CV Tools: Overview & Technical FAQ
What is CV?
CV is an abbreviation of "Control Voltage"; an analog method of controlling synthesizers, drum machines and other similar equipment.
What is CV Tools?
CV Tools is a free pack consisting of CV-enabled instruments, synchronization tools, and modulation utilities that enable users to seamlessly integrate Ableton Live with modular devices that utilize the Eurorack format.
The full version will be released along with Live 10.1. However, users who meet the requirements below can sign up for the Beta and now download the CV Tools Pack from the Ableton Beta site, Centercode.
Further reading - Live 10 Installing and Managing Packs
Requirements for CV Tools
Live 10 Suite (version 10.1 or above)
Live 10 Standard + Max for Live (version 10.1 or above)
A DC-coupled audio interface (for CV hardware integration)
Best Practices & Safety
- Never send CV directly to your speakers. (Direct voltage can cause damage to your speakers/hearing).
Remember - Eurorack signals are up to 5x louder than line-level audio! Before connecting your modular system to a digital audio interface, be sure to reduce the signal down to line-level using a dedicated output module.
What is a "DC-coupled" audio interface? Why do I need one?
DC-coupling enables hardware devices to send (and, in rare cases, receive) a Direct Current.
However, since audio interfaces are optimized for audio-rate signals, most manufacturers opt for AC-coupled inputs/outputs. AC-coupling filters out ultra-low frequencies, including the types of sustained voltage inherent required for modular synthesis, making them an unreliable method of transmitting CV. For a more comprehensive list of DC-coupled interfaces, please refer to this article from Expert Sleepers.
Tested DC-coupled interfaces:
- Expert Sleepers ES-3 & ES-8
- Motu Ultralite (mk3 or mk4)
- UAD Apollo Series (with some exceptions)
- RME M-32 DA Pro (via optical & coaxial MADI connectors)
Note: Although there are several interfaces on the market with DC-coupled outputs, the only known interface that also contains DC-coupled inputs are the ES Series interface modules made by Expert Sleepers.
I do not have a DC-coupled interface. Can I still use CV Tools?
Yes, even if you are not a modular user, there are interesting things to get out of CV Tools!
- The Rotating Rhythm Generator outputs MIDI, and works great with Drum Racks in Live.
- CV Clock / CV Clock Out / CV Triggers all work without DC-coupled interfaces, since binary events do not generally require exact voltage values.
- The CV In device has a “Pitch” mode, which converts an oscillator’s pitch to CV in real-time (without the use of a DC-coupled input).
- If you have a Eurorack MIDI interface, you can achieve similar results by using Live's External Instrument device.
Can I use CV Tools without any hardware at all?
Yes, CV Tools can be used in a number of creative ways that do not require any hardware.
- Most devices in CV Tools have secondary mapping functions that can map to any parameter within Live.
With the help of ReWire or a virtual audio bus such as Soundflower (Mac) or VB-Cable (Windows), CV Tools can offer some flexible options for cross-program integration with virtual modular emulations that utilize the same concepts of Control Voltage in their signal path (such as VCVRack/Max/Reaktor/et cetera).