CV Mod

CV Mod is a 2 LFO/VCO Oscillator Module meant to be used with modular or semi-modular synth hardware. Simply connect the headphone output of your iPhone or iPad to one or more CV or audio inputs on your hardware.

To get the most out of this module, use a stereo breakout cable to separate the left and right audio channels. Just like that, you now have 2 additional LFOs or full range oscillators added to your rig!

CV Mod can also send out signals via a connected DC-coupled audio interface. With Audiobus 3 and Inter-app audio support, you'll have an easier time routing CV Mod's outputs to wherever you need them to go.

In the spirit of modular synthesis, you have complete control over each oscillator’s parameters via external MIDI. You can also modulate one oscillator’s frequency and phase with the other oscillator’s rate and depth controls.

With two drawable wave table editors, you can create whatever crazy wave forms you like, unleashing a vast sea of possibilities. Instant grit!

Intuitive controls via the main faders, XY pad, or MIDI CC make this an incredibly easy way to add more modulation and sound sources to your gear. Download now and have some good old-yet-new-fashioned creative fun!

Key Features:

2 Oscillators that function as LFOs or sound sources with 5 frequency ranges: 1 Hz, 4 Hz, 40 Hz, 120 Hz, and VCO mode (full range). This wide set of ranges allows for ultra slow ambient filter sweeps and rip roaring ring-mod madness
Choose from 8 different waveforms: Sine, Triangle, Sawtooth, Reverse Sawtooth, Square, Random, and two user defined shapes
Wave Table grid editor allows you to draw 2 custom waveforms
Each oscillator has its own envelope generator, which can be synchronized to subdivisions of the current tempo or the rate of one of the oscillators
Multi-touch control of each oscillator’s rate, depth, and phase with easy to use faders
Fine tuning control of each oscillator, + or - one octave
Separate glide controls for each oscillator, with a configurable maximum glide time of 120 seconds!
MIDI Keyboard control of an oscillator’s frequency allows you to play notes and use this app as an additional sound source in VCO mode
Duophonic mode allows you to play two notes at once when both oscillators are controlled by MIDI keyboard in VCO mode
XY Pad allows you to control up to 3 parameters, with the Z-axis mapped to touch pressure (if your device supports it)
Tempo Sync feature that constrains each oscillator’s rate to subdivisions of the current tempo, when operating in one of the LFO modes
Rich MIDI implementation allows you to control all oscillator settings via MIDI CC with MIDI learn. In addition, you can control each oscillator’s rate and the overall depth via pitch wheel, mod wheel, velocity, aftertouch, and note values (key tracking)
Cross modulation capabilities allow you to modulate one oscillator’s phase and frequency with the rate and depth of the other oscillator
Turn either oscillator into a trigger pulse, which can be synchronized to subdivisions of the current tempo or the rate of the other oscillator
Save sessions as presets and save custom wave tables created with the wave table editor
Audiobus 3 and Inter-app audio support

Other settings include:

Tempo override from external MIDI clock
Pitch bender range control (maximum of 2 octaves)
Background audio mode
Oscillator pan controls: each oscillator can be panned to the left channel, right channel, or center
Aftertouch sensitivity control (allows you to take it easy on those older keybeds)
Bit depth resolution reduction controls for each oscillator, which opens up even more possibilities

CV Mod proudly uses the open source AudioKit framework for the oscillators and MIDI. Visit audiokit.io for more info.

Screenshots

New Features in 1.2.0

Older Screenshots

Demonstrations

The stereo breakout cable used in the demonstration videos can be purchased here: https://www.sweetwater.com/store/detail/YMM261--hosa-ymm-261-6-inch

User Guide

CV Mod is a 2 LFO/VCO Oscillator Module meant to be used with modular or semi-modular hardware. Simply connect the headphone output of the iOS device to one or more CV (or audio) inputs on your hardware. For best results, ensure that the volume of the iOS device is set to maximum. (Don't forget to turn the volume down afterwards!) To get the most out of this module, you should use a stereo breakout cable (a cable that can separate the left and right audio channels). By default, Oscillator 1 is mapped to the left stereo channel and Oscillator 2 is mapped to the right channel. This can be changed in the settings. CV Mod can also be used as an input source to other apps as part of an Audiobus 3 or Inter-app audio session (for apps that have the ability to receive another app's audio stream via Audiobus 3 or Inter-app audio). Please read the doc below for more details.

