Patent Publication Number: US-2004044804-A1

Title: System and method for audio control

Description:
PRIORITY CLAIM  
     [0001] This application claims priority benefit under 35 USC 120 to co-pending U.S. Patent Application entitled “System and Method for Audio Control,” Ser. No. 09/439,937, filed Nov. 12, 1999. 
    
    
     
       RELATED APPLICATION  
       [0002] This application is related to co-pending U.S. Patent Application entitled “System and Method for Audio Control,” filed Sep. 2, 2003.  
       TECHNICAL FIELD OF THE INVENTION  
       [0003] This invention relates to information handling systems, specifically to a system and method for audio control.  
       BACKGROUND OF THE INVENTION  
       [0004] Information handling systems or computers are commonly used with sound cards to provide audio capability. Such sound cards are typically used in conjunction with an operating system and music application software. These sound cards have a coder/decoder or analog-to-digital and digital-to-analog conversion capability. Such a capability allows translation between the digital signals utilized by the computer and analog input or output audio signals. Computer users can thus record and enhance analog audio signals by utilizing the music application software to further process the digitized audio signals or by mixing in other digital or digitized signals. In this way, users can produce multi-media products such as music, advertisements, and sound effects for playback or for storing to mass media for distribution.  
       [0005] This type of computer-based sound card audio input and output system has typically suffered from a number of disadvantages. For example, these systems suffer from the disadvantage that additional adapters are required in order to use a number of components required to simultaneously proof and monitor a production of a multi-media product. For example, the use of high fidelity microphones such as XLR type low impedance microphones, line-level inputs, and MIDI inputs and outputs requires additional adapters.  
       [0006] One approach, described in U.S. Pat. No. 5,630,175, provided for adding audio inputs into a stereo computer system. This design requires the use of an additional sound card. Another disadvantage to this approach is that the microphones that may be used with such a system are limited to those that are low-fidelity or low quality. In an effort to overcome these disadvantages, audio mixing consoles must be used to preamplify low impedance microphone inputs or to use more than one input simultaneously. For example, in order to mix a microphone and a guitar into a recording, an audio mixing console must typically be used. Yet another disadvantage is that this approach does not provide a way to hear the playback or a way to control the music application software while away from the computer. Another disadvantage is that this approach may not effectively isolate signals from the sound card, and a user may not monitor and playback the same stereo inputs and outputs while recording, without re-recording the combined signals output from the sound card through the input of the sound card.  
       [0007] Therefore, a need has arisen for a system and method for audio control that overcomes the disadvantages and deficiencies of the prior art.  
       SUMMARY OF THE INVENTION  
       [0008] In accordance with the present invention, a system and method for audio control are provided which may substantially eliminate or reduce the disadvantages and problems associated with prior devices used in controlling audio input and output.  
       [0009] The present invention comprises an adapter that provides a convenient and easy-to-use means for controlling audio input and output for recording. In accordance with one aspect of the invention an audio control system has a first input, each adapted to receive a high fidelity microphone, such as a low impedance microphone, and a second input adapted to receive a musical instrument. The system also has at least two outputs, each adapted to transmit analog signals to an input of a sound card of a computer, and electrical circuitry coupling the inputs to the outputs.  
       [0010] In another embodiment, the system has an additional input adapted to receive analog signals from an output of the sound card, and at least one additional output adapted to transmit analog signals to a receiver together with electrical circuitry coupling the additional input to the additional output. The electrical circuitry is operable to transmit analog signals from the first and second inputs to the receiver and to the input of the sound card, the electrical circuitry further operable to resistively isolate the analog signals transmitted from the output of the sound card from the input of the sound card.  
       [0011] In another embodiment, the system has a controller input adapted to receive a recording controller, and a controller output adapted to couple to the computer together with electrical circuitry coupling the controller input to the controller output.  
       [0012] In accordance with another aspect of the present invention, a method is disclosed for controlling audio input and output. The method includes coupling a first input adapted to receive a high fidelity microphone to a first channel of a sound card of a computer. The method then couples a second input adapted to receive a musical instrument to a second channel of the sound card. In a further embodiment, the method further comprises coupling a MIDI device to the computer.  
       [0013] The present invention may also permit playback while recording, while eliminating feedback of combined signals output from the sound card back to the input of the sound card, so that they are not re-recorded. Another technical advantage is a method for audio control that does not rely entirely on software controls. Another technical advantage of the present invention is a method that allows the use of high-fidelity recording equipment without the need for additional complex mixing circuitry or adapters.  
