SoundPack
3D Audio for Virtools™
The standard Virtools™ application offers a limited amount of audio features, such as playing a music file or a sound with a poor spatialization quality.
SoundPack allows you to use advanced audio features from within your Virtools ™ environment. This extension includes more than 40 new Building Blocks that may be used in your compositions in order to give a professional dimension to your audio contents. Using these new tools you’ll gain access to full featured 3D audio spatialization algorithms, high quality room simulation and standard protocols in use in the pro-audio world.
Innovation
Low latency audio outputs
By using ASIO drivers instead of standard DirectSound, SoundPack enables very low latency audio and precise synchronization with video output or tracking data. With ASIO output, Virtools™ can be used with professional audio devices. SoundPack supports all the output formats available through your ASIO compatible sound device.
High quality spatialization
SoundPack contains an audio engine capable of rendering 3D audio scenes through headphones and stereo speakers by using customisable psycho-acoustic binaural and transaural processing. Head related transfer functions can be specified by the user in an easily exportable format at any spatial precision or samplerate. The audio engine also includes a room simulator supporting a statistical reverb tail and spatialized early reflections that track the dimensions and dampening properties of the virtual room.
Professional sound communication protocols
SoundPack includes a thorough set of building blocks for managing emission and reception of commands in MIDI (Musical Instrument Digital Interface) and OSC (Open Sound Control). Virtools™ Dev can finally interact seamlessly with other audio gear and software.
Technical features
Requirements
• PC, Windows XP, Vista, Seven32
• Virtools Dev 3.5 – 4.0 – 4.1– 5.0
• Any ASIO compatible sound device or driver (including software ASIO wrappers).
Spatialization
SoundPack’s audio spatialization algorithms use numerous source-related parameters: propagation time, attenuation, relative speeds (Doppler effect). The following audio renderers are included:
• Binaural and transaural rendering : Headphones or stereo loudspeakers 3D audio rendering based upon real-life measurements.• Enhanced stereo rendering
• Multichannel and VBAP rendering : Using any circular or spherical setup of loudspeakers. A preset bank is included for standard configurations such as surround, square...
• Room effects: early reflections, reverb, occlusion and obstruction. SoundPack allows the simulation of the environmental influence upon spatial audio perception, particularly the reflections on the walls of a virtual room, as well as the filtering caused by obstacles.
Low latency audio rendering
• ASIO support• Up to 32 internal audio channels
• Output channel routing
• New in v1.0.1: Free routing of background sources is now supported.
External communication protocols
• Fully supported MIDI I/O
• OpenSoundControl (OSC) I/O
Audio generation and processing
• VST host: VSTi virtual instruments support
• Built-in effects : parametric EQ, reverb
Updates
- v1.0.8 - 2010/01/06 - Virtools 5 compatibility - Mono rendered added.
- v1.0.7 - 2009/05/18 - Improved crosstalk cancellation algorithm, for a better lateral and rear virtual sound perception, and a more balanced audio rendering
- v1.0.6 - 2008/12/30 - Longcat released a maintenance release of SoundPack, v1.0.6. A large amount of work was done on performance and CPU usage, and the release fixes a small issue with MIDI output.
FAQ
My sounds don't seem to move "smoothly"
This is probably because of a low audio block size. This can be changed in the Variable Manager under the Longcat section. Certain parameters computed from a source's 3D position, like gain and delay, are interpolated between two audio blocks. Small blocks will yield steep interpolations when your sources have a high velocity whereas long blocks will give longer and smoother transitions but with a higher latency. With a Binaural context, you can also increase the convolution window size.
My CPU load is very high but I have a rather limited number of sources
Spatialisation algorithms can be very CPU costly, especially binauralisation. If you are using early reflections on each of your sources, this can multiply the amount of sources to spatialize by 7 if each 6 walls are used (even if early reflections need slightly less ressources to render)! If your are using non mono sources (like stereo or surround WAV files) this can multiply the number of sources to spatialize by yet another factor of 2 or 5. For example, 6 Virtools Wave Sounds, each using stereo VSTis and 6 early reflections yield 84 spatialised point sources.
If you have many streamed sounds, your bottleneck may be your hard-drive, or with MP3 files, the decoding of the compressed data. Try switching your sounds to non-streamed.
As a last remark, audio rendering is done in a separate thread from the Virtools main thread. Using multicore / multiprocessor systems can lighten your CPU load.
May I use my own HRTFs?
A default HRTF bank is provided with Longcat SoundPack. The corresponding file holds the ".hrt" extension and can be loaded by using the Load HRIR building block. It is possible to define your own HRTF bank, the specifications for the binary format of HRT files being available on demand.
May I use my own cross-talk cancellation (XTC) filters?
A default XTC bank is provided with Longcat SoundPack. The corresponding file holds the ".xtc" extension and can be loaded by using the Load XTC Filters building block. It is possible to define your own XTC bank, the specifications for the binary format of XTC files being available on demand.
How do I configure my own speaker setup?
A set of standard VBAP preset files are provided with Longcat SoundPack can be found in the VBAP folder of the installation directory. These files are XML files and are good examples on how to make your own VBAP speaker setups.
How do I add acoustical presets (reverb, materials, etc) ?
A set of reverb, wall material and room acoustics preset files are provided with Longcat Soundpack and can be found in the installation directory under Room Acoustics. They hold respectively the .lcrv, .lcmt and .lcro extension and can be loaded using the Load Room Wall Material Preset, the Load Reverb Preset and the Load Room Acoustics Preset building Blocks. As these files are XML files, you can easily create your own preset files, but make sure their location is listed in the corresponding section of Virtools Path Manager.
Can my sound instances have different room acoustic settings?
Sound instances are created with the Play Sound Instance BB and with the room acoustics settings (ER, ER level and reverb send) of their original sound at the time of their instanciation. If you want each instance to have different settings, just modify the original sound accordingly before calling the Play Sound Instance BB. This is also true for occlusion / obstruction settings.
Some Wave Sounds with attached VST instruments are not available in the VST Editor
Make sure that the Streamed option is activated in the sound setup of all Wave Sounds with a VSTi source.
Wave Sounds with attached VST instruments fail to load when opening a composition
When a Virtools composition containing Wave Sounds is loaded, corresponding sound files must be included in Virtools Resources or be located in one of the folders listed in Virtools Path Manager under the Sound Paths category. Therefore make sure that your VSTi DLL files are properly located.
I've sent MIDI Note On events to my VSTi Wave Sound but no sound can be heard?
You should check if the Looped option is activated in the sound setup of your Wave Sound and that the VSTi has been correctly loaded. Finally you should check if you have added a Parameter In of type WAVESOUND to your Write Midi behaviour. Not doing so will result in sending the MIDI events to your default MIDI output device instead of the underlying VSTi.
In the Variable Manager, I want to select the ASIO Digidesign Driver as the current audio device, but Virtools displays the following message in the Event Log : "Failed to open device ASIO Digidesign Driver - ASIO buffer creation failed"
This is one Longcat SoundPack known issue. When it occurs, leave the ASIO Digidesign Driver selected in the Variable Manager, close Virtools and launch it again. This will make Longcat SoundPack initialized with the ASIO Digidesign Driver.