AudioMulch - Interactive music studio

You are viewing a web version of AudioMulch's help file.

Previous Next

Settings/Preferences Dialog Box

The Settings/Preferences dialog box provides a series of pages for configuring various aspects of AudioMulch including audio driver settings, channel assignments and level meters, MIDI control and synchronization devices, network synchronisation, document switcher behavior, VST Plugins directory, low level File Streaming configuration and actions that AudioMulch performs when it starts.

On Windows you can access the Settings/Preferences dialog box by choosing Settings... from the Edit menu or by pressing the F4 function key.

On Mac OS you can access the Settings/Preferences dialog box by choosing Preferences... from the AudioMulch application menu or by pressing command-, (command-comma).

You can show a specific page by clicking on it in the list at the left side of the dialog box. Each page is described in detail below.

Note: Changes to settings within the Settings/Preferences dialog only take effect once you have clicked Apply or OK.

Audio General

Sample rate

The Sample rate drop down list contains a complete list of the sample rates supported by AudioMulch (22.05 kHz, 32 kHz, 44.1 kHz (CD quality), 48 kHz, 64 kHz, 88.2 kHz, 96 kHz, 192 kHz). When first installed AudioMulch will default to 44.1 kHz (CD quality). The higher the sample rate selected the higher the audio quality - and CPU load.

Once selected the sample rate applies globally to all documents.

Note: Your audio interface might not support all sample rates that AudioMulch does. It is important that you consult your audio interface documentation to confirm the compatibility between software and hardware settings.

Dither output

When checked, the Dither output checkbox enables Dithering, a process that introduces a small amount of noise to improve the percieved sound quality of very quiet output signals.

Audio Driver

The Audio Driver page allows you to select a driver type and configure settings specific to that driver type.

On Windows, AudioMulch supports the use of ASIO, DirectSound and Windows Multimedia audio drivers. On Mac OS AudioMulch supports Apple's Core Audio drivers.

Driver Type

The Driver Type drop down list lists the Driver Types supported by AudioMulch. The other settings displayed on this page depend on which Driver Type is selected. Note that some audio interfaces only support certain driver types.

Driver Settings

The Driver Settings section of the Audio Driver page allows for the selection of Devices and configuration of their associated settings. When using ASIO drivers, the selected Device handles both input and output, with DirectSound and Core Audio you can select input and output devices separately. The devices selected here determine the devices available in the Audio Input, Audio Output and Sound File Preview pages. In the case of Windows Multimedia drivers all devices are always available on these pages.

Buffer Size and Number of Buffers

To provide seamless audio output, AudioMulch continuously streams a number of buffers to and from the audio device(s). The number and size of these buffers can be changed using the Buffer Size and Number of Buffers drop down lists.

The Buffer Size and Number of Buffers parameters affect the total audio latency (time delay) of AudioMulch when generating or processing sound. Some driver types allow both the Buffer Size and Number of Buffers to be adjusted whereas others allow only the adjustment of Buffer Size.

Depending on the speed of your system and the quality of your audio interface and drivers, different values for the Buffer Size and Number of Buffers settings will be optimal. If desired you can experiment to determine the lowest working values on your system by reducing both buffer size and number of buffers until the audio output begins to break up with clicks and gaps.

The buffer options available for configuration within the Settings/Preference Dialog may be constrained when using some ASIO drivers. When this occurs AudioMulch will automatically display the audio interface's currently configured buffer settings. These values cannot be edited from within AudioMulch but should be accessible within the ASIO control panel of your audio interface (see below).

For more information on the optimisation of audio buffer settings please consult the Optimising Real-Time Performance section of this help file.

Control Panel

(ASIO only)

The Control Panel... button, located on the right of the Audio Driver tab, launches the control panel of the currently selected ASIO driver. All ASIO driver control panels are different. Often they allow the configuration of buffer settings and may support other driver-specific settings. It is important to note that any changes made within the ASIO driver control panel will not be reflected in the AudioMulch Settings Dialog until you click the Reset Audio button, located on the bottom right of the AudioDriver tab.

Reset Audio

(ASIO only)

The Reset Audio button re-initialises the audio engine at the core of AudioMulch. In a process similar to closing and re-opening AudioMulch all audio settings are re-scanned to ensure that any updates or changes made within other programs or control panels have been applied.

Open all channels

(ASIO only)

The Open all channels checkbox can be used to force AudioMulch to open all channels of the selected hardware device. When unchecked, AudioMulch will only open the audio channels used by the current document (based on which SoundIn, AuxIn, SoundOut and AuxOut contraptions are present in the document).

By default, Open all channels is selected for maximum hardware device compatibility but it may introduce additional CPU load, and prevent sharing of the device between multiple clients (this will only apply when a multi-client driver is available for the selected hardware device).

