Difference between revisions of "Testing audio output"

From CCRMA Wiki
Jump to: navigation, search
(Reference Signals)
Line 1: Line 1:
 +
== Recording/Analyzing Signals
 +
 +
* Easiest: just write a binary output file.  The [[http://audacity.sourceforge.net/ Audacity]] audio editor can "Import Raw" audio. Select the correct format and import. Audacity is installed on all CCRMA machines or can be downloaded for free [[http://audacity.sourceforge.net/ here]]. You will automatically view the time domain signal. To see the frequency response, you can select a portion of audio and click Analyze->Plot Spectrum.
 +
 
==Reference Signals==
 
==Reference Signals==
  

Revision as of 15:04, 22 September 2010

== Recording/Analyzing Signals

  • Easiest: just write a binary output file. The [Audacity] audio editor can "Import Raw" audio. Select the correct format and import. Audacity is installed on all CCRMA machines or can be downloaded for free [here]. You will automatically view the time domain signal. To see the frequency response, you can select a portion of audio and click Analyze->Plot Spectrum.

Reference Signals

When creating signal generators yourself, you will want to compare your audio output to reference signals. Here are a few audio programing languages/environments that might be useful.

  • [Chuck]-audio programming language (suggested for ease-of-use)
  • [Pure Data]- a graphical audio programming language

SAMPLE CHUCK CODE

   // Comment/uncomment the different oscillators to hear each 
   SinOsc s => dac;
   //TriOsc s => dac;
   //SqrOsc s => dac;
   //PulseOsc s => dac;
  .2 => s.gain;
   while( true )
   {
       440.0 => s.freq;
       100::ms => now;
   }
   // Use this for impulse
   //Impulse i => dac;
   //while( true ) {
   //    1.0 => i.next;
   //    100::ms => now;
   //}
   // Use this for noise 
   //Noise n => dac;
   //.2 => n.gain;
   //while( true )
   //{
   //    100::ms => now;
   //}


Download and install. From there you'll need to create a small bit of code to make the same output signals.