The oscillator(s) - what it is and how it is working behind the scenes…
With exception to noise every synthesizer needs some swinging circuit - better known as an oscillator. There are pleanty of circuits doing that thing but we want to look first into Low-frequency oscillator, better known as LFO…
A simple (LF)O
Think of this circuit as a high-speed game of electronic tag between two sections of the op-amp. It’s a self-sustaining loop where each part is constantly reacting to the other to keep the signal moving.
Simulation of a reversed engineered LFO
May 24, 2025Hello folks,
today I want to continue the series about simulation of synth modules with LTspice.
We start with this module from etsy which we disect and reverse engineer, so that we can build it with reverse polarity protection diodes…
We want to analyze this module.
Lets start with the pcbs:
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To begin with, we first want to reversse enginnering the two sides of the pcb, to build another pcb, with reverse polarity protection diodes in the mind, following the schematic in LTSpice: Also here is the download link for the LTSpice file:
Simulation of NLC sloth with LTSpice
May 2, 2025Hello folks,
today I want to continue the series about simulation of synth modules with LTspice.
We want to analyze the sloth module from NLC.
Lets start with the schematic:
Right below is a copy of the schematic, created in ltspice, however missing the potentiometer(s).
Whats important here to note here is that for the fourth op-amp we needed to add some voltage offset of 1 µV to get it working. Additionally to that we need to simulation the power-on cycle of the power supply, by adding the Voltage with PieceWiseLinear function given ze values (t0,v0, t1, t2 ) with the Values 1ms 0V 100ms 12V ..
Simulation of simple LFO with LTSpice
May 1, 2025Hello folks,
today I want to discuss with you the simple LFO made by David Haillant.
It was the very first module I began my dives into the world of diy.
Quite simple and not to complicated to begin with…
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If you do not shy away from mathematical deep-dive explanations - (I sometimes do), you can view the details here (integrator) and here (schmitt-trigger)
A more electronics dive in can be made here (german)
Simulation of modules with LTSpice
April 30, 2025Hello folks,
today I want to start with a topic that I had already longer in my mind and finally took hands on.
We want to simulate a simple LFO (or a normal oscillator, depending on the chosen dimensions) and for that we use the relative well-known tool LTSpice that thankfully also works on Linux machines thanks to using the non-emulator wine.
A simple tutorial how to start that is found here.
Simple, after installation in the shell we enter (or copy):