       [0014] A further technical advantage of the present invention is a system that allows for remote control and monitoring of a recording session. Another technical advantage of the present invention is an adapter that permits hands-free control and quick and convenient access to inputs, outputs and controls for a recording session.  
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0015] For a more complete understanding of the present invention, the objects and advantages thereof, reference is now made to the following descriptions taken in connection with the accompanying drawings in which:  
     [0016]FIG. 1 is a block diagram of an audio control system of the present invention;  
     [0017]FIG. 2A is a front view of an audio control system of the present invention;  
     [0018]FIG. 2B a back view of an audio control system shown in FIG. 1;  
     [0019]FIGS. 2C and 2D illustrate another embodiment of an audio control system using the teachings of the present invention;  
     [0020]FIG. 3 illustrates one embodiment for a hand controller that may be used in the embodiment in FIG. 1;  
     [0021]FIG. 4 illustrates one embodiment for a foot controller that may be used in the embodiment in FIG. 1;  
     [0022]FIG. 5A illustrates a preferred embodiment for electrical circuitry that may be used to couple inputs to outputs for channel one of an audio input and output adapter;  
     [0023]FIG. 5B illustrates another embodiment for electrical circuitry that may be used to couple inputs to outputs for channel one of an audio input and output adapter;  
     [0024]FIGS. 6A and 6B illustrate a preferred embodiment for electrical circuitry that may be used to couple inputs to outputs of an audio input and output adapter; and  
     [0025]FIGS. 7A and 7B illustrate one embodiment for a headset and electrical circuitry that may be used in the embodiment in FIG. 1.  
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     [0026] The present invention and its advantages are best understood by referring to FIGS.  1 - 7 B of the drawings, like numerals being used for like and corresponding parts of the various drawings.  
     [0027]FIG. 1 is a block diagram of an audio control system of the present invention. Audio control system  10  comprises a standard computer  20  coupled to audio input and output (I/O) adapter  40 . Various audio input devices such as a high-fidelity, low impedance microphone  110 , high-fidelity, high impedance device  120  such as a microphone, phonograph input, or musical instrument for example a guitar, and Musical Instrument Digital Interface (MIDI) piano keyboard  60  are coupled to computer  20  through audio I/O adapter  40 . Similarly, audio out devices, such as stereo headphones  80 , 100  are also coupled to computer  20  through audio I/O adapter  40 . Foot controller  51  and hand controller  52  control the operation of system  10  via audio I/O adapter  40 . Headset  700  may also be coupled to computer  20  through audio I/O adapter  40 . Audio control system  10  allows a user to quickly and conveniently access many of these inputs, outputs, and controls at the front of computer  20  or audio I/O adapter  40 . These inputs, outputs and controls are discussed below in further detail.  
     [0028] Computer  20  includes such typical components as standard sound card  30 , processor  25 , memory or disk storage  23 , mouse  35 , keyboard  36 , and monitor  45 .  
     [0029] Audio I/O adapter  40  is described in further detail in conjunction with FIGS. 2A and 2B. A second embodiment for audio I/O adapter  40  is described in conjunction with FIGS. 2C and 2D. Controllers such as hand controller  52  and foot controller  51  are described in further detail in conjunction with FIGS. 3 and 4. Electrical circuitry used in audio I/O adapter  40  is described in conjunction with FIGS.  5 A- 6 B. Electrical circuitry used to couple handset  700  to audio I/O adapter is described in conjunction with FIGS. 7A and 7B.  
     [0030] In operation, a user can utilize audio control system  10  for recording by controlling computer  20 , utilizing a compatible operating system and music application software. For example, the user may simultaneously record guitar, voice, and a MIDI input such as trumpets. The user may do so by selecting an internal soundbank or soundfont in the music application software using MIDI keyboard  60 , mouse  35 , or ASCII keyboard  36 , while viewing monitor  45 .  
     [0031] For example, the user may releasably couple a musical instrument such as guitar  120  and high-fidelity, XLR microphone  110  into front view of chassis  200  of audio I/O adapter  40 , as shown in FIG. 2A. Audio control system  10  permits the user to hear and monitor the voice, guitar, and trumpets being recorded by means of stereo headphone  80 , which is releasably coupled to audio adapter  40 . In this embodiment, guitar  120  will be heard on one side (channel one) and the voice on the other (channel two). Then, for example, trumpets from MIDI keyboard  60  may be heard in both channels of headphone  80 .  
