Modular synthesis on the web

The modular synthesizer is a type of synthesizer consisting of separate specialized modules. The modules are typically connected together with patch cords in different ways as needed to generate needed tones. Typical modules are oscillators (operate on frequency), filters (spectrum), amplifiers/gates (amplitude) and Envelope generators (dynamic control). The earliest commercial modular synthesizers were developed, in parallel, by R.A. Moog Co., and Buchla in 1963Hardware offerings range from complete systems in cases to kits for hobbyist DIY constructors. For more information read the introduction by Roland and How to build a modular synth.

Today modular synthesizers exists in both physical and virtual forms. Modular Music Synthesis On The Web article introduced me to an interesting web based instrument: Zupiter is a modular synthesizer that runs in your browser. Zupiter app is written entirely in JavaScript and makes use of both the web audio and web MIDI APIs. You can play notes using your computer keyboard (A to L keys), using a built in sequencer node, or you can connect an external MIDI keyboard or sequencer. You can make your own synth by combining building blocs graphically together or you can play with the provided examples. Besides synth parts there is an oscilloscope module that can show you waveform in real time.


Here is a video that introduces you to Zupiter:

After interesting introduction you can go directly to to start playing and experimenting.

Some interesting synth examples with Zupiter:

Interesting synth to play with and my adaptation of it

Acid synth at

Several sequencers in one project

DTMF synth


Here is a link to my earlier posting on other type of web based synths that you might also find interesting to look at.


  1. vex 3 says:

    The modular synthesizer you share is great. with many great features. Hopefully you will have more great posts.

  2. Tomi Engdahl says:

    Designed for easy re-programmability via CircuitPython, this 8HP Eurorack module is a flexible piece of open source hardware.

    Thea Flowers’ Winterbloom Sol Module Offers Eurorack Compatibility and CircuitPython Programmability

    Designed for easy re-programmability via CircuitPython, the 8HP Eurorack module is a flexible piece of open source hardware.

  3. Tomi Engdahl says:

    The KiloDrone Features a Thousand Individual Oscillators
    Sam Battle, of the LOOK MUM NO COMPUTER YouTube channel, built a synthesizer with 1,000 individual oscillators.

  4. Tomi Engdahl says:

    This Audio Mixer Is A Eurorack

    Music making and DJing have both become arts predominantly pursued in a computer, as the mighty USB interface has subsumed audio, MIDI, and even DJ turntable interface controllers. There was a time though when an indispensable part of any aspiring performer’s equipment would have been an analog mixer, a device for buffering and combining multiple analog audio signals into a single whole. A mixer is still a useful device though, and [Sam Kent] has produced a very nice one that takes the form of a set of Eurorack modules made from PCB material. There are two types of modules, the main channel module which you can think of as the master module, and a series of isolator modules that handle the individual inputs.

  5. Tomi Engdahl says:

    I built an analog synthesizer from scratch. Here is how I did it…

  6. Tomi Engdahl says:

    The power of a simple sequencer for eurorack – with the Korg SQ-1

    Today we are going over some reasons why a simple sequencer like the Korg SQ-1 will add a lot of value to a eurorack or modular system. We start with a quick overview of the Korg SQ-1, and then we move on with a series of patch-tips, divided in a few sections. We go over melodic sequencing, CV sequencing, and trigger sequencing.

    00:00 – Intro
    00:43 – Korg SQ-1 overview
    03:08 – Melodic sequencer
    06:30 – CV sequencer
    08:39 – Trigger sequencer
    11:33 – Clock

  7. Tomi Engdahl says:

    The Most Beautiful Synth Of ALL TIME???

    Both #andrewhuang and I recently received delivery of some large scale synths. Andrew beat me to the chase claiming his synth was the most beautiful in the world. In this film I challenge that notion with an absolutely colossal beast by #analoguesolutions . Indeed it is actually called “The Colussus” by Analogue Solutions. I put it immediately to work making a free sample the “12 oscillator doom drone” for you to put in your own music. But I also possibly uncover the most beautiful synth that neither of us own nor will ever?

    00:00 Intro
    00:52 Whats It All About
    01:58 Setting Up A Patch
    07:45 So How Does It Sound?
    08:27 Why Did I Make This Investment?
    09:13 Making The “DOOM DRONE”
    10:07 Playing The Free Doom Drone Sample Pack
    10:47 The ACTUAL Most Beautiful Synth Of All Time

  8. Tomi Engdahl says:

    Getting started with modular synths – Step 1: Building a DIY Eurorack case

  9. Tomi Engdahl says:

    The analog oscillator core anyone can build | DIY VCO Part 1

    In this series, I’m taking a detailed look at how to build an analog VCO from scratch, using just a handful of cheap components. It’s the basis for any synthesizer. To keep it as beginner-friendly as possible, I’m explaining what all the components do in detail.

    This first part deals with the oscillator core, op amp-buffers, AC coupling and voltage dividers. If you want to follow along, here’s a bill of materials:

    1x Breadboard
    2x 9V battery plus clip OR 1x dual 9-15V power supply
    1x 40106 IC
    1x TL074 IC (you can also use a TL072, we won’t be needing more than one op amp)
    1x 1N4148 diode
    1x 1 uF foil capacitor
    1x 2.2 nF foil capacitor
    4x 100k resistor
    1x 3.5mm OR 6.35mm jack socket
    lots of jumper wires

    00:00 Intro & Sound Demo
    01:18 Electricity & Oscillation Basics
    12:13 Materials Overview & Build
    16:20 Buffers & Negative Voltage
    19:37 Offsets & AC Coupling
    23:45 Voltage Dividers
    26:39 Listening & Outro

  10. Tomi Engdahl says:

    How to get Started with Modular Synths – Behringer Bundles & First Patches

  11. Tomi Engdahl says:

    Virtual Eurorack Based CPU Computes To The Beat Of A Different Drum Module

    In Arthur C. Clarke’s 1972 story “Dial F for Frankenstein”, the worlds first global network of phone exchanges was created by satellite link, and events happened that caused the characters in the story to wonder if the interconnected mesh of machinery had somehow become sentient. And that’s what we wondered when we saw this latest virtual CPU construction built by GitHub user [katef] and made from a virtual analog synthesizer software called VCV Rack.

