Voltage Controlled Cassette Organ Get it

Voltage Controlled Cassette Organ

I discovered that the Korg CX-3, when sampled through cassette tape, introduced some imperfections that transformed the sound.

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The wow and flutter effects, along with the random warbles, created a fascinating movement reminiscent of a chorus/vibrato or the doppler effect from a rotary speaker. However, unlike traditional modulation effects with fixed speed, the cassette tape introduced a more random and organic quality to the modulation.

You'll get the iconic sound of the Korg CX-3, infused with the unmistakable charm of cassette tape recording, with the Voltage Controlled Cassette Organ. It captures the essence of the organs analog oscillators as well as the pitch fluctuation (wow/flutter), harmonic distortion, and coloration associated with cassette tape recordings.

Each note for every drawbar, as well as the sound of the key click, has been meticulously sampled as individual audio files, ensuring authenticity and attention to detail. To achieve an even richer sound, the organ has been recorded twice onto cassette tape, resulting in a double-track effect that adds depth and character. Thanks to the inherent idiosyncrasies of tape deck mechanics and the tape itself, each playback yields a slightly different result.

It also includes impulse responses for two tape delay/echo types and two room reverbs.

Voltage Controlled Cassette Organ plugin interface, showing its controls and on-screen keyboard

Video

A demonstration of the Voltage Controlled Cassette Organ library for Decent Sampler.

Voltage Controlled Cassette Organ - Sound Examples Video page · Watch on YouTube

Included formats

  • VST3 (macOS)
  • AU (macOS)
  • Standