Abstract:
A foot-operated audio effects device ( 10 ) receives, stores and operates at least one software audio effect plug-in ( 86 ). At least two of the audio effect plug-in ( 86 ) may be designed to operate under different operating systems. The device ( 10 ) may receive multiple audio input streams ( 38, 40 ). Users can control at least one parameter of the audio effect plug-ins ( 86 ). The device ( 10 ) may include a mass storage device ( 72 ) which stores audio which has been generated within the device ( 10 ). In use, the device ( 10 ) may be connected to a computer ( 110 ) and software audio effect plug-ins ( 86 ) transferred to and stored in the device ( 10 ). The computer ( 110 ) may be used to configure parameters of the audio effect plug-in ( 86 ). Those parameters may be stored within the computer ( 110 ).

Description:
RELATED APPLICATION 
       [0001]    This application is based on and claims the benefit of the filing dates of AU applications nos. 2007904025 filed 26 Jul. 2007 and 2008901175 filed 11 Mar. 2008, the contents of which as filed are incorporated herein by reference in their entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to foot-operated audio effects devices suitable for stage performances or sound recording. 
       BACKGROUND OF THE INVENTION 
       [0003]    In the fields of stage performances and sound recording, audio effects are applied to the audio from musical instruments, such as an electric guitar, or vocals from a microphone. These audio effects alter the audio in a way that enhances the performance by adding audio effects such as distortion, delay or many other audio effects to the input audio stream which then enhances the final output sound. In a typical application the audio stream is input into a foot-operated audio effect device which alters the input audio stream and then the audio stream from the foot-operated audio effect device is output as an output audio stream through to an output receiving device such as an amplifier, DI box (direct input), wireless transmitter, headphones or mixing desk. 
         [0004]    Traditionally, audio effects have been applied by using foot-operated analogue single audio effect devices sometimes called “foot pedals”, “stomp boxes” or “guitar pedals”. Such foot-operated audio effect devices were analogue devices and produced only one audio effect to be applied to the audio stream. The foot-operated audio effect devices are usually operated by a foot pedal to switch the audio effect on and off, or to actuate a controllably, continuously variable audio effect such as the “wha-wha” audio effect. 
         [0005]    One limitation of such foot-operated audio effect devices is that they provide only one audio effect, which limits the performer&#39;s creativity. Sometimes a series of these foot-operated audio effect devices are used to provide a number of selectable audio effects. Such a series arrangement necessitates using an array of different foot-operated audio effect devices resulting in a complex, expensive, time-consuming and unreliable system to generate the audio effects. If any one of the foot-operated audio effects devices fails in such a complex setup, then it will produce either no sound or inferior sound. 
         [0006]    There are also foot-operated multi audio effects device sometimes called a “multi-effects foot pedal” or a “digital multi-effects pedal”. These combine a number of audio effects into one foot-operated audio effect device. They typically use digital signal processing (DSP) technology to emulate a fixed number of foot-operated analogue single audio effect devices and provide foot pedals for selecting the currently active audio effect or, to actuate a controllably continuously variable audio effect. 
         [0007]    Foot-operated multi audio effects devices are limited to a fixed number of selectable audio effects and so are not flexible or extensible. The performer is limited to the audio effects provided with the foot-operated multi audio effects device they have purchased. The DSP hardware is also often inferior in the sound quality it produces compared with the foot-operated analogue single audio effect device it emulates. 
         [0008]    There are also standard software plug-in audio effects (plug-ins) which operate through a host program on a powerful laptop computer or PC. An industry standard plug-in is the virtual studio technology (VST) plug-in. In a typical application audio stream is input to the soundcard of a computer. The performer operates the host program which applies the selected plug-in to the input audio stream. The performer may also manipulate the adjustable parameters of the plug-in. The altered audio stream is then output to an output receiving device. The host program may also be controlled by an external musical instrument data interface (MIDI) controller which is operated to select the active standard software plug-in audio effect and manipulate its adjustable parameters. 
         [0009]    A disadvantage with the plug-ins operating through a computer is that the computer is not suited to the hostile environment of live performances which can include drink spillage, moshing, or handling by roadies. Such performances involve the continual set-up and tear-down of sound equipment and travel between venues for the live performances. The sound equipment must, therefore, be rugged, but a computer is a fragile piece of equipment that is liable to be damaged by such activities and environments. Also it is not acceptable that the computer freeze-up and need rebooting during a live performance, or that a background process running on the computer cause an audio glitch as this would impair the quality of the performance. 