     [0032] The user can also control recording of such audio inputs without being seated near computer  20  by using suitable controllers, such as foot controller  51  and hand controller  52 . For example, to playback, undo, or edit the recording after the session is finished, either hand controller  52  or ASCII keyboard  36  may be used in conjunction with mouse  35  and monitor  45 . Hand controller  52  and foot controller  51  are discussed in further detail in conjunction with FIGS. 3 and 4. The user can also perform telephone calls without being seated near computer  20  by using headset  700 , which is discussed in further detail in conjunction with FIGS. 7A and 7B.  
     [0033] It is within the scope of the invention for audio control system  10  to permit more than one user to simultaneously record and monitor a recording session. In addition, the user may record additional instrument tracks that may later be edited into the recording. Further, other embodiments of audio control system  10  may permit simultaneous recording of multiple instruments such as guitar  120 . The user may use audio control system  10  to make an audio recording that can be saved on any suitable storage media device, including, but not limited to CDs, and other suitable optical and magnetic media. Such suitable devices may be coupled to computer  20  and may include devices that are adapted to receive videos, cassettes, CDs, or other mass media storage systems. Coupling of such devices to computer  20  is discussed in further detail in conjunction with FIG. 6.  
     [0034]FIGS. 2A and 2B show front and back views of one embodiment of audio control system  10  of the present invention. Audio I/O adapter  40  has digital control inputs such as MIDI IN  206 , audio inputs such as LO Z  209 , Hi Z  210 , audio outputs such as stereo headphone jacks  208 , readouts  212 ,  230  and various control switches  207 ,  270  and  280 , all of which are integrated into the chassis  200  of computer  20 , as shown in FIGS. 2A and 2B. Computer  20  has electronic control cards  202 , CD ROM drive  204 , and disk drive  203 . Electronic control cards  202  include motherboard  214 , sound card  30 , and various other application specific cards  218 ,  220  and  222 .  
     [0035] It is also within the scope of the invention for audio control system  10  to comprise an audio I/O adapter  40  which is not integrated with computer  20 . Audio I/O adapter  40  as shown in FIG. 1 also comprises a plurality of inputs and outputs adapted to transmit signals to and from computer  20  (not explicitly shown), and electrical circuitry coupling the inputs to the outputs (not explicitly shown). Such inputs and outputs and circuitry are discussed in conjunction with FIGS.  5 A- 6 B.  
     [0036]FIG. 2A is a front view of audio control system  10  of the present invention. Computer  20  typically includes data control inputs  205  for releasably coupling to mouse  35  and keyboard  36 . Additional devices such as hand controller  52  and foot controller  51  can also releasably couple to input  205 . Headset  700  may also releasably couple to an input  701 (not explicitly shown), as discussed in conjunction with FIGS. 7A and 7B. The user may use CD ROM drive  204  and/or disk drive  203  for reading or writing to and from audio control system  10 .  
     [0037] In this embodiment, audio adapter  40  comprises a plurality of inputs, outputs and readouts for a first and a second stereo channel of audio I/O adapter  40 , channels one and two. Each of the inputs  206 ,  209 , and  210  comprises a receptacle adapted to releasably couple to a suitable analog or digital audio input device. Such receptacles are known to those skilled in the art. For example, digital input  206  may releasably couple to MIDI piano keyboard  60 , and inputs  209  may releasably receive high-fidelity, balanced and non balanced low impedance microphones  110  for channels one and two. One such microphone  110  may be an XLR type.  
     [0038] Similarly, audio input  210  may releasably receive high-fidelity, balanced and non balanced high impedance microphones, as well as musical instruments such as guitar  120  for channels one and two. Audio input  210  desirably provides a wide range of gain control to accommodate such input devices. In this embodiment, inputs  210  are standard one-quarter inch phone jacks that may releasably receive suitable devices for providing high quality audio inputs.  
     [0039] Audio receivers such as for example, stereo speakers or headphones  80  and  100  can releasably couple to audio outputs  208 . Outputs  208  may be any suitable receptacles, such as standard stereo headphone jacks for providing two-channel playback capability. The user may control the volume of audio playback into headphones  80  and  100  by any suitable control switch, such as rotatable knobs  207 .  
     [0040] In this embodiment, separate and identical readouts  212  provided for monitoring and controlling desired gain and volume in channels one and channel two. Thus, knobs  270  and  280  control the audio input volume and gain, respectively.  
     [0041] One embodiment for readouts  212  is a standard volume unit (VU) decibel meter. Such meters enable the user to visually verify and control desirable volume and gain for a channel. Readout displays can be graphically changed by switch  263 , audio overload or clipping is verified by indicators  230 , and may be reset by button  262 . Any suitable readout  212  such as a VU meter may be used for its ease and accessibility. Such readouts do not take up display space on monitor  45 , and are not as sluggish to respond as software-controlled meters. Such readouts can be controlled by a number of suitable mechanical or electrical control switches, knobs, buttons, or levers.  
