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... through Patreon:   / moritzklein  
... by buying my DIY kits: https://www.ericasynths.lv/shop/diyk...

Complete project on falstad: https://tinyurl.com/y7eftwyz

In this video, I'll walk you through the process of designing a diode ladder VCF from scratch. Since the topic is rather advanced, I don’t go into great detail about most basic components & what they do. If you are just starting out, I recommend you first watch the rest of my series on filter design. You can find previous episodes here:

Analog Filtering Basics:    • DIY SYNTH VCF Part 1: Analog Filterin...  
Active Filters & Resonance:    • DIY SYNTH VCF Part 2: Active Filters ...  
VactrolBased Voltage Control:    • DIY SYNTH VCF Part 3: Resonant HighP...  

Also, if you need a refresher on how the inverting op ampconfiguration works, I recommend watching my video on a sawtoothtotriangle converter, which you can find here:    • DIY SYNTH Quick Tip: SawtoothtoTria...  

If you want to follow along – which I strongly recommend –, here's a bill of materials:

Semiconductors
11x 1N4148 diode

Capacitors
2x 1uF foil capacitor
5x 1nF foil capacitor

ICs
2x TL074

Resistors
2x 200k resistor
2x 100k resistor
1x 47k resistor
8x 33k resistor
2x 10k resistor
1x 2k7 resistor
2x 2k resistor
1x 1k resistor
1x 330 resistor

Potentiometers
2x 100k linear mono potentiometer

Misc
3x audio jack socket

Chapters
00:00 Intro
01:39 Sound Demo
03:49 Diodes as Resistors?
10:31 Bias Current & Trickery
14:02 MultiPole Diode Ladder
17:23 Driving the Ladder
25:22 Output Stage
27:42 CV Processing
30:53 Resonance
34:45 Final Demo & Outro