       SUMMARY OF THE INVENTION 
       [0010]    According to a first aspect of the present invention, there is provided a foot-operated audio effects device, adapted to receive, store and operate at least one software audio effect plug-in. 
         [0011]    The at least one software audio effect plug-in may be a standard software audio effect plug-in. The at least one software audio effect plug-in may be user-selected. 
         [0012]    The at least one software audio effect plug-in may comprise a VST plug-in. The device may comprise an X86 based effect pedal adapted to receive, store and operate at least one VST audio effect plug-in. 
         [0013]    It is preferred that the foot-operated audio effects device is adapted to receive and simultaneously store a plurality of user-selected standard software audio effect plug-ins. In this case, it is preferred that the foot-operated audio effects device is adapted to simultaneously operate at least two of the user-selected standard software audio effect plug-ins. 
         [0014]    It is preferred that at least two of the plurality of user-selected standard software audio effect plug-ins are designed to operate under different operating systems. 
         [0015]    It is preferred that the foot-operated audio effects device is adapted to receive a plurality of input audio streams. 
         [0016]    It is preferred that the foot-operated audio effects device is adapted to process at least one of the input audio streams with at least two of the user-selected standard software audio effect plug-ins. 
         [0017]    It is preferred that the foot-operated audio effects device is adapted to simultaneously process at least two of the plurality of input audio streams with one of the user-selected standard software audio effect plug-ins. 
         [0018]    It is preferred that the foot-operated audio effects device is adapted to produce at least two output audio streams. 
         [0019]    It is preferred that the foot-operated audio effects device further comprises at least one user-adjustable control that is adapted to allow the user to control at least one parameter of the software audio effect plug-in. 
         [0020]    It is preferred that the foot-operated audio effects device further comprise a mass storage device that is adapted to store audio which has been generated by application of at least one of the user-selected standard software audio effect plug-in that is stored within the device. 
         [0021]    According to a second aspect of the present invention, there is provided a method of using a foot-operable audio effects device, the method comprising: 
         [0022]    connecting an external device to the foot-operable audio effects device; 
         [0023]    transferring at least one user-selected audio effect plug-in from the external device to the foot-operable audio effects device; and 
         [0024]    storing said at least one user-selected audio effect plug-in (such as a VST plug-in) in the foot-operable audio effects device. 
         [0025]    The external device may be a computing device (such as a PC or the like), used to configure at least one parameter of the standard software plug-in. 
         [0026]    The method may comprise saving, within the external device, at least one of the parameters of the user-selected audio effect plug-in that has been configured. 
         [0027]    The method may comprise providing an application on said external device for generating an emulation of said audio effects device, said emulation being user controllable and adapted to generate configuration data that is loadable into said audio effects device and usable by said audio effects device as configuration data. 
         [0028]    The configuration data may comprise plug-in parameter settings. 
         [0029]    The configuration data may comprise settings for a group of plug-ins configured to operate together. 
         [0030]    According to a third aspect of the present invention, there is provided an audio generating or playback device, adapted to receive, store and operate at least one software audio effect plug-in (such as a VST plug-in), and to output said audio with the at least one software audio effect plug-in applied thereto. 
         [0031]    Thus, a device is provided that can generate or playback audio material (from, for example, a digital recording) with one or more audio effects applied according to the at least one (but commonly more than one) software audio effect plug-in (and not merely process an audio signal). The device of this aspect may have any of the preferred features of the first aspect. 
         [0032]    According to a fourth aspect of the present invention, there is provided a method of using an audio generating or playback device, the method comprising: 
         [0033]    connecting an external device to the device; 
         [0034]    transferring at least one user-selected audio effect plug-in (such as a VST plug-in) from the external device to the device; and 
         [0035]    storing said at least one user-selected audio effect in the device. 
         [0036]    According to a fifth aspect of the present invention, there is provided a computing device provided with or running a computer program for generating an emulation of a foot-operable audio effects device, the emulation being user controllable and adapted to generate configuration data that is loadable into the audio effects device and usable by the audio effects device as configuration data. 