     [0042] The user may also select between line-level inputs  209 ,  210 , and  305 , and preamplified inputs for channels one and two, by utilizing selector switches  260 . Such inputs are discussed in further detail in conjunction with FIG. 2B.  
     [0043]FIG. 2B is a back view of audio control system  10  of the present invention. Audio control system  10  includes audio inputs and outputs, in addition to typical communication ports and elements found in computer  20 .  
     [0044] In this embodiment, separate and identical audio inputs and outputs are provided for channels one and channel two. Each of the audio inputs and outputs  301 - 306 ,  381 ,  380  comprises a receptacle adapted to releasably couple to a suitable digital audio control input or output device. Such receptacles are known to those skilled in the art. For example, input/outputs  380  and  381  provide two-way MIDI communications to audio control system  10 .  
     [0045] Audio inputs  301 ,  305  are adapted to releasably receive suitable line-level audio inputs that are typically used for signals that need not be processed or amplified for gain or volume adjustment. Similarly, inputs  303  provide the user the capability to receive audio input from an external sound card (not explicitly shown). Similarly, outputs  302 ,  304 , and  306  releasably couple to suitable line-level audio outputs. Outputs  302  may releasably couple to line-level combined audio output signals, which are summed and may be subject to minimal cross-talk noise in pre mix stages, so that the user may monitor them, for example, with stereo headphones  80 . In this embodiment, all of these inputs and outputs are standard phono jacks.  
     [0046] It is within the scope of the invention to include additional inputs and outputs  390 ,  205  to provide for additional monitors  45 , mouse  35 , keyboards  36 , hand controllers  52  and foot controllers  51 . Such additional devices facilitate ease of recording and control of music application software at a separate location from computer  20 . It is also within the scope of the invention for audio I/O adapter  40  to include suitable inputs and outputs that are compatible with wireless technology. For example, one embodiment for audio I/O adapter  40  may include an infrared detector to permit wireless coupling of a suitably-adapted wireless mouse  35  to audio I/O adapter  40 .  
     [0047] A plurality of communication input/outputs provides releasable coupling for suitable standard input and output communication devices to audio I/O adapter  40 . For example, audio I/O adapter  40  supports a parallel printer at port  352   a , a SCSI input/output bus at port  351   a , and serial communications at ports  350   a  and  353   a . Ports  350   a  and  353   a  utilize universal and asynchronous receiver/transmitter (UART) circuitry. At least two monitors  45  may be releasably coupled to video input/outputs  390 .  
     [0048]FIGS. 2C and 2D illustrate front and back views, respectively, for another embodiment of audio I/O adapter  40 . Similar to the embodiments shown in FIGS. 2A and 2B, this embodiment of audio I/O adapter  40  includes audio inputs such as LO Z  209 , Hi Z  210 , audio outputs such as stereo headphone jacks  208 , readouts  212  and various control switches  260 - 280 , all of which are integrated into a chassis  200 A.  
     [0049] Audio I/O adapter  40  may releasably couple to sound card  30  of computer  20  (not explicitly shown) at stereo receptacles  660 A and  670 A. Inputs and outputs  660  and  670  to sound card  30  are further discussed in conjunction with FIG. 5A. Audio I/O adapter  40  may also releasably couple to input/output  610  of computer  20  at receptacle  610 A for MIDI input and output. MIDI interface circuitry is further discussed in conjunction with FIG. 6A. Computer  20  has electronic control cards  202  which include motherboard  214 , sound card  30 , and various other application specific cards  218 ,  220  and  222 .  
     [0050] This embodiment may comprise a subset of the inputs and outputs that were discussed in conjunction with FIGS. 2A and 2B. In this embodiment, a user may utilize audio inputs  209 - 210  and similarly monitor recording of audio signals by utilizing readouts  212 ,  230  and controls  260 - 280 . One stereo headphone  80 , which releasably couple to output  208 , may be controlled by knob  207 . Inputs and outputs  301 - 306  are standard phono jacks and operate as discussed in FIG. 2B.  
     [0051] Similarly, inputs  205  support a plurality of mouse  35 , keyboards  36 , foot controllers  51  and hand controllers  52 . It is also within the scope of this embodiment to include suitable inputs and outputs that are compatible with wireless technology.  
