In this series, we build a simple LFO module for Eurorack. In the previous step, we designed a dual LED indicator circuit. This will show us the polarity and relative position of the triangle wave. Let’s put it on the breadboard to see if it actually works.
In this series, we design and build an LFO module for our Eurorack modular synth. No module is really complete without blinkenlights. In this part, we design the LFO indicator light with a red/green dual LED, choose the current limiting resistor and smooth out the fading with an op-amp.
The classic Serge Triple Waveshaper (TWS+) by Random Source is a very easy synth DIY build. With the addition of just a couple of jack, pots, capacitors, and a header I had it up and running in no time. A gorgeous sound sculpting addition to my Eurorack modular synth.
The operational amplifier is one of the most versatile and useful components in electronics. The op-amp can be used as an amplifier, attenuator, filter, mixer, comparator, integrator, oscillator, rectifier, peak detector, clipper, and more. So op amps are great building blocks for synth DIY.
Almost no modular synth patch can go without the use of a low-frequency oscillator (LFO). So I decided to build one myself to get my hands dirty on building modules for my Eurorack system. It is based on a fairly simple relaxation oscillator circuit.