  12. Tomi Engdahl says:

    Choosing A 500-series Chassis

    Not all 500‑series racks are created equal. Here’s what you need to know to make your choice.

  13. Tomi Engdahl says:

    A 70′s Synth You Made At Home With Monthly Magazines

    Time To Look At The Elektor Formant

  14. Tomi Engdahl says:
    Did you know that in the late ‘70s, the Elector Formant modular synthesizer, a DIY concept was launched, which during the time became quite popular. It was designed by C. Chapman.
    The Formant was published in a series of articles in Elektor (in The Netherlands, Elektuur), and later as a book with a compilation of the articles.
    A year later there was another book with additions and extensions by M. Aigner, an Austrian.

  15. Tomi Engdahl says:

    Rave in a briefcase
    Trifted briefcase, dumpster dived rails, electronics out of an old skiff, panel lasercutted out of a broken frame

  16. Tomi Engdahl says:

    Synth/Electronic in Eurovision Song Contest

    Here are all the synthesizer and electronic music entries that have competed in Eurovision Song Contest.

  17. Tomi Engdahl says:

    Are you ‘tone deaf’? Watch this video to find out! (Part 1)

  18. Tomi Engdahl says:

    Orbital’s Paul Hartnoll shows us how he keeps the classic sound of rave alive

    Earlier this year rave pioneers Orbital – the British electronic duo made up of brothers Phil and Paul Hartnoll – returned with their first studio album in six years, Monsters Exist.

    Whilst preparing for a string of live dates in the US and UK, Paul took the time to show us how he keeps the classic sound of rave alive with a combination of state-of-the-art samplers, classic synths and vintage gear.

  19. Tomi Engdahl says:

    Building a DIY Minimoog

    0:00 Intro
    1:38 Oscillator Trade-Off
    2:35 Ordering Parts
    3:54 Component Matching
    5:57 Board Assembly
    7:14 Enclosure
    8:16 Mounting & Wiring
    10:54 First Test
    12:07 Fixing Bugs
    13:10 MIDI Controller
    15:04 Tuning
    15:37 Final Demonstration
    18:22 Outro

  20. Tomi Engdahl says:

    A DIY Synthesizer You Built From A Magazine – The Digisound 80

  21. Tomi Engdahl says:

    Playing Shows With DIY Synthesizers goes wrong, a lot.


  22. Tomi Engdahl says:

    Turning an Old Toy into an Eurorack Drum Module

  23. Tomi Engdahl says:

    Minimoog Fight: Behringer vs UAD vs Softube vs Arturia vs GForce

    Who’s the cheap minimoog champion?
    A shootout between the Behringer Model D, the UAD Moog Minimoog, the Softube Model 72, the Arturia Mini V3 and the GForce Minimonsta2. FIGHT!

    0:00 Intro
    0:30 Stage 1 – Funk Bass
    1:50 Stage 2 – Detuned Saw
    2:51 Stage 3 – Overdrive
    4:14 Stage 4 – Filter Sweep
    4:49 Stage 5 – FM
    5:54 Conclusions

  24. Tomi Engdahl says:

    Korg Berlin shows off a prototype ‘acoustic synthesizer’
    The Acoustic Synthesis_phase5 is the first instrument from Korg’s experimental R&D group.

  25. Tomi Engdahl says:

    Olegtron 4060 MKII -signaaligeneraattori

    Vallankumouksellinen pöristin
    Kompakti muotoilu
    Made in Turku!

    Olegtron 4060 on pieni mutta pippurinen signaali- ja sekvenssigeneraattori, joka on juuri niin monipuolinen kuin tahdot!

    Olegtron 4060:n kytkentä perustuu CD4060-CMOS-piiriin, joka koostuu oskillaattorista ja kymmenen matalampaa oktaavia tuottavasta jakajasta. Piiri tuottaa siis useita eri taajuisia signaaleja, melodisista sävelistä rytmisiin naksahteluihin. Halutut signaalit yhdistetään komponenteilla tai jumpperijohdoilla laitteen 3,5mm stereoliittimeen, joka voidaan yhdistää esim. vahvistimeen, analogisyntetisaattoriin tai videomonitoriin. Liittämällä komponentteja laitteen käyttöliittymään, eri signaalien välille, niiden aiheuttama kuormitus saa laitteen tuottamat taajuudet ja signaalien voimakkuuden huojahtelemaan. Oskillaattorin kantataajuutta ja huojahtelun voimakkuutta säädetään kahdella potentiometrillä, FREQ ja STARVE. Kytkennät tehdään laitteen 4×40-pinnisen header-liittimen avulla.

    Laitteen mukana toimitetaan monipuolinen komponenttilajitelma: vastuksia, kondensaattoreita, diodeja, transistoreja, valovastus, LEDejä sekä jumpperijohtoja. Kokeilun helpottamiseksi pienet kondensaattori ja vastukset on maalattu toiselta puolelta värikoodein.

  26. Tomi Engdahl says:

    Olegtron 4060 MK2

    Olegtron 4060 mk 2 Introduction – Part III, Sounds & Functions

  27. Tomi Engdahl says:

    Oli Freke presents a synthesizer timeline


Leave a Comment

Your email address will not be published. Required fields are marked *