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Implement several different Chowning FM instruments (bell, wood drum, brass, clarinet, and bassoon) and compare them to the sounds of physical instruments. Develop code to model the Chowning algorithms as LabVIEW "virtual musical instruments" (VMIs) to be "played" by a MIDI file within MIDI JamSession.
This module refers to LabVIEW, a software development environment that features a graphical programming language. Please see the LabVIEW QuickStart Guide module for tutorials and documentation that will help you:
•Apply LabVIEW to Audio Signal Processing
•Get started with LabVIEW
•Obtain a fully-functional evaluation edition of LabVIEW


FM synthesis creates rich spectra from only two sinusoidal oscillators, and is able to emulate the sound of many physical musical instruments. John Chowning's seminal publication on audio-range frequency modulation (FM) in 1973 describes a number of different orchestral instruments such as woodwinds, brass, and percussion that can be created merely byadjusting a few basic parameters of the basic FM equation.

In this mini-project, implement several different Chowning FM instruments and compare them to the sounds of physical instruments. Also develop code to model the Chowning algorithms as LabVIEW virtual musical instruments ( VMIs ) to be "played" by a MIDI file within MIDI JamSession .

Prerequisite modules

If you have not done so already, please study the prerequisite modules FM Mathematics and Chowning FM Synthesis Instruments in LabVIEW . If you are relatively new to LabVIEW, consider taking the course LabVIEW Techniques for Audio Signal Processing which provides the foundation you need to complete this mini-project activity, including working with arrays, creating subVIs, playing an array to the soundcard, and saving an array as a .wav sound file.


  • All LabVIEW code that you develop (block diagrams and front panels)
  • All generated sounds in .wav format
  • Any plots or diagrams requested
  • Summary write-up of your results

Part 1: chowning fm instruments

Chowning FM Synthesis Instruments in LabVIEW provides the specifications for a generic FM synthesis instrument, parameters for a number of different instruments, and a screencast video that walks through the complete process to implement the Chowning clarinet in LabVIEW. Refer to the PDF document in that module that contains theparameters for the remaining instruments: bell, wood-drum, brass, and bassoon. Create your own LabVIEW implementation of each of these four instruments (the clarinet VI is available in that module, as well).

Save a representative sound from each of the five Chowning instruments to a .wav file.

Consider using an audio editor such as Audacity to merge the individual .wav files into a single .wav file that you submit as your deliverable. You can also add your own voice annotation to explain your work.

Part 2: comparison with physical instruments

Visit the Musical Instrument Samples database created by the Electronic Music Studios of the University of Iowa at (External Link) . These recordings of actual instruments were made inside an anechoic chamber to eliminate reflections and other artifacts, so the spectra of theinstruments are as accurate as possible. The files are stored in AIFF format; use an audio editor such as Audacity to import the AIFF format. Audacity also includes a tool to view the spectra of the soundfile.

Compare and contrast the FM sounds you created for brass, clarinet, and bassoon to those of the real instruments. Consider time-domain envelope shape and spectrogram patterns.

Part 3: chowning vmis for midi jamsession

In this part, convert each of the five Chowning instruments you implemented in Part 1 into its own virtual musical instrument ( VMI for short) that can be played by "MIDI JamSession." If necessary, visit MIDI JamSession , download the application VI .zip file, and view the screencast video in that module to learn more about the application and how to create your own VMI. Your VMI will accept parameters that specifyfrequency, amplitude, and duration of a single note, and will produce a corresponding array of audio samples.

You may wish to keep all of your existing front-panel controls available so that you can listen to your VMI during development. Adjust the parameters to obtain pleasing and realistic settings, and convert the front-panel controls to constants and remove all indicators. Your finished VMI must not contain any front-panelcontrols or indicators beyond those provided in the prototype instrument.

Finally, choose a suitable MIDI file and use MIDI JamSession to play your FM VMIs. MIDI files that contain multiple channels are ideal, because you can individuallyassign each of your five VMIs to a different instrument.

Create a .wav file of your finished work.

MIDI percussion events are found on Channel 10, a reasonable place to use your wood-drum instrument. Be aware that the "frequency" value produced by the prototype VMI derives directly from the "note number" value of the MIDI "Note On" messages in the file. On Channel 10, the note number selects froma palette of different percussion instruments as defined in the General MIDI Sound Set ( (External Link) ), so interpreting the value as frequency is meaningless. You can either set up your wood-drum to produce the same waveform independent of the frequency parameter, or you can devise a scheme to translate the note number into useful parameter change for your instruments.

