Minim
core | ugens | analysis
 

AudioOutput

setTempo

Description

The tempo of an AudioOutput controls how it will interpret the start time and duration arguments of playNote methods. By default the tempo of an AudioOutput is 60 BPM (beats per minute), which means that one beat lasts one second. Setting the tempo to 120 BPM means that one beat lasts half of a second. When the tempo is changed, it will only effect playNote calls made after the change.

Signature

void setTempo(float tempo)

Parameters

tempo — float: the new tempo for the AudioOutput, in BPM (beats per minute)

Returns

None

Related

getTempo ( )

Example

/**
  * This sketch demonstrates how to create synthesized sound with Minim using an <code>AudioOutput</code> and the
  * default instrument built into an <code>AudioOutput</code>. By using the <code>playNote</code> method you can 
  * schedule notes to played at some point in the future, essentially allowing to you create musical scores with 
  * code. Because they are constructed with code, they can be either deterministic or different every time. This
  * sketch creates a deterministic score, meaning it is the same every time you run the sketch. It also demonstrates 
  * a couple different versions of the <code>playNote</code> method.
  * <p>
  * For more complex examples of using <code>playNote</code> check out 
  * algorithmicCompExample and compositionExample in the Synthesis folder.
  * <p>
  * For more information about Minim and additional features, 
  * visit http://code.compartmental.net/minim/
  */

import ddf.minim.*;
import ddf.minim.ugens.*;

Minim minim;
AudioOutput out;

void setup()
{
  size(512, 200, P3D);
  
  minim = new Minim(this);
  
  // use the getLineOut method of the Minim object to get an AudioOutput object
  out = minim.getLineOut();
  
  // set the tempo of the sequencer
  // this makes the first argument of playNote 
  // specify the start time in quarter notes
  // and the duration becomes relative to the length of a quarter note
  // by default the tempo is 60 BPM (beats per minute).
  // at 60 BPM both start time and duration can be interpreted as seconds.
  // to retrieve the current tempo, use getTempo().
  out.setTempo( 80 );
  
  // pause the sequencer so our note play back will be rock solid
  // if you don't do this, then tiny bits of error can occur since 
  // the sequencer is running in parallel with you note queueing.
  out.pauseNotes();
  
  // given start time, duration, and frequency
  out.playNote( 0.0, 0.9, 97.99 );
  out.playNote( 1.0, 0.9, 123.47 );
  
  // given start time, duration, and note name  
  out.playNote( 2.0, 2.9, "C3" );
  out.playNote( 3.0, 1.9, "E3" );
  out.playNote( 4.0, 0.9, "G3" );
    
  // given start time and note name or frequency
  // (duration defaults to 1.0)
  out.playNote( 5.0, "" );
  out.playNote( 6.0, 329.63);
  out.playNote( 7.0, "G4" );
  
  // the note offset is simply added into the start time of 
  // every subsequenct call to playNote. It's expressed in beats.
  // to get the current note offset, use getNoteOffset().
  out.setNoteOffset( 8.1 );
  
  // because only given a note name or frequency
  // starttime defaults to 0.0 and duration defaults to 1.0
  out.playNote( "G5" );
  out.playNote( 987.77 );
  
  // now we can start the sequencer again to hear our sequence
  out.resumeNotes();
}

void draw()
{
  background(0);
  stroke(255);
  
  // draw the waveforms
  for(int i = 0; i < out.bufferSize() - 1; i++)
  {
    line( i, 50 + out.left.get(i)*50, i+1, 50 + out.left.get(i+1)*50 );
    line( i, 150 + out.right.get(i)*50, i+1, 150 + out.right.get(i+1)*50 );
  }
}

Usage

Web & Application