     [0052] In the embodiments as shown in FIGS.  2 A- 2 D, audio I/O adapter  40  may be enclosed by any suitable chassis  200  or  200 A, such as those used in the manufacture of typical computers, of sufficient size for a plurality of audio inputs, outputs and controls. It is within the scope of the invention for audio I/O adapter  40  to comprise as few or as many inputs, outputs, and peripherals such as mass storage devices and monitors as are needed to support a user&#39;s needs. As another example, audio I/O adapter  40  may also be used with a laptop computer  20 .  
     [0053]FIG. 3 illustrates one embodiment for a controller such as hand controller  52  as shown in the embodiment in FIG. 1. In this embodiment, hand controller  52  is generally rectangularly-shaped and includes a plurality of controls and buttons. Such controls and buttons may be hard-wired or programmable, and allow the user to control audio control system  10  while making a recording without the need to be located near computer  20 . Such a controller facilitates recording while using audio input and adapter  40 , especially for persons who may be disabled or who are recording a solo session. The user may utilize hand controller  52  to playback or undo a recording, or edit unwanted pops or noises. In conjunction with this process, the user may also utilize monitor  45  and software in computer system  20 .  
     [0054] Hand controller  52  may be releasably coupled to audio I/O adapter  40  at receptacle  205  by means of data control cord  460 . In this embodiment, hand controller  52  includes six keys or switches  500  through  550 . These six switches may be assigned standard recording functions to control application software used in audio control system  10 . Switches  500  through  550  permit the user to perform standard recording functions such as rewind, record, stop, pause, fast forward, and play. Switches  500  through  550  may be any standard mechanical or capacitive type switches.  
     [0055] Hand controller  52  may also include a plurality of user-assigned, software programmable keys. In this embodiment, switches  470  through  490  are such user-assigned, software programmable keys. These keys may be assignable to perform short cuts, macros, or any other software function that the user may typically utilize in operating application software in audio control system  10 . Similarly to buttons  500  through  550 , keys  470  through  490  may be any standard mechanical or capacitive type switches.  
     [0056] It is also within the scope of the invention for hand controller  52  to be electrically coupled to audio I/O adapter  40  by means of any suitable wireless circuitry. Hand controller  52  may also be voice controlled. Hand controller  52  may be any shape, and suitably large to accommodate any number of desired switches and controls.  
     [0057]FIG. 4 illustrates one embodiment for a controller such as foot controller  51  as shown in the embodiment in FIG. 1. Foot controller  51  enables a user to perform basic recording functions without the need to directly access or be seated next to mouse  35 , keyboard  36 , or monitor  45  of audio control system  10 . Use of foot controller  51  also frees up the user&#39;s hands to perform other tasks while recording. Foot controller  51  may be releasably coupled to audio I/O adapter  40  at input  205  by means of data control cord  580 .  
     [0058] In this embodiment, foot controller  51  comprises depressible foot pedal  600 , depressible switch  590 , and data control cord  580 . Foot controller  51  is generally rectangularly-shaped. In this embodiment, depressible switch  590  corresponds to a software assigned value for record. Thus, when a user depresses switch  590 , data is transferred through data control cord  580  to instruct application software used in computer system  20  to record audio inputs once switch  590  is depressed. Similarly, when a user is done recording, the user may depress foot pedal  600 . Depressing foot pedal  600  sends data through data control cord  580  to instruct sound recording software and computer system  20  to play back a desired track.  
     [0059] It is also within the scope of the invention for foot controller  51  to be electrically coupled to audio I/O adapter  40  by means of any suitable wireless circuitry. Foot controller  51  may also be voice controlled. Foot controller  51  may be any shape, and suitably large to accommodate any number of desired controls such as buttons.  
     [0060] FIGS.  5 A- 6 A illustrate preferred embodiments for electrical circuitry that may be used in audio I/O adapter  40  to couple inputs and outputs as discussed in conjunction with FIGS.  1 - 2 D. In this embodiment, such electrical circuitry comprises input selection circuitry A, volume monitoring circuitry B, output circuitry C, MIDI interface circuitry G and peripheral interface circuitry J. Input selection circuitry A, volume monitoring circuitry B and output circuitry C are discussed in conjunction with FIGS. 5A and 5B. MIDI interface circuitry G and peripheral interface circuitry J are discussed in conjunction with FIGS. 6A and 6B. FIG. 6B illustrates typical devices that may releasably couple to the circuitry discussed in FIG. 6A.  
