Overview

This Audio Unit module provides a custom interface to Apple's DLS Music Device, an Audio Unit that is part of OS X. It is a sample-playback synthesizer that can play DLS and Soundfont sample banks. The default soundbank for this synth is the Quicktime Music Synthesizer, a General MIDI soundbank You can also load other soundbanks, and using 3rd-party tools such as Polyphontics, you can create your own as well.

This synthesizer has 16 parts, each of which responds to one of the 16 MIDI channels. In addition to picking an instrument for each part, you can set volume, quality, tuning, and maximum cpu load for the synth overall.

The 10th part (on MIDI Channel 10) is set by default to the 'Standard' instrument, which is a General MIDI drum-kit. The drum-kit instruments are located near the bottom of the (rather large) instrument menu. It is customary for General MIDI devices to use channel 10 for drum parts, but you are not restricted to this.

Techniques

Although the DLS Synth is a very basic sample playback synthesizer, it takes up very little CPU load, and can be used to make very interesting music by using it unconventional ways. Here are some suggested techniques to use:

• Layer a second or third part offset by a few semitones to thicken a sound. Use 5ths (7 semitones) and octaves (12 and 24 semitones) for a stronger sound, use closer ratios such as minor 3rds (3 semitones) and 4ths (5 semitones) for a thicker sound.
  
  
• Layer a second or third part that uses a different instrument. This is a common trick in hardware synths. Layer a percussive sound with a pad, or layer some related synth-type sounds to get a richer tone.
  
  
• Program sequences that use extreme pitch ranges. Most of the sounds in the Quicktime GM bank are not multi-sampled over a large range, and can become very interesting when pitched very high or very low.
  
  
• Program sounds with very short gates, to turn sounds with strong attacks into percussive sounds. Program a complex rhythmic pattern, add delay and reverb, instant minimalist film music.
  
  
• Modulate the tuning parameter using a sequencer or DualLFO module (via the ParamMod module) to get a variety of pitch effects, from detuning, to wild pitch-sweep soundscapes. Add delay and reverb to enhance this effect.
  
  
• Use lots of effects. Distortion, delays, reverb, etc. Effects are very good at making otherwise bland sounds interesting, or to get disparate sounds to sit well in a mix.
  
  
• Pipe in MIDI CC to control per-part volume (CC 7), modulation (CC 1) or pan (CC 10). Panning is especially effective for animating sounds. Pitch bend (use the Bender module) is also useful, even though the bend range implemented by this synth is only +/- 2 semitones.
  
  
• Use a very bright sounding instrument, then follow it with the Apple Lowpass filter. Doesn't sound as good as a real analog synth, but is still a very useful trick.
  
  
• Add new soundbanks, or create your own.

Parameters

This is controlled via the small 'power' button on the module header. It is present on every Numerology module, but is especially important for AudioUnits. Since audio synthesis and processing can be very CPU intensive, it can be very useful to turn things off when they are not needed. This is what bypass does: it skips evaluation of the AudioUnit. In the case of AU effects, audio passes through unchanged. And since the bypass setting can be on or off for any preset, you can use it to turn AU's on and off for each stack preset.

Ports

This allows you to send MIDI to your AU, very handy for triggering notes in AU synths.

This is the audio output port for the module.