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Cavisynth SEQ-UFD Sequencer


Control Voltages, Please! 

My original idea was to control my synth with Ableton Live and MIDI but it turned out it's more fun to generate control signals with LFO's and other synth modules. The logical next step was of course a sequencer module. The Arduino based Cavisynth SEQ-UFD was the cheapest DIY project I could find and the specs looked good.

Sourcing Headaches and Jumper Wires, Part 2

This module build was pretty much a sequel to my Cavisynth Ardurack build. I had lots of problems with the required part types and ended up using all kinds of ugly hacks. With a small module like Ardurack I could live with that but the SEQ-UFD has so many jacks and pots that I just had to make another order to Cavisynth and get correct components before turning on my soldering iron.

SEQ-UFD consists of 3 PCB:s. It uses the same The Arduino Pro Mini processor module as the Ardurack.

Panel under construction

All PCB's are directly attached to the panel with jacks or pots. This caused issues because I originally used cheap Alps pots without panel fastening nuts. I had to change some of the pots to a different type to attach the PCB to panel.

Lots of wiring required. Luckily not as much as with the Ardurack module.

Two of the PCB's are connected with a flat cable. The third one required jumper wires.

Where's the Major Scale?

It's already a while since I built this module. First I was somewhat disappointed with it because it's difficult to get properly tuned notes out from it. There's no quantisation in the CV outputs so they can be used for experimental sequences but not for generating real melodies tuned up with other note sources. I eventually ended up buying a Korg SQ-1 sequencer which has the possibility to fix notes to minor or major scale. I really like the Korg sequencer and have been using that for my melody generation needs exclusively.

...who cares!

Luckily Cavisynth SEQ-UFD has lots of other features in addition to the basic note-cv generation possibilities. It contains individual gate outputs for every step. This makes it possible to use it as a clock divider or a simple drum sequencer. Lately I have used it a lot to drive all kinds of percussive things. The firmware also contains an alternative clock divider mode but I haven't had time to learn how it works yet.

Of course it's also possible to tweak the firmware. The generous amount of pots and jacks means this module has some serious hacking potential! If only I had more time...
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