CV Toolkit - Main Interface.png

CV Toolkit - Standalone Version

Current Version: 1.3 – Download the Manual – Changelog

Price: $19,99

What is CV Toolkit?

CV Toolkit is a standalone application that can be used to control analog synthesizers by sending CV signals through any DC-coupled audio interface or Expert Sleeper's ES-3, ES-4, ES-40, ESX-4CV, and ESX-8CV modules*.
The 1.3 version ships with 24 virtual modules that offer different modulation options such as LFO, shift register, sequencer, envelope generators, etc. CV Toolkit also has a MIDI to CV virtual module that let's you calibrate your VCOs and play them in tune.
You can also use the Routing Matrix to route the output of any of any module to analog outputs, analyzers (LED / Oscilloscope) or even to the input of certain modules (S&H / Biased Switcher / Slew).

Main Features

  • Standalone application – doesn't require any additional software.
  • Virtual Slot System – Change the modules inside the slots and customize CV Toolkit to your own needs.
  • MIDI to CV – Calibrate your VCOs and play them in tune.
  • Hands-on Experience – control all parameters from you iPad using the Lemur app (native OSC integration).
  • Routing Matrix
  • Save and recall patches
  • CV Quantizer – Quantize the output signal of any of the virtual module to a specific key and scale.
  • ScanGraph – a new concept of modulation.
  • MIDI Clock – sync it to your favorite DAWs, drum machines, iOS apps and etc.
  • Eight analog outputs – you can use up to eight analog outputs to send signals to your modular synthesizer
  • MIDI In / Out
  • Works on both Mac and PC
  • 64-bit application
  • Clean and simple interface



Virtual Modules Available

• LFO 1
• LFO 2
• S&H
• Shift Register
• AD 1
• AD 2
• Mix
• Slew
• Delay
• Shaper
• Biased Switcher
• CV Recorder

• Comparator
• MIDI to CV
• Scangraph
• Morphing VCO
• PWM Clock
• Envelope
• Clock Generator
• Euclidean Sequencer
• Step Sequencer
• Oscilloscope
• CV Quantizer
• Offset Generator

Lemur Integration

The hands-on experience provided by modular synthesizers inspire and promote experimentation so that's why CV Toolkit – Standalone Version ships with a full and native Lemur integration.

After setting it up (takes less than 2 minutes), you can put your iPad next to your modular synth, fire up the Lemur app and play around with CV Toolkit without having to reach for your mouse or keyboard.

The Lemur integration is based on OpenSoundControl aka OSC which means that, unlike MIDI, you can control every parameter with full resolution without having to manually map them.

Virtual Slot System

The 1.2 update for CV Toolkit - Standalone Version introduced the new Virtual Slot System (V.S.S) which let's you change the modules inside the slots and customize CV Toolkit to your own needs!

The idea behind VSS is to make the user interface work like a real modular synth case: although the size of the case is fixed, you can swap the modules inside the slots at any time and configure it to best suite your need. Now you can, for example, swap the Envelope module for a Clock Generator. 

Our plan is to keep adding new modules in future updates. If you'd to suggest ideas for new modules, feel free to submit them to us via this form

Why Standalone?

Although the Standalone version cannot be loaded straight into your favorite DAW like a plug-in, there are advantages of having it as a separate app:

  • Easy to setup – multi-channel plugins can take a lot of time to setup
  • Preset Banks – you can store up to 24 presets in a bank and recall them whenever you need
  • Works with any DAW – you can use and sync CV Toolkit with any DAW that can send MIDI Clock
  • Or even without one – if you just want to jam for a while, you don't need to open up your DAW in order to run CV Toolkit

User Videos


MaxforLive Devices

The basic and Pro versions of the CV Toolkit MaxforLive devices are still available.
The basic version can be downloaded from and the Pro version is part of our Spektro CV Devices bundle. 

* Support for the Expert Sleepers ES-4, ES-40, ESX-4CV and ESX-8CV modules is still experimental therefore it might be subjected to bugs. Our plan is to improve the support for these modules in future updates.