Questions & Answers

how environment affect demand and supply of commodity ?
Amos Reply
Wht at the criteria for market ?
what is difference between monitory policy and fiscal policy?
Malik Reply
monetary policy is a policy thrust by National Govt(CBN) to influence government spending, purchase &taxes
necessity of economics
Pamela Reply
I will say want,choice,opportunity cost,scarcity,scale of preference
what is monopoly market.How price output are determined under monopoly market
b) Monopoly market is an impecfect market where s single firm having the innovation to produce a particular commodity.Prices are determined through output since there are no other competitive.
Monopoly market:firm has market power & does not respond to market price
Explain the process of price determination under perfect competition market with suitable diagram
bisham Reply
Price determination under perfect competition via this process :firms have no market power to influence price rather firms respond to market price.
price is different from demand- demand is amount of commodity
Effah Reply
demand is amount /quantity of commodity a potential buyer is willing to buy at a given price at market
demand is a desire of customer on commodity with the ability to pay it and willing to buy it at given price of commodity
demand is price of what
Faith Reply
show that shortrun average cost
Baby Reply
what is economics
Mbah Reply
what is money
what is money
Difine macro economics
money is a medium of exchange between goods and services,maybe inform of currency.
Economics is study of how human beings strive to satisfy numerous wants using limited available resources.
how do you find the maximum number of workers the firms should employ order to produce where there are increasing returns
what are implications of computing national income?.
what is the formulae for calculating national income
it calculated by value added method
classify the production units like agriculture, banking, transport etc
money is anything that is generally acceptetable for human
Estimate the net value added(NVA) at fixed cost by each industrial structure
definition of unemployment
Adam Reply
what are the causes of unemployment?
Mbubi Reply
The main causes of unemployment are listed below. 1. Frictional unemployment 2. Cyclical unemployment 3. Structural unemployment
We can also categorize the causes on a broader sense as: 1. Political and 2. Social cause As unemployeement root causes are embaded in this two.
would opportunity cost exist if there was no scarcity?
yes just because the opportunity cost arose when there is Alternative to choose among the alternatives.
I am thinking that, if our resources were unlimited, then there wouldn't be any need to forgo some wants. Hence the inexistence if opportunity cost
politics has done what?
consider time assani
I'm Emmanuel,...I taught the main cause is the change in gov't.
...Lack of capital to set up a firm respectively
I would like to bring in Educational levels can also be the cause the cause of the problem respectively
lack of skills among the new generation is the serious issue.
Where I come from , I don't see why education or personal aspects seem to do with unimployment, technically the motivation and eigerness in all works of live is there , dispite the cultural influence and physical bearriors;the thing we lacking is Government Support and open market ethics.
sorry about that-(repation). We have a over powering ethical political system that's displacing the marketing asspects of economy and causing large scale unemployment right across the board...
can someone Explain Expansionary Monetary Policy and Contractionary Monetary Policy Using one of the instrument of Monetary Policy? Please am kinda lost here?. ta
Emmanuel Reply
using a graph show the case of substitute and compliment goods
Ade Reply
can anyone give me a simple explanation to Five Sector Macroeconomics?
Can someone please define what economics is
jason Reply
economics simply is a social science subject that study human behavior.
economics is a social science which studies human behaviour as a relationship between ends and scarce means that has alternative uses
Can someone please tell me how to calculate GDP
emmanual kapal to calculate GDP (Gross Domestic Product) has three method in calculating it (1)income approach (2) expenditure approach (3) value added method
thanks Alae
u are welcome
in basic terms economics is revered to as battery system, it date back to when Men sees the need to exchange sapless goods and produce to gain , either wealth , basic necessities or to establish trading ties for personal benefit or social asspects in terms of coexistence and continuity, future .
what is the law of demand
Berlinda Reply
keep other thing constant, when the price increases demand decrease when the price decreases demand increases of the commodity.
all things being equal,quantity demanded decrease as price increase and increase as price decrease
there's practial joke to it ..." the higher the demand ; scarcity, increase in production and drop in quality"... quite the controversy - for example China vs Europe, United States and we are all boxed up in between somewhere...
Other thing remain constant the low price of commodity the high quantity of commodity and vice versa is true
Explain Effective demand
Anita Reply
What is effective demand
like Modi is in demand...best example of effective demand
Don't get you
Anita you mean you don't get me or who?
level of demand that represents a real intention to purchase by people with the means to pay
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