     [0061]FIG. 5A illustrates exemplary coupling of inputs to outputs for channel one in audio I/O adapter  40  by input selection circuitry A, volume monitoring circuitry B, and output circuitry C. In this embodiment, inputs and outputs for channel two would be coupled by separate and identical circuitry A, B, and C. Other embodiments may couple electrical circuitry for channel one to channel two. Although direct connections are illustrated for various elements, many elements may be coupled through other elements without departing from the scope of the invention.  
     [0062] Input selection circuitry A is coupled to a plurality of receptacles and to volume monitoring circuitry B. Input selection circuitry A processes audio signals received at inputs  209 ,  210 , and  305  from user-selected input devices, such as high-fidelity, low impedance microphone  110 , high-fidelity, high impedance microphone or guitar  120 , and a line-level audio device.  
     [0063] Input selection circuitry A processes input audio signals from either microphone  110  or instrument  120 . Input selection circuitry A isolates inputs  209  and  210  by means of capacitive and resistive coupling, and couples the receptacles to user-controllable gain and volume pre-amplification circuitry. The user may utilize such gain and volume pre-amplification circuitry to adjust the gain and volume of the audio signal input to inputs  209  and  210  by using devices such as knobs  270  and  280 , as discussed in conjunction with FIG. 2A. The audio signal passes through the pre-amplification circuitry, to volume monitoring circuitry B. The audio signal may also pass to output  304  for the user to monitor or for external signal effects processing.  
     [0064] Input selection circuitry A is also operable to select and process input audio signals from input  305  by a variety of methods known to those skilled in the art, such as switch  260 . Input  305  is adapted to receive a line-level audio input signal, which directly couples to volume monitoring circuitry B.  
     [0065] In this embodiment, volume monitoring circuitry B comprises an amplifier and circuitry associated with readouts  212 ,  230  and associated controls, such as a VU meter, indicators  212 ,  230 , button  262 , and switch  263 . Volume monitoring circuitry B couples inputs  209 ,  210 , and  305  to output  660  and to output circuitry C. Volume monitoring circuitry B may be any suitable circuitry that permits the user to monitor readouts of the audio inputs such as volume and gain. Output  660  is adapted to releasably couple to the analog input of channel one of sound card  30  for analog to digital conversion, and for further processing in computer  20 .  
     [0066] Output circuitry C comprises audio mixing circuitry and volume amplification circuitry. Output circuitry C is coupled to sound card  30  output  670 , which is adapted to releasably couple to the output for channel one of sound card  30 . Output circuitry C also couples outputs  660 ,  670  and volume monitoring circuitry B to outputs  208 ,  302 , and  306 . Such coupling permits the user to virtually simultaneously listen to an audio signal as it is processed from inputs  209  and  210 ,  305  through input selection circuitry A and volume monitoring circuitry B, inputs  301 ,  303 ,  305 , and  671 , and sound card  30  output  670 . The user may listen to the audio signal using any suitable amplifier, such as stereo headphones  80  and  100 , which comprise two-channel coupling for stereo sound. Output circuitry C also directly couples output  670  from the output of channel one of sound card  30  for suitable line-level output  306 . Such an output is typically a standard RCA plug, requires no volume monitoring, and is discussed in conjunction with FIG. 2B.  
     [0067] Audio mixing circuitry permits selection and amplification of signals received from volume monitoring circuitry B and from signals received from sound card  30 . The audio mixing circuitry couples such inputs through output circuitry C to outputs  302 ,  208 , and  306 . Signals are directly coupled from audio mixing circuitry to any suitable line-level output or amplified by volume amplification circuitry. Such circuitry obviates the need for an additional complex mixing console, and resistively isolates signals received from sound card  30  from the input of sound card  30 . In this embodiment, a suitably-sized resistor R 2  attenuates analog signals transmitted from sound card  30  as they are transmitted to outputs  208 ,  302 . A second suitable resistor R 1  further resistively isolates such analog signals from the input of sound card  30  by attenuating such analog signals and thus prevents them from being re-recorded at the input of sound card  30 . Similarly, R 2  attenuates signals transmitted from volume monitoring circuitry B and resistively isolates them from the output of sound card  30 .  
