelity sound recording and reproduction of musical sound
View Patent ↗A local performance simulation system simulates an ensemble sound pattern. The simulation system includes a signal generation system for simultaneously generating contact recording signals based on vibrations from the ensemble, where the ensemble produces an ensemble sound pattern. A signal processing system channelizes the contact recording signals and generates final instrument signals based on the channelized contact recording signals. The simulation system further includes a reproduction system with dedicated loudspeaker systems for generating audible sound waves based on the final instrument signals, where the sound waves simulate the ensemble sound pattern. Contact recording the vibrations and channelizing the contact recording signals eliminates all reverberation and reflection effects of the recording environment from the contact recording signals. Using a dedicated loudspeaker system for each instrument in the ensemble allows the simulation system to capture the reflection and reverberation effects of the listening environment, and creates the impression that the ensemble is present in the listening environment.
1. A sound reproduction system, comprising:
a first multi-driver speaker system having a first plurality of co-located speakers configured to emit sound in a first plurality of radial directions, thereby approximating a first frequency dependence of radiation from front, back and side surfaces of a first assigned instrument, wherein a front piston diameter and a rear piston diameter are chosen to respectively reproduce a forward and rear frequency dependence and polar radiation pattern of the first assigned instrument; and
a second multi-driver speaker system having a second plurality of co-located speakers configured to emit sound in a second plurality; of radial directions, thereby approximating a second frequency dependence of radiation from front, back and side surfaces of a second assigned instrument, wherein a front piston diameter and a rear piston diameter are chosen to respectively reproduce a forward and rear frequency dependence and polar radiation pattern of the second assigned instrument.
2. The system of claim 1 , further comprising:
a signal generation system for simultaneously generating contact recording signals based on vibrations from an ensemble, the ensemble producing an audible ensemble sound pattern; and
a signal processing system for channelizing the contact recording signals and generating final instrument signals based on the channelized contact recording signals.
3. The system of claim 1 wherein the ensemble includes a plurality of instruments.
4. The system of claim 3 wherein the plurality of instruments includes a string quartet.
5. The system of claim 3 wherein the signal generation system includes a plurality of contact recording configurations.
6. The system of claim 5 wherein each contact recording configuration includes a pair of contact transducers coupled to a corresponding instrument at a location governed by a cross-correlation function as measured in different frequency bands.
7. The system of claim 6 wherein the pair of contact transducers includes:
a first transducer located below an f-hole of the corresponding instrument, the first transducer generating a contact recording signal based on vibrations near the f-hole; and
a second transducer located under a bridge of the corresponding instrument, the second transducer generating a contact recording signal based on vibrations near the bridge.
8. The system of claim 1 wherein the signal processing system includes:
a storage system for storing contact recording signals to a storage medium as channelized data; and
a retrieval system for retrieving the channelized data from the storage medium.
9. The system of claim 8 wherein the storage system includes:
an analog to digital conversion system for generating digital recording signals based on the contact recording signals; and
a recording system for generating the channelized data based on the digital recording signals, the recording system recording the channelized data to the storage medium.
10. The system of claim 9 wherein the retrieval system includes:
an equalization system for tailoring a frequency response of the channelized data;
a mixing system for generating intermediate instrument signals based on the channelized data;
a digital to analog conversion system for generating final instrument signals based on the intermediate instrument signals; and
an amplifier for amplifying the final instrument signals.
11. A multi-driver speaker system comprising:
a front speaker having a front piston diameter chosen to reproduce a forward frequency dependence of and polar radiation pattern of a front surface of a particular musical instrument; and
a rear speaker having a rear piston diameter chosen to reproduce a rearward frequency dependence of and polar radiation pattern of a rear surface of the particular musical instrument,
wherein the front and rear speakers are configured to emit sound in front and rear directions in order to approximate a frequency dependence of radiation from front and rear surfaces of the particular musical instrument.
12. The system of claim 11 , further comprising a side speaker having a side piston diameter chosen to reproduce a side frequency dependence of and polar radiation pattern of a side surface of the particular musical instrument, wherein the side surface is configured to emit sound in a side direction relative to the front and rear speakers in order to approximate a frequency dependence of radiation from a side surface of the particular musical instrument.
13. A method of manufacturing a multi-driver speaker system, comprising:
choosing a front speaker to have a front piston diameter adapted to reproduce a forward frequency dependence of and polar radiation pattern of a front surface of a particular musical instrument;
choosing a rear speaker to have a rear piston diameter adapted to reproduce a rearward frequency dependence of and polar radiation pattern of a rear surface of the particular musical instrument; and
configuring the front and rear speakers to emit sound in front and rear directions in order to approximate a frequency dependence of radiation from front and rear surfaces of the particular musical instrument.
14. The method of claim 13 , further comprising:
choosing a side speaker to have a side piston diameter chosen to: reproduce a side frequency dependence of and polar radiation pattern of a side surface of the particular musical instrument; and
configuring the side speaker to emit sound in a side direction relative to the front and rear speakers in order to approximate a frequency dependence of radiation from a side surface of the particular musical instrument.