Top Menu Bar

Power Button
Not hearing results? Be sure that everything is plugged in and that you've turned the power switch on. It's orange when on and black when off.
MIDI
Connect an external MIDI source or multiple sources to control various parameters. For example, you might want to control an oscillator's frequency with the keys on a MIDI keyboard. You could also map the pitch wheel, mod wheel, velocity, and aftertouch to control oscillator rates or the master depth. In addition, you might want to have MIDI clock messages override the internal clock and tempo.

In the connections window, you can configure the following:
- Notes: receive MIDI note on/off data from the device. This also includes mod wheel, pitch bend, and aftertouch messages. Tap "Notes" to enable and tap on the adjacent field to choose a specific MIDI channel or all MIDI channels.
- Ctrl: receive MIDI CC messages from the device for the purpose of controlling CV Mod's parameters via MIDI learn. Tap "Ctrl" to enable and tap on the adjacent field to choose a specific MIDI channel or all MIDI channels.
- TP: receive transport messages (stop, start, continue) from the device. Incoming transport messages can be used to start and stop the oscillators. Tap "TP" to enable.
- Clock: receive MIDI clock from the device. Tap "Clock" to enable.

Use the Learn menu option to map a control to an incoming MIDI CC source. Simply select the control from the sub-menu that you want to map to, and then send a CC message (i.e., turn a knob) via an external MIDI source to complete the mapping.
MD
Control the master depth (output volume) with an external MIDI source or with the X, Y, or Z axis (pressure) of the XY pad.
C1
Control the rate (frequency) of oscillator 1 with an external MIDI source or with the X, Y, or Z axis (pressure) of the XY pad.
C2
Control the rate (frequency) of oscillator 2 with an external MIDI source or with the X, Y, or Z axis (pressure) of the XY pad.
R1
Set the upper limit of the frequency range of oscillator 1. If this is set to the highest level, labeled VCO, and C1 is set to Midi KBD, the frequency will be mapped to that of the corresponding MIDI note.
R2
Set the upper limit of the frequency range of oscillator 2. If this is set to the highest level, labeled VCO, and C2 is set to Midi KBD, the frequency will be mapped to that of the corresponding MIDI note.
O1
Set the wave shape of oscillator 1. WT1 and WT2 default to triangle if they haven't been set. You can also set the shape by tapping on the name of the wave shape in the Main Control view.
O2
Set the wave shape of oscillator 2. WT1 and WT2 default to triangle if they haven't been set. You can also set the shape by tapping on the name of the wave shape in the Main Control view.

Bottom Menu Bar

P1
The rate and depth of oscillator 2 will be used to modulate the phase of oscillator 1.
P2
The rate and depth of oscillator 1 will be used to modulate the phase of oscillator 2.
F1
The rate and depth of oscillator 2 will be used to modulate the frequency of oscillator 1.
F2
The rate and depth of oscillator 1 will be used to modulate the frequency of oscillator 2.
EG
Open the Envelope Generator view.
WT
Open the Wave Table Editor to edit Wave Table 1 or Wave Table 2.
XY
Open the XY Pad
Ctrl
Open the Main Control view

Main Control View

The Main Control view provides controls for both oscillators. From here, you can control the wave shape, tuning, rate, depth, phase, and glide of each oscillator. You can also mute the audio output of an oscillator.

CV1/CV2
Mute or unmute the output of the oscillator. This does not affect any modulation between the oscillators, it simply supresses the audio output.
Wave Shape Name
You can change the wave shape of the oscillator by pressing the shape name currently displayed.
T
Fine tune the oscillator with the tuning slider. Press T to reset the tuning.
K
Quick access button for controlling the oscillator's frequency via external MIDI Keyboard (MIDI note on/off messages)
Drive
Increase the scale of the oscillator's amplitude by a factor of 10. Please be careful when wearing headphones.
Sync
Synchronize the rate of the oscillator to subdivisions of the current tempo.
Trig
Send out a trigger pulse at a given rate. The rate can be that of the other oscillator or a clock subdivision of the current tempo. You can still use the fine tuning control.
Rate
Control the rate (frequency) of the oscillator.
Depth
Control the depth (output volume) of the oscillator. This is also used to control the depth of internal modulation between oscillators.
Phase
Control the phase offset of the oscillator. Modulating the phase of a square wave produces an effect similar to pulse width modulation (PWM).
G
Adjust the glide (portamento) time of the oscillator. The maximum time can be adjusted (up to 120 seconds) in the settings.

