Instrument Modeller FAQ

Sound Synthesis project homepage

This FAQ's purpose is to answer questions that can rise during your unusual experience with Instrument Modeller application :)

You can send your questions to our e-mail, and we will try to answer as soon as possible

General questions
Q: What does "Instrument Modeller" do?
A: This is a program for creating your own unusual sounds, playing music on your own musical instruments, investigating the nature of sound and doing many more interesting things. It uses modern approach to sound synthesis - physical modelling.
Q: What kind of sounds can Instrument Modeller produce?
A: Instrument Modeller is not limited to one type of sounds. Everything depends on your imagination and on the physical model you are using. Some physical models produce better guitar-like sounds, while another ones produce drum-like.
Q: Where can I find the latest version?
A: Latest version, along with documentation and examples, can be found at our site
Introduction to sound synthesis
Q: What is physical modelling, and why it is better than other types of sound synthesis?
A: Physical modelling differs from other types of sound synthesis in way of creating sound: other types, like analog and FM-synthesis, create waveforms of sounds, while physical modelling creates the source of the sound - musical instrument, and only then reads sound from the source. Main drawback of the physical modelling is its high computational complexity.
Usage questions
Q: Why does a window pop up, when I start the program? What is "Harmonic Oscillator" and "Digital Waveguide"?
A: This window let you select a physical model you want to use. Harmonic Oscillator can produce wider range of sounds, and visualization only works in this mode. Digital waveguide is a model for creating various flute-like sounds (also some unusual sounds can be produced :) ). Most of the documentation is dedicated to the Harmonic Oscillator model, but an example of creating a flute can be found in this FAQ below.
Q: Are there any examples/tutorials on how to create sounds?
A: Examples of the sounds and graphs can be found at our site, and tutorial can be found in documentation in the tutorial section.
Also, a lot of melodies and graphs come with the file you've downloaded. Go to the directory, where you have unpacked the downloaded file, and there you will find folders graphs, instruments and snc, where you will find examples. Also, when you get familiar with the Instrument Modeller, you can go to the bin folder, and examine SNCParser and MIDIParser.
Q: Can you give a simple example - how to create an instrument? (Harmonic oscillator model)
A: First - create a graph, by clicking "Cell graph" or "Hexagonal graph" button, select the size of your graph, click "Fixed border" (so that it will not produce noise), click "OK" and place your graph somewhere. Then, click "Modify point" button, and set velocity of one unfixed (light blue) point to 1000. After that, click "Playing point" and select one of the unfixed points. Afterwards, click on the "Generate number of notes" button, and click "Generate!". After a while, notes will be generated, and stylized piano will show. Now you can play your own instrument :) Also, you can look in the folder instruments in the SDK directory.
Q: Can you give a simple example - how to create an instrument? (Digital waveguide model)
A: First - create a graph, by clicking "Cell graph". Notice that you can only create 1-dimensional graph in this model. Set a width to 4, and click in the editor window. Click "Modify point", select the left end of the graph, and set level of distortion to 0.3. Afterwards, click "Playing point" and select the right end of the graph. Then, click "Generate number of notes button" and then - "Generate!". After a while, a whistling sound will be created. Feel free to modify the parameters to create new sounds. Enjoy :) Also, you can look in the folder waveguides in the SDK directory.
Q: What is SNC and INS formats, and what for do I need them?
A: SNC and INS formats are simple texts files, used to describe instruments and melodies. INS files are used to describe instruments (as a set of notes). You can use INS files, generated by Instrument Modeller, alter them, or create your own with just a text editor. For example, if you want to create an instrument, composed of sounds, recorded with microphone, to play them in Instrument Modeller, just create your file, open it in you favorite text editor, and add a set of following lines: alias key filepath, where alias - is a name for sound, key is set to 0, and filepath is a path to the sound. Then just open INS file in the playing module(piano) and play whatever you want :)

SNC files are used to store melodies you've already played, or obtained from MIDI file with MIDIParser(see below). You can play one SNC file with different instruments, and get different result every time. Or, you can create a CD with songs, performed on your own unique INS file :)
You can read more about SNC format in the documentation(at our site, or with downloaded Instrument Modeller)
Q: What is MIDIParser? Why do I need it?
A: This program allow you to process MIDI files and convert them into SNC files, which you can easily play via Instrument Modeller with your own musical instrument. Pass a MIDI file to MIDIParser, and it will generate 1 or more SNC files, containing tracks from MIDI file.
Q: What is SNCParser? Why do I need it?
A: This program allow you to process SNC files with you instruments and get WAV melodies. Pass an SNC file with an INS file to SNCParser, and it will generate melody, played on that instrument.
Interface questions
Q: When I try to play SNC file using my instrument, I get "Unknown alias 5C" error. What's happened?
A: SNC file you want to play contains notes, that your instrument does not have - imagine, that you are trying to play complicated melody on the piano with 1 octave ;) Most of the time, creating a bigger instrument (with more notes) will solve this problem.
Q: When I try to play SNC file using my instrument, I get "Unknown alias 5C" error. What's happened?
A: SNC file you want to play contains notes, that your instrument does not have - imagine, that you are trying to play complicated melody on the piano with 1 octave ;) Most of the time, creating a bigger instrument (with more notes) will solve this problem.
Q: When I try to generate notes in Digital waveguide and get an error "Incorrect 2d graph for flute". What's happened?
A: In Digital waveguide model every point must have no more than 2 connections. Check if any point has more than 2 connections. Also, one reason possible - is that playing point must be on either side of the graph, otherwise, it will not work.