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In this project you will design sounds in LabVIEW. You will create two subVIs: one to implement an ADSR-style envelope generator and the other to create a multi-voice sound source. You will then create a top-level application VI to render a simple musical composition as an audio file.
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

Objective

This project will give you the opportunity to begin designing sounds in LabVIEW. You will create two subVIs: one to implement an ADSR-style envelope generator and the other to create a multi-voice sound source. You will then create a top-level application VI to render a simple musical composition as an audio file.

Prerequisite modules

If you have not done so already, please study the prerequisite module Analog Synthesis Modules . 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.

Deliverables

  • 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: adsr envelope

Create the subVI ADSR.vi to generate the ADSR-style envelope specified in ; recall that ADSR stands for "Attack Decay Sustain Release."

Specifications for the ADSR-style envelope

The envelope shape is defined over a normalized time interval of 0 to 1; the envelope stretches or compresses to match the actual duration requested. The three time intervals are likewise expressed in normalized units, so an attack duration (tA) of 0.2 indicates that the attack time is 20% of the entire envelope duration. The envelope values range from 0 dB (full sound intensity) to -40 dB (close to silence). Once you have defined the envelope shape in terms of straight-line segments, you can create the envelope amplitude waveform by undoing the decibels operation; recall that an amplitude "A" expressed in dB is 20 log10(A).

The subVI requires the following controls as input parameters (units specified in brackets):

  • duration [s] - total duration of envelope
  • fs [Hz] - system-wide sampling frequency
  • t values - three-value array containing attack (A) interval, decay (D) interval, and release (R) interval. All three values are in the range 0 to 1, so the intervals are to be treated as fractions of the total duration of the envelope. For example, A=0.3 indicates the attack interval is 30% of the envelope's duration.
  • e values - two-value array containing the envelope value at the beginning of the sustain interval (eS in the diagram above) and the envelope value at the beginning of the release interval (eR).

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
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Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
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it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
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On having this app for quite a bit time, Haven't realised there's a chat room in it.
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Source:  OpenStax, Musical signal processing with labview (all modules). OpenStax CNX. Jan 05, 2010 Download for free at http://cnx.org/content/col10507/1.3
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