This module is how we control volume in our modular system, and it works by multiplying different signals together (see video below). There are two complete voltage controlled amplifiers here, and an output that can mix (sum) them together. The jacks at the bottom of the module are the audio inputs, the jacks at the top are the audio outputs, and the topmost knobs act like you would expect a volume knob to (clockwise turns the volume up, counterclockwise turns it down).

What makes a voltage controlled amplifier special is what’s going on in the middle of the module. This is where we input control signals that can turn the volume up and down in ways that our fingers couldn’t do. The switches change how the module responds to a control voltage, and the knob above those inputs changes how much of an effect the control has.

Inspired by the MFOS dual VCA, built around an LM13700 OTA and featuring cv input attenuverter and output sum. Can be used as two separate VCAs or a voltage controlled mixer with switch between exponential and linear cv response.

See amplitude.

Low Frequency Oscillator with sine, saw, ramp, triangle, and square wave outputs. Switch between three frequency ranges and adjust with freq knob. LED flashes to indicate rate of square wave high and low. Frequency ranges from low audio to cycles lasting more than a minute. [For more information about how this module is used and fits into a modular system, check out the pages about amplitude and frequency].

Attack Decay Sustain Release (ADSR) are the 4 phases of this control voltage generator. Together they make variations of that mountainous shape that is cutting across the sliders. Why that shape? Well, it turns out that we can mimic a lot of different musical instruments by adjusting the length of each section, and applying the resulting voltage to the cv input of a voltage controlled amplifier or voltage controlled filter.

For instance, if we want to create a percussive sound we could apply the envelope to a VCA and make the attack (that first stage sloping up) very short, the decay (the second stage sloping down) a little longer, and the sustain and release unnoticeably short. To create a plucked string sound we could lengthen the sustain and release. For a bowed string we could lengthen the attack, and so on.

More information to come…

Dual four pole filter. High pass and low pass. More info to come.

Aenean luctus quis ante id volutpat. Quisque sed elementum mi, nec porttitor dui. Donec sollicitudin finibus diam auctor sagittis. Nullam lacinia mollis urna, nec porta nibh. Vivamus ac faucibus nulla. Nulla facilisi. Fusce tincidunt ipsum aliquet, lacinia augue vitae, bibendum lectus. Suspendisse egestas sapien libero, eu efficitur lorem consectetur.

Aliquam hendrerit risus in metus luctus, id posuere turpis dapibus. Nunc magna elit, vehicula at odio et, sodales semper ante. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Integer tempor urna ut nisl eleifend mattis. Aliquam quis egestas eros. Ut ac leo id ipsum vulputate fermentum eget eu nibh. Fusce efficitur cursus iaculis. Aenean tristique egestas ex, at dignissim sapien pellentesque eget. Nullam placerat, urna et consequat tempor, velit leo porttitor urna, vitae vulputate arcu massa eu erat.

Maecenas et augue eget lorem hendrerit dictum eget a magna. Praesent venenatis finibus luctus. Fusce hendrerit neque ultricies dolor porta fringilla. Maecenas non nisl placerat, pharetra quam ut, sodales eros. Duis ultricies in quam non elementum. Aliquam faucibus, augue a blandit laoreet, sem velit scelerisque odio, a viverra dolor erat vel mauris. Nunc eget ligula at velit feugiat accumsan in nec quam. Cras elit ante, convallis eu mattis sit amet, malesuada eu tellus. Vivamus elit dui, rhoncus ac velit id, vestibulum facilisis purus. Aliquam imperdiet ultricies pellentesque. Morbi at odio eu sapien venenatis congue.

Vivamus sit amet sapien vel neque convallis convallis. Fusce malesuada quis orci eget volutpat. Vestibulum pellentesque egestas orci id maximus. Vivamus felis sem, sagittis ut sollicitudin vitae, porttitor vitae arcu. Maecenas ut nulla vel leo hendrerit congue quis at turpis. Aliquam quis elementum nisi, sed lobortis dui. Maecenas dictum sagittis nibh, id placerat velit maximus ut.

Nullam quis massa sit amet justo tincidunt varius. Etiam in enim vitae neque dapibus condimentum vitae nec est. Sed et sollicitudin nisi, eget dictum massa. Vestibulum cursus, mauris a convallis semper, turpis dui rutrum augue, sed vestibulum felis augue vel orci. Suspendisse sed porta neque, eget fringilla lacus.

Donec commodo aliquam quam id dignissim. Sed id ipsum eget quam malesuada gravida. Integer laoreet eget velit in posuere. Ut euismod neque vitae nunc gravida, sit amet pharetra nunc luctus.