     [0068] Output circuitry C may also be configured to process additional signals. For example, outputs from one channel of additional sound cards (not explicitly shown) may also be processed through audio mixing circuitry at one or more inputs  671 . Further, signals may similarly be directly output to input/output  306  and directly input to input  305  for releasable coupling to such an external sound card. Additional inputs such as inputs  209 ,  210  and  305  may also be coupled through additional or similar input selection circuitry A and volume monitoring circuitry B to additional inputs  671  in output circuitry C, and to sound card input  660 . Some or all of these inputs may be, for example, summed or multiplexed as desired to sound card  30 , and are only limited by the capacity of sound card  30 . Alternatively, some or all of these inputs may also each be coupled to an additional sound card (not explicitly shown). For each additional input channel processed using additional input selection circuitry A and volume monitoring circuitry B, an additional output channel may also be utilized. For example, each such additional output channel may be coupled to output  670  of sound card  30 , or to an output of the additional sound card that corresponds to an additional input channel. In such embodiments, additional resistors R 1  and R 2  may also resistively isolate signals from sound card  30 , or an additional sound card, as previously discussed. These embodiments may provide additional flexibility in accessing sound card banks and to create custom sound banks using standard, inexpensive sound cards.  
     [0069]FIG. 5B illustrates another embodiment for electrical circuitry that may be used to couple inputs to outputs for channel one of an audio input and output adapter. In this embodiment, audio I/O adapter  40  comprises circuitry in addition to the elements described in FIG. 5A.  
     [0070] For example, in some embodiments of the invention, switch S 60  may be coupled between the input  660  and output  670  of sound card  30 , and volume monitoring circuitry B. Such a configuration allows the user to monitor both sound card  30  inputs and outputs by using volume monitoring circuitry B.  
     [0071] It is also within the scope of the invention to couple and isolate input  660  and output  670  of sound card  30  by suitable means such as resistors as an alternative to or in addition to switch S 60 . Such a suitable configuration may allow the user to sum and simultaneously monitor all the signals being processed within audio I/O adapter  40 . Other suitable isolation methods and circuitry may also be used.  
     [0072]FIGS. 6A and 6B illustrate a preferred embodiment for electrical circuitry coupling additional inputs and outputs of audio I/O adapter  40 . Such electrical circuitry comprises MIDI interface G circuitry and peripheral interface circuitry J, and couples the remaining inputs of audio I/O adapter  40  to the remaining outputs. MIDI interface circuitry G couples input/output  610  to input  206 , which is adapted to receive MIDI devices such as piano keyboard  60 . Peripheral interface circuitry J couples to output  625  inputs  205 , which are adapted to receive additional keyboards  36 , and hand and foot controllers  52  and  51 . Such devices are illustrated by example in FIG. 6B.  
     [0073] MIDI interface circuitry G is also operable to couple input/output  610  to a plurality of suitable MIDI devices via input/outputs  206 ,  380  and  381 . Such coupling permits additional access to other MIDI and MIDI-controlled devices. It is also within the scope of the invention for such coupling to support direct MIDI to and from the Internet via MIDI interface circuitry G.  
     [0074] In this embodiment, the electrical circuitry used in audio I/O adapter  40  also directly couples a plurality of input receptacles to outputs. For example, ports  350   a - 353   a  are coupled to outputs  350   b - 353   b , respectively. These inputs and outputs are standard I/O plugs and receptacles.  
     [0075] Peripheral interface circuitry J couples inputs adapted to receive peripherals, such as keyboard  36 , to output  625 , and further couples output  625  to computer  20  at inputs  620 ,  630  and  640 , and output  650 . For example, peripheral interface circuitry J couples to input  630  at least one input  205  a mouse  35 . It is also within the scope of the invention to couple additional devices such as mouse  35  at input  205  to input  630 .  
     [0076] Peripheral interface circuitry J couples output  625  to input  205  a keyboard  36  and a hand controller  52  and/or foot controller  51 . It is within the scope of the invention for peripheral interface circuitry J to couple additional devices such as hand controller  52 , foot controller  51 , and keyboard  36  at additional inputs  205  to output  625 . Peripheral interface circuitry J also couples a monitor  45  to inputs and outputs  640  and  650  at video input and outputs  390 .  
     [0077] It is within the scope of the invention to couple a plurality of devices through SCSI input/output bus port  351   a . Such a plurality is limited only by the processing capacity of computer  20 . Such devices include, but are not limited to, devices suitable to read and/or write a variety of media, such as production-quality tape, compact disk, floppy drive media storage, and mass storage. Such expandability facilitates the use of audio adapter control system  10  to make sound recordings on a large scale, and on production-quality media. Such a configuration also envisions the use of audio control system  10  with standard media devices available to most consumers, utilizing technologies as they become available.  
     [0078] Furthermore, it is also within the scope of the invention to couple additional controls, peripherals, and audio and digital input and/or output channels to audio control system  10 . For example, additional monitors  45 , keyboards  36 , mouse  35 , and hand and foot controllers  52  and  51  are also within the scope of the invention. Such expansion is limited only by the underlying software and hardware.  