         [0037]    According to a sixth aspect of the present invention, there is provided a computer storage medium provided with a computer program adapted to generate an emulation of a foot-operable audio effects device, the emulation being user controllable and adapted to generate configuration data that is loadable into the audio effects device and usable by the audio effects device as configuration data. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0038]    In order that the invention may be more fully ascertained, preferred embodiments will now be described, by way of example, with reference to the drawings, in which: 
           [0039]      FIG. 1  is a schematic top view of a foot-operated audio effects device according to a preferred embodiment of the present invention; 
           [0040]      FIG. 2  is a schematic rear view of the foot-operated audio effects device of the embodiment of  FIG. 1 ; 
           [0041]      FIG. 3  is a schematic side view of a foot-operated audio effects device of the embodiment of  FIG. 1 ; 
           [0042]      FIG. 4  is a schematic diagram of the hardware architecture of the foot-operated audio effects device of the embodiment of  FIG. 1 ; 
           [0043]      FIG. 5  is a schematic view of data-flows within the embedded software that is executed on the microprocessor of the foot-operated audio effects device of the embodiment of  FIG. 1 ; 
           [0044]      FIG. 6  illustrates the layered software architecture of the embedded software described by reference to  FIG. 5 ; 
           [0045]      FIG. 7  is a schematic view of the foot-operated audio effects device of the embodiment of  FIG. 1  connected to a laptop computer, illustrating the downloading of VST effects plugins according to a preferred embodiment of the present invention; 
           [0046]      FIG. 8  illustrates the connection of a guitar to the foot-operated audio effects device of the embodiment of  FIG. 1 ; and 
           [0047]      FIG. 9  illustrates the use of the foot-operated audio effects device of the embodiment of  FIG. 1  in a stand-alone, performance mode. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0048]      FIGS. 1 ,  2  and  3  are schematic top, rear and side views of a foot-operated audio effects device  10  according to a preferred embodiment of the present invention. Device  10  has a case in the form of a rugged, splash resistant enclosure  12 , and is designed to be placed on the floor and manipulated by foot. A continuously variable foot pedal  14  allows live control of effect parameters, for example, “wha-wha” or distortion level. Device  10  includes a ‘next’ foot-switch  16  and a ‘previous’ foot-switch  18  that allow the performer to quickly select between previously stored presets, and a third, configurable foot-switch  20  that may be configured to perform an arbitrary function appropriate to the currently selected effects plugin. For example, configurable foot-switch  20  may be configured to trigger the start and end of recording for a loop recording/playback effect. Device  10  also includes an LCD display  22  for displaying the currently selected preset and plugin names. 
         [0049]    Device  10  is adapted to receive, store and operate (that is, apply to inputted signals) a plurality of user-selected VST effect plug-ins, and to simultaneously operate at least two of the VST effect plugins. 
         [0050]    Device  10  has, positioned adjacent to display  22 , six continuously rotary control knobs  24  for adjusting additional effect parameters. For example, for a reverb effect knobs  24  could adjust: room size, brightness, decay time, frequency response and the like. Knobs  24  are positioned adjacent to display  22 , and the name of the parameter currently assigned to each knob  24 , along with the current value of that parameter, is displayed by display  22  adjacent to the respective knob  24 . 
         [0051]    Device  10  also has a set of arrow buttons  26  and a selection button  28  to allow configuration of device  10  when it is not connected to a laptop. Arrow buttons  26  and selection button  28  can be used to navigate menus displayed on display  22  for the purpose of creating and modifying presets, switching between banks of parameter-knob assignments, and the like. 
         [0052]    As is illustrated in  FIG. 2 , the back panel  30  of device  10  has an on-off switch  32 , a DC power socket  34  and a standard USB slave socket  36 . Also provided on back panel  30  are guitar input  38  and microphone input  40 , and guitar and microphone outputs  42 , 44  for the processed signals from each of guitar and microphone inputs  38 , 40 . Guitar input  38  is configurable for either piezo or magnetic pickups via the input configuration menu accessed with display  22 , arrow buttons  26  and selection button  28 . Microphone input  40  is configurable for either microphone or line level input via the input configuration menu. When the input configuration menu is being displayed on display  22 , rotary knobs  24  can be used to set the input and output gain levels for each of guitar and microphone inputs and outputs  38 , 40 , 42 , 44 . 
         [0053]      FIG. 4  is a schematic diagram of the hardware architecture  50  of device  10 . The electronic components of device  10  are mounted on a single special-purpose PCB (not shown) housed within enclosure  12 . Foot pedal  14  is connected to a continuous rotary encoder  52  which is connected to a user input conditioning module  54  whereby the position of the foot pedal is monitored by software running on a micro-processor  56 . Likewise, rotary knobs  24  are connected to encoders  58  whereby their position is monitored by micro-processor  56  via user input conditioning module  54 . Foot switches  60  are monitored via user input conditioning module  54  in a similar way. Guitar input  38  and microphone input  40  are connected to a guitar preamplifier  62  and a microphone preamplifier  64 , respectively, whereby the input signals are amplified to a level suitable for processing by an analogue to digital converter  66 . Analogue to digital converter  66  supplies the digitised input signals to microprocessor  56 , where they are processed by installed VST effect plugins. The processed signals are then sent to a digital to analogue converter  68 , the resulting analogue signals from which are sent to guitar output  42  and microphone output  44 , respectively. 