If the selected audio device functions properly with Open all channels unchecked there is no significant advantage to enabling this setting.

Overdrive

(Windows Multimedia only)

The Overdrive checkbox allows you to trade off performance for stability under marginal conditions. When checked, AudioMulch will give stable real-time output priority even when the CPU load is high (approaching or beyond 100%). When audio production is given high priority the user interface may become sluggish and could even freeze. Unchecking the overdrive checkbox may result in less stable audio output when the CPU load is high, but guarantees that the program will not freeze.

It is recommended that Overdrive be disabled except when using documents that are known not to overload the computer (ie. those that dont exceed 85% CPU Load).

Audio Input

AudioMulch supports up to 256 channels of real-time audio input using 128 stereo pairs provided by the SoundIn and AuxIn1-127 contraptions. Obviously, this is of most use to users running multi-channel audio interfaces.

The Audio Input Devices and Channels grid allows you to select which audio interface devices and channels are used by which audio input contraptions.

Clicking on cells in the device column reveals a drop down list displaying all available devices. Clicking on cells in the columns labelled Left and Right allows selection of device channels used as the contraption's left and right outputs respectively.

When you change the Driver settings in the Audio Driver tab the Audio Input tab will be configured with the available devices and input channels assigned to the corresponding input contraptions. For example, the SoundIn contraption will use input channels 1&2, AuxIn1 will use input channels 3&4 and so on. In many cases these settings will be appropriate without you needing to make changes to the Audio Input Devices and Channels settings.

As with all AudioMulch settings, experimentation may reveal a number of different uses for this routing system and users are encouraged to configure these settings to suit their specific use of the software.

Audio Output

The Audio Output settings configuration is identical to that of the Audio Input settings (see previous section) except that they apply to audio output.

Sound File Preview

The Sound File Preview tab allows for the independent routing of audio from the Play and Auto play preview features of the Select a Sound File... dialogs used throughout AudioMulch where sound files are read from or written to (SoundIn, SoundOut, BubbleBlower, Drums, LoopPlayer, FilePlayer, Export to Sound File...). This feature is provided for people running multi-channel audio who may want to monitor Sound File Previews through outputs other than their primary performance outputs. One application of this feature is in the creation of an independent headphone mix.

Sound File Preview configuration is similar to the configuration of both the Audio Input and Audio Output settings. In the relevant channel row (Channel 1 &2 for stereo files) select the desired device from the list provided, and then in the final two columns identify the device channels to which you want to direct the Sound File Previews.

Additional channel rows are provided for previewing multiple channel sound files.

Audio Input & Output Meters

The Audio Input Meters and Audio Output Meters pages allow you to select which level meters are displayed on the user interface. Each page presents a check list of audio input/output contraptions. Checking a check box causes the corresponding contraption's level meters to be displayed.

MIDI Input and Control

The MIDI Input and Control page allows you to select MIDI devices used for MIDI input and parameter control. Up to eight separate MIDI input devices may be selected using the Select MIDI Input devices grid. Each row of the grid corresponds to one of eight internally routed MIDIIn ports. When assigning a particular MIDI device for control of a contraption parameter you select its corresponding MIDIIn port within the Parameter Control dialog. MidiIn contraptions are available in the patcher for routing MIDI signals to contraptions such as VST plugins which accept MIDI input.

The same device can be used for MIDI Input and MIDI Sync (see below).

When a selected MIDI device is not turned on or not connected to your computer the grid will display "(Not Connected)" next to the device name. You can connect and/or turn on the MIDI device at any time. If a selected device is connected while AudioMulch is running you will need to disable and re-enable MIDI by selecting Enable MIDI from the Control menu or by clicking the Enable MIDI icon on the Transport toolbar before AudioMulch will receive messages from that device.

Quick-Map control change resolution

The Quick-Map control change resolution buttons let you choose which resolution (7 or 14 bit) AudioMulch will use when you perform an automatic Quick-Map MIDI controller operation using the next received MIDI message. Most control surfaces only send 7 bit control information, in which case the 7 bit option should be chosen. When using a control surface which sends 14 bit controllers, choose the 14 bit option so that Quick-Map operations automatically select a 14 bit controller. Note that this option only affects the automatically selected resolution. It is always possible to manually change the MIDI controller type later using the Quick-Map or Parameter Control windows.

MIDI Sync

The MIDI Sync page allows selection of the MIDI devices used for receiving (Chase) and sending (Generate) MIDI clock synchronisation.

Sync Offset

The Sync Offset setting is provided to allow fine tuning of the synchronisation between MIDI clock and Audio output. Depending on the combination of audio and MIDI hardware you are running, it is not uncommon to find some time delay between the two. The Sync offset setting compensates for the delay generated by the specific hardware setup. There are no recommended values here, and tuning is purely a matter of experimentation.