     [0079] Other types of processing and input/output may also be used, such as optical processing and optical buses. Microphone inputs such as  209  and  210  may have phantom power. Audio control system  10  may also be used to perform cancellation functions, which include, for example, removing lead vocal data from recorded stereo soundtracks. Audio control system  10  may also comprise additional controls such as parametric equalizers, tone controls, compressor or limiters, effects, and routing.  
     [0080]FIGS. 7A and 7B illustrate one embodiment for a headset and electrical circuitry that may be used in the embodiment in FIG. 1. Headset  700  enables a user to communicate using voice communication such as answering a telephone call, without the need to directly access or be seated next to mouse  35 , keyboard  36 , or monitor  45  of audio control system  10 , and frees up the user&#39;s hands to perform other tasks.  
     [0081] In this embodiment, audio I/O adapter  40  comprises adapter  710 , volume monitoring circuitry B 2 , and switches  720  and  721 , in addition to the elements discussed in detail in FIGS. 5A through 6A. Switch  720  couples output  730  of adapter  710  to volume monitoring circuitry B and to the analog input of channel one of sound card  30  for analog to digital conversion, and for further processing in computer  20 . Similarly, switch  721  couples the output of channel one of sound card  30  to volume monitoring circuitry B 2  and to input  731  of adapter  710  to process incoming caller signals. As illustrated in FIGS. 7A and 7B, switches  720  and  721  are set to communicate with stereo headset  700 .  
     [0082] Adapter  710  comprises at least one standard audio input  701  to releasably couple to a suitable analog audio input device such as a suitable multi-pin jack. Adapter  710  may also comprise one or more additional controls such as buttons or switches  702  and  703 , to provide suitable or user-programmable functions such as call screening or blocking. It is also within the scope of the invention for adapter  710  to comprise a standard hook and cradle device (not explicitly shown) device to connect to a standard telephone receiver, in addition to or as an alternative to headset  700 . Adapter  710  comprises suitable volume amplification circuitry to process audio signals to and from sound card  30  at output  730  and input  731 , respectively. Adapter  710  also comprises suitable logic coupled to switches  720  and  721  and to output  625 , which may in some embodiments be coupled to computer  20  at input  620 , as illustrated in FIG. 6A. Adapter  710  may also comprise or be coupled to suitable interface circuitry  736  to process signals to and from input  731  and outputs  625  and  730 .  
     [0083] Headset  700  may be releasably coupled to audio I/O adapter  40  at input  701  by means of a suitable data control cord  704 , or may be wirelessly coupled to audio I/O adapter  40 . In this embodiment, headset  700  may be any suitable device allowing voice communication, such as a headset as illustrated in FIG. 7B, or a standard telephone receiver.  
     [0084] In operation, headset  700  may be activated for example, to receive or place a voice call. One embodiment of the invention may include a sensor  750  coupled to adapter  710  to control switches  720  and  721 . Sensor  750  may also be coupled to adapter  710  by means of control cord  704 . Sensor  750  may sense a user&#39;s presence and inductively activate headset  700 . Activation of headset  700  may invoke adapter  710  to mute the output of other audio and digital signals present in system  10 , and may further activate computer software through output  625 . Adapter  710  processes audio signals received through adapter  710  and switch  720  at output  730 , and receives audio signals through switch  721  at input  731 , respectively. It is also within the scope of the invention for adapter  710  to comprise suitable logic to redirect signals of other devices to headset  700 , or to make all inputs and outputs simultaneously active. Such logic may be implemented in software, firmware, or hardware, and may be, for example, manually controlled, to predefine or select redirection to headset  700  of any number of additional controls, inputs and outputs.  
     [0085] It is also within the scope of the invention for volume monitoring circuitry B 2  and switches  720  and  721  to reside in adapter  710 , in addition to or rather than in audio I/O adapter  40 . In such an embodiment, adapter  710  may releasably couple to audio I/O adapter  40 . Similarly, the elements comprising adapter  710  may be incorporated into audio I/O adapter  40 . For example, the embodiments as illustrated in FIGS. 2C and 2D may incorporate input  701  and switches  702 ,  703 , to couple to and control headset  700 . Similarly, volume monitoring circuitry B 2 , switches  720  and  721  and the circuitry residing in adapter  710  may also be suitably incorporated into the circuitry as illustrated and discussed in FIG. 5A.  
     [0086] While the invention has been particularly shown and described by the foregoing detailed description, it will be understood by those skilled in the art that various other changes in form and detail may be made without departing from the spirit and scope of the invention.