Digitally Controlled Expression - Get Expressive!

Stefan Fast of YouTube channel ThePedalZone goes on a trip to the creative playground that is expression. Modern technology is taking it to the next level…

- Stefan Fast

The joy of manipulating your tone hands-free in real-time was once reserved for treadle-based effects such as the wah and Whammy, or expensive rack-based effects. The world of pedals has come such a long way over the recent years, however, that it’s more or less become the norm – rather than the rare unicorn-like exception it once was – for a pedal to have some sort of expressive capabilities either via ‘expression control’ or ‘control voltage’. So, let’s take a look at some of the different expression devices out there and how I like to use them. But first, I’ll quickly break down the differences between Expression and Control Voltage…

1. EXPRESSION VS CONTROL VOLTAGE

You’ve probably encountered expression control before, but maybe the world of the control voltage (aka CV) is new to you. Both are methods that allow you to control parameters on your pedals, but where all pedals with expressive capabilities can handle expression, not all can handle CV. The easiest way to clarify the difference between the two is to see the expression as a passive control method and CV as an active control method.

A device such as an expression pedal receives a reference voltage from the effect pedal it’s connected to, and then divides that voltage through the use of a resistor, which is the potentiometer inside the expression pedal. CV, on the other hand, actually sends alternating current directly to the pedal in order to control it. This means that if you’re using CV with a pedal that’s not designed to take this voltage, you can potentially fry it. So be careful out there! It’s a wild sonic world.