         [0054]    Hardware  50  also includes RAM  70  directly soldered to the PCB, a solid state flash storage chip  72  (though other forms of memory, such as a hard disk, may also be suitable) for storing embedded software and downloaded VST effect plugins, a power supply module  74  for conditioning DC power provided via DC input socket  34 , a display driver  76  for driving display  22 , and a USB slave interface  78  to facilitate the connection of device  20  to a general purpose PC or laptop computer via USB socket  36 . 
         [0055]      FIG. 5  is a schematic view of data-flows  80  within the embedded software that is executed on microprocessor  56 . Input from guitar input  38  and microphone input  40  is captured by the interrupt driven, kernel level, audio capture driver  82 . An embedded VST host  84  passes the audio input stream from the audio capture driver  82  to each of one or more currently active VST plugins  86  in turn. The processed audio signal is then sent to the kernel level audio output driver  88  which sends it to guitar output  42  or microphone output  44 . VST plugins  86 , which are adapted to run—in this embodiment—on an ix86 Windows PC, execute natively on the ix86 microprocessor  56 . However, plugins  86  also make Win32 API calls, which would normally be handled by the Windows (trade mark) operating system. Accordingly, device  10  includes a Win32 API Library  90  running under an embedded operating system to handle these calls. 
         [0056]    Inputs from the foot pedal encoder  52 , rotary knob encoders  58  and foot switches/buttons  60  are captured by interrupt driven, kernel level, user input driver  92 . An application logic module  94  responds to events from user input driver  92  and sends control commands to VST host  84  to: 
         [0057]    adjust parameters of currently loaded plugins  86 ; 
         [0058]    change interconnections between the currently loaded plugins  86 ; and 
         [0059]    load new plugins  86  from the VST plugin storage area (i.e. flash storage chip  72 ) into VST host  84 . 
         [0060]    Application logic module  94  also updates display  22  via kernel level display driver  76  to display the current preset, currently loaded plugins, current parameter values, menus etc. 
         [0061]    A USB mass storage driver  96  makes VST plugin storage area  72  visible on a laptop or PC that is connected via USB slave socket  36 . This allows new plugins to be loaded into VST plugin storage area  72  from the laptop or PC. 
         [0062]    Not illustrated for the sake of simplicity is the connection from the audio output driver to the USB slave socket  36 . This connection makes the audio output signal available as a class compliant USB audio input on a PC or laptop connected via USB slave socket  36 . Data outputted by user input driver  92  is also passed to USB slave socket  36  as a MIDI data stream that is visible on the PC or laptop as a class compliant USB MIDI input and can be used to control arbitrary MIDI aware software on the PC/laptop. 
         [0063]      FIG. 6  illustrates the layered software architecture  100  of embedded software described above by reference to  FIG. 5 . The software is based on an embedded operating system kernel  102  incorporating USB mass storage driver  96 , user input driver  92 , display driver  76 , audio capture driver  82  and audio output driver  88 . On top of operating system kernel  102  the remaining modules are implemented as user space applications and libraries. The application logic module  94  controls embedded VST host  84 , which controls VST plugins  86 . Application logic module  94  manages interactions with USB mass storage driver  96 , user input driver  92  and display driver  76 . Embedded VST host  84  deals with audio input and output with audio capture driver  82  and audio output driver  88 , as well as passing audio and control to VST plugins  86 . VST plugins  86  run on top of Win32 AIP Library  90  which handles the Win32 API calls that would normally be handled by the Windows (trade mark) operating system on a general purpose PC. 
         [0064]    Microprocessor  56  does not have the full range of peripheral devices that would be connected in a typical general purpose PC. RAM  70  is directly soldered to the PCB instead of SIM sockets. Flash storage chip  72  is used in this embodiment instead of a hard disk for storage of embedded software and downloaded VST effect plugins. Although display driver  76 , USB slave interface  78 , analogue to digital converter  66  and digital to analogue converter  68  are depicted as discreet modules in the figures, they are in fact incorporated into a package with microprocessor  56  to reduce chip-count and manufacturing cost. 
