The following reference and resources are intended to help students, budding designers, engineers and audio ethusiasts bring their creations to life.  The topics represent reoccurring themes, challenges or common asks seen over the course of many years in the industry.  We hope that should you find yourself confronted with such tasks, we are able to get you pointed in the right directions so that you can keep focus where it belongs... On the audio!

 

Audio Programing Tutorials

 

Quick VST Development with JUCE - Original Redwood Audio tutorial on a free tool-chain (including Graphical User Interface "GUI") for VST plugin developement using the JUCE library.

 

 

Audio Coders FAQ

 

 

Why does audio drop-out and/or my CPU spike when running my audio plugin or application?

 

Answer: You are likely seeing the effect of denormal float math on your processor - try attaching the kill denormal process to the output of any DSP elements with feedback (e.g. IIR filters, reverb, allpass structures, etc.)  If that fixes it, you can look for a more elegant platform-specific solution with that root-cause in mind.

 

 

Collected Web References

Audio Engineering Society E-Library - central group of publications on current thinking in audio, typically easier to read than IEEE, but not always enough info to clearly implement.

 

DAFX - Generally free, online procedings from the Digital Audio Effects (DAFX) conferences.  Often great ideas are published here with very practical insights on understanding or implementing audio algorithms  

 

Julius O. Smith - Serious collection of online publications from an imprortant professor out of Stanford's Center for Computer Research in Music and Acoustics (CCRMA)      

 

Music DSP Source Code Archive - Code archive, additional reference links, and one of the best forums around for audio FX development

 

Some specific callouts (these come up a lot!):

Audio EQ Filter Cookbook - by an excellent engineer and contributer to musicdsp.org, Robert Bristow-Johnson.  While making your library, consider: Smooth and Safe Parameter Interpolation of Biquadratic Filters in Audio Applications, by Victor Kalinichenko (though note the print has an error in one of the equations)

 

Denormal Numbers in Floating Point Signal Processing Applications - by Laurent de Soras.  kill_denormal_by_quantization may be just what your reverb or IIR needs to run smoothly.

 

Digital Audio Resampling - by J.O. Smith, everything you need to get high quality resampling into your applications (including some source).

 

 

Recommended Forums/List Servers

Mailing Lists:

    ASIO: Subscribe at Steinberg Developer Portal download page for ASIO SDK.

    VST Plug-ins: Subscribe at Steinberg Developer Portal download page for VST Plug-In SDK.

    Auditory Perception: Auditory mailing list (hearing, perception and cognition of sound/audio)

    Music DSP: music-dsp mailing list (audio algorithms and effects)

    OpenAL: OpenAL mailing list (OpenAL, EFX and other extensions)

    Surround Sound: Sursound mailing list (Surround Sound, Ambisonics, WFS etc.)

 

Audio Forums:

    KVR:  http://www.kvraudio.com/forum/

          "Forum 33"  DSP and Plug-in Developement

   HydrogenAudio: Audio Technology Enthusiast's (Audio Codecs, listening tests, etc.)

 

Recommended Reading

Applications of Digital Signal Processing to Audio and Acoustics, edited by Mark Kahrs and Karlheinz Brandenburg, ISBN: 0-7923-8130-3, Springer, 1998

 

DAFX -  Digital Audio Effects, edited by Udo Zölzer, ISBN: 978-0-470-66599-2, John Wiley & Sons, 2011