Each oscillator has its own dedicated ADSR envelope generator, which can be used to modulate the amplitude and frequency to varying degrees. The maximum time for attack, decay, and release can be configured in the Settings.

A
Sets the duration of the attack phase.
D
Sets the duration of the decay phase.
S
Sets the sustain level.
R
Sets the duration of the release phase.
Amp
Increase or decrease the effect of the envelope generator on the oscillator's amplitude.
Freq
Increase or decrease the effect of the envelope generator on the oscillator's frequency (pitch).
AT
Increase the effect of the envelope generator with MIDI Aftertouch messages.
EG 1 / EG 2
Enable or disable the envelope generator for the respective oscillator.
Trig
Trigger the envelope manually by pressing the Trig button. When the Trig button is highlighted, it is either in the attack, decay, or sustain phase. Press Trig again to initiate the release phase.
Sync
Trigger the envelope with subdivisions of the current tempo. Press Sync and select the subdivision you want.
Key
Trigger the envelope with MIDI note on/off messages.
Inv
Invert the modulation effect that the envelope generator has on its destinations.
Copy
Copy all settings from EG 1 to EG 2

You can create 2 of your own wave forms per session with the wave table grid editor. Simply drag your finger along the grid to create a wave shape. Press the Clear button to erase the currently stored wave form. Note: Your wave form must reach the end of the x-axis before it can be used. Save and recall wave table presets with the Presets button.

XY Pad

The XY pad can be used to control oscillator rates and master depth when mapped via C1, C2, and MD in the top menu bar. The Z-axis responds to touch pressure (not available on all devices).

Settings

Tap the Gear icon to open the menu.

Save presets by choosing Presets from the menu. Choose "Save New" and enter a name to save a preset. Load a previously saved preset by tapping on the name. Delete a preset by clicking on the "X" button next to the name. Select "Init" to return to the default state.

Main Settings

Glide Time
Sets the maximum glide time in seconds (up to 120).
EG Time
Sets the maximum envelope attack, decay, and release time in seconds (up to 120).
Tempo
Sets the internal tempo in BPM. This will be automatically overridden by any incoming MIDI clock source.
Bender Range
Sets the maximum range allowed by incoming MIDI pitch wheel messages (up to 2 octaves).
Mono/Duo
When both oscillators are in VCO mode and are set to be controlled by Midi KBD, enabling Duo mode allows you to play 2 notes at once. The lower note controls oscillator 1 and the higher note controls oscillator 2. In Mono mode, both oscillators will be set to the frequency of the last incoming note.
Hard Tempo Sync
Oscillators that are in LFO mode with sync enabled will restart every time a tempo change is detected.
BG Audio
Audio output will continue when the app is put in background mode if this is enabled.
Osc 1 Pan
Sets the stereo channel of Oscillator 1. (Left, Right, or Center)
Osc 2 Pan
Sets the stereo channel of Oscillator 2. (Left, Right, or Center)
AT Sensitivity
Adjust the sensitivity for responding to incoming MIDI Aftertouch messages. Some MIDI keyboards transmit a wider range of values than others.
Osc 1 Res
Increase or decrease the bit depth of oscillator 1.
Osc 2 Res
Increase or decrease the bit depth of oscillator 2.

Audiobus and Inter-app audio

CV Mod can send its output to other apps as part of an Audiobus 3 or Inter-app audio signal chain. Note: When CV Mod is connected to an Audiobus or Inter-app audio session, the audio stream will become active if it isn't already. This means that you will not be able to turn off the audio stream like you normally would via the "Power button". However, you can still mute both oscillators as described above by deselecting the "CV1" and "CV2" buttons. Background audio must also remain enabled while connected to an Audiobus or Inter-app audio session. Once the session is terminated, CV Mod's background audio setting will be used to either enable or disable audio when the app is running in the background.

Please send support requests, comments, or concerns to eokuwwy@gmail.com

eokuwwy.com

CV Mod proudly uses the AudioKit open source framework. Visit AudioKit.io for more info.