By Sailormouth
[youtube]http://www.youtube.com/watch?v=di4lLLbQfu4[/youtube]
I have been getting questions about what my pseudo random or fuzzy microcontroller sequencer does, and how it does it. You may remember about 6 months I talked about several kinds of sequencers including the microcontroller sequencer. The concept behind this sequencer is to let it do the work of composing and triggering whatever toys are connected to it. This allows focusing on tweaking the modifications on the toys, and to use a mixer to layer or enhance sounds. The toys have to be prepped with rca jacks to be connected to the sequencer. After this is done the sequencer acts as remote buttons for the toys. The microcontroller is programmed to trigger the buttons in randomly generated patterns. When powered on or reset the code randomly, as random as small digital can be hence pseudo and fuzzy, creates an array of numbers that correspond to the four channels of the sequencer. Then an increment or step size is randomly selected as well as a number of times to repeat moving through the array using that increment size. For example an array of 32 elements might looked like this:
1, 1, 4, 3, 1, 3, 2, 4, 2, 4, 1, 4, 4, 4, 3, 1, 1, 2, 3, 1, 2, 3, 1, 4, 4, 4, 2, 3, 2, 3, 1, 1

If the increment size was 4 and it would repeat this 3 times the pattern would look like this:
1, 1, 2, 4, 1, 2, 4, 2, <repeat> 1, 1, 2, 4, 1, 2, 4, 2, <repeat> 1, 1, 2, 4, 1, 2, 4, 2

If the next randomly selected numbers were 2 and 2 the pattern would be:
1, 4, 1, 2, 2, 1, 4, 3, 1, 3, 2, 1, 4, 2, 2, 1, <repeat> 1, 4, 1, 2, 2, 1, 4, 3, 1, 3, 2, 1, 4, 2, 2, 1

This continues to repeat selecting increment and times to loop until the sequencer is stopped. There is no pause or lag between repeats or moving to the next pattern. Up to four different toys can be triggered per channel, and a mixer allows for complimentary or opposing sounds to be synced. Grouping different sounds for each channel is flexible with the rca jacks. At any point sounds can be swapped from one channel to another. The tempo control combined with the duration of sounds triggered can change the over feel of tracks. An ambient sound scape of low end lower pitch growls can easily become an aggressive torrent of unusual unexpected beats.

Depending on the extent of modifications to the individual toys, or not, effects pedals can always be used as well to add something more. In the possibility of having an odd, irregular, or just bad pattern the mixer can be used to try to downplay this. Another option is to use the “soft kill” switch that will complete the pattern of the current loop regardless of how many more times it would otherwise have left to repeat. Then simply press a button to build a new array and begin playing patterns. On the other hand if a good pattern is going a different switch can latch the loop until the switch is thrown back again no matter how many loop repeats were remaining. There are two LEDs to roughly indicate how many times a pattern is going to repeat so that there is an opportunity to latch the loop. All the patterns in a track are a loose free form that is not remembered or reproducible by the sequencer.

drum & dj track one
drum & dj track two

[youtube]http://www.youtube.com/watch?v=KnNhNyXzyM0[/youtube]
[youtube]http://www.youtube.com/watch?v=2L3yGsiyuWE[/youtube]

As well as toys being controlled by the sequencer I have made a light box circuit to sync a light show to the sounds. This is not a color organ that responds to frequency or intensity of the actual sounds. It acts like the sounds triggered. When a sequencer channel is active one of four channels in the light box turns on any/all lights connected to that channel. Each light box channel can handle up to 2 amps at 115 volts AC. 40 watt bulbs are plenty bright enough so 5 light fixtures per channel can be used, 20 lights in all. If multiple lights are used they can be placed mixed together or in groups.

[youtube]http://www.youtube.com/watch?v=BEWFdqtviP0[/youtube]