         [0065]      FIG. 7  is a schematic view of device  10  connected to a standard PC or Mac (trade mark) laptop  110  (or other computer, such as a desk-top PC) with a standard USB cable  112 , to illustrate the, downloading of VST effects plugins according to a preferred embodiment of the present invention from laptop  110  via USB cable  114  to device  10 . Upon the connection of device  10  and laptop  110  with USB cable  112 , a representation of device  10  is displayed by laptop  110  on its display  116 . That representation shows device  10  as a removable storage device. 
         [0066]      FIG. 8  illustrates the connection of a guitar  118  to device  10  via a standard guitar lead  120 , whereby the signal from the electrical pickup of guitar  118  is transmitted to and processed by device  10 . Device  10  modifies the signal according to the VST effects plugins  86  currently downloaded to it and the settings of its controls as set with control knobs  24 , etc. The modified signal is digitally transmitted to laptop  110  via USB cable  112 . When USB cable  112  is connected, in addition to device  10  appearing as a removable storage device as described above by reference to  FIG. 7 , device  10  appears as a USB class compliant audio input device. The audio signal received by laptop  110  can be monitored on a headset  122  or used in any desired fashion on laptop  110 . Additionally, software running on laptop  110  can be used to fine-tune the configuration of the VST effects plugins  86  installed on device  10 . This software also supports the creation of presets, which capture certain configurations of certain combinations of effects, and which can be quickly recalled later when device  10  is disconnected from laptop  110 . 
         [0067]      FIG. 9  illustrates the use of device  10  in a stand-alone, performance mode in a stage environment. Guitar  118  is connected via guitar lead  120  to device  10 , and an amplifier and speakers  124  are connected via a standard line-level audio output lead  126 . Knobs  26  and the other controls of device  10  allow the selection of plugins  86 , the recalling of previously configured presets and live modification of plugin parameters. In an alternative embodiment, audio output lead  126  is connected to a mixing desk, a DI-box or a wireless transmitter as part of a more complex sound system. 
         [0068]    In some embodiments, device  10  is configured to interface with laptop  110  to exchange configuration data. Such configuration data includes, for example, plug-in parameter settings and bank settings (that is, for groups of plug-ins configured to operate together). The exchange of configuration data with laptop  110  can be effected via USB cable  112  or a USB memory device (such as a USB ‘stick’). This exchange is facilitated by providing laptop  110  with an application (typically a software application written for the relevant operating system, such as Windows (trade mark) or Mac (trade mark)) that emulates device  10 . This application controls laptop  110  to create a software emulation of device  10  and to display a representation of device  10  on display  116  of laptop  110 ; the representation of device  10  has user-manipulable controls so that the user, by manipulating the keyboard and/or mouse of laptop  110 , can configure a complex plug-in, which may have several hundred parameters, and—once configured, transfer the resulting plug-in to device  10 . It should be noted that the emulation of device  10  is able to operate the audio hardware of laptop  110 , thereby allowing the user to test the plug-in before transferring it to device  10  by firstly playing sound with the application. 
         [0069]    A group of such plug-ins can be connected to form a plug-in bank. For example, a guitar effect bank may comprise a distortion module feeding into a delay module, which then feeds in to a “wha-wha” pedal effect. The application can be controlled by the user to create plug-ins banks on laptop  110 . 
         [0070]    Once the user has constructed one or more plug-ins or plug-in banks, and configured the desired plug-ins, the application can be controlled to construct a configuration file, which can then be transferred—as discussed above—to device  10 . Device  10  then loads this configuration file (which may also contain plug-in executable code for the plug-ins that the user desires to use), and operates in the same manner as did the emulation of device  10  emulated by the application on laptop  110 . This allows the user to, for example, create a setup in a studio using the application, transfer it to device  10 , and use it on stage with device  10 . If changes are made to a configuration file of configuration data (including plug-in parameter settings and bank settings) on device  10  while on stage, by the user controlling device  10  with typically arrow buttons  26  and selection button  28 , the updated configuration file can be transferred to laptop  110  (via USB cable  112  or a USB memory device) for use back in the studio or on another device comparable to device  10 . 
         [0071]    Modifications within the scope of the invention may be readily effected by those skilled in the art. It is to be understood, therefore, that this invention is not limited to the particular embodiments described by way of example hereinabove. 
         [0072]    Furthermore, in the claims that follow and in the preceding description of the invention, except where the context requires otherwise owing to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, that is, to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. 
         [0073]    Further, any reference herein to prior art is not intended to imply that such prior art forms or formed a part of the common general knowledge in Australia or any other country.