Network Sync

Network sync allows you to sychronise the clocks of one or more copies of AudioMulch running on different computers on a local area network (LAN). The Network Sync page contains settings that identify the computers network sync is sent to, and determine the UDP port used to send and receive sync.

The available UDP network ports are numbered from 1024 to 65535. Both the Generate network sync port of the computer generating sync and the Chase network sync port of the receiver(s) must be set to the same port number. Although the default value of 7000 is usually sufficient, if another program on any of the computers is already using this value, you will need to change the port number on all computers to a different value. For most purposes we recommend using ports above 49152.

The Generate network sync Send to address must be set to the IP address of the computer you wish to send sync to, or to the local broadcast address. For example, an IP address consisting of the subnet followed by .255 (eg. 192.168.0.255) will broadcast sync to all computers on that subnet.

Document Switcher

The Document Switcher can be controlled via MIDI. The MIDI Control Source section of this page allows you to select which MIDI Control Source (if any) will cause the Document Switcher to switch documents.

The Document Saving options allow you to choose whether AudioMulch will prompt, save or discard changes before the document is switched under MIDI Control. (When you switch documents using the mouse you will always be prompted if the document has changed).

The Display full paths checkbox determines the display format of file names within the Document Switcher's Documents Grid. When unchecked only the file name itself will be visible, when checked the full path of folders to the file will be displayed.

VST Plugins

VST Plugins folder

As explained in the VST Plugins section of this help file, VST and VST2 plugins must be placed in or installed into a specific folder for AudioMulch to find them. On Windows AudioMulch defaults to its own VSTPlugins folder, something like C:\Program Files\AudioMulch 2.0\VSTPlugins; on Mac OS it defaults to the system VST plugins folder at Hard disk/Library/Audio/Plug-Ins/VST but other locations are possible.

The VST Plugins folder setting allows you to configure this location to wherever your VST and VST2 plugins are currently installed. By using this setting it is possible to eliminate the need for duplication of plugins accross your hard disk.

To selected a different folder click Browse... and select the folder you want AudioMulch to use as its VST Plugins folder. As with the default folder, the subfolder structure of the selected folder will be reflected in the VST Plugins section of the contraptions palette and the VST Plugins submenu of the new contraptions menu.

File Streaming

The File Streaming page provides settings for fine tuning the performance of sound file recording and playback.. In general, the effect of these settings is only noticable when streaming a large number of sound file channels simultaneousy.

The default settings have been selected for reliable operation on most systems and should only be adjusted if problems are experienced while playing or recording sound files. Usually such problems will take the form of glitches in sound file playback (but not with real-time audio) and or glitches in recorded sound files.

Buffer size

This is the size of individual blocks written to and read from disk. Often there is a size which works best with a particular disk. The effect of this setting is highly dependent on the hardware and operating system used. Adjusting it up or down may improve sound file streaming performance on some systems.

Input / Output queue length

As with Buffer size, increasing the value of both the Input(playback) and Output(recording) queue lengths will assist in the reduction of disk access glitches. Importantly however, higher queue lengths may significantly increase RAM usage.

Always wait for disk access to complete

The Always wait for disk access to complete checkbox is the easiest way to ensure sound file recordings are glitch free. When checked, this setting shifts AudioMulch's priority from real-time audio to disk access. This option is most suited to situations where you are recording to a sound file through SoundOut. When this mode is enabled, the recorded file will always be free of glitches no matter how much the real-time audio breaks up. In doing so however it is necessary to reduce the reliability of the real-time audio stream making live glitching far more likely. Any sound from a real-time input such as SoundIn will also be less unreliable.

Startup Actions

The Startup Actions page determines actions to be performed each time AudioMulch starts. Some of these settings are generally useful for configuring AudioMulch, such as always enabling Audio and MIDI when AudioMulch starts. Other settings are more useful for particular situations, for example for a performance you may want AudioMulch to always start with a particular Document or Document Set loaded. This can also be useful for installations where you want AudioMulch to automatically load and play a document when it is launched.

In the General startup actions section, the Open Document setting allows you to select a document which AudioMulch will open when it starts. This corresponds to opening a document using the Open... item in the File Menu. The Enable Audio, Enable MIDI and Play From Start options correspond to items with the same names in the Control Menu.

The Document Switcher startup actions section allows you to specify a Document Set to be opened and to choose whether to enable MIDI document switching when AudioMulch starts.

MIDI and Network Sync startup actions control whether AudioMulch will chase or generate MIDI and/or Network sync when it starts. These settings correspond to items with the same names in the Control Menu.

Appearance

The appearance page allows you to choose AudioMulch's color scheme. There are two options: light and dark. The color scheme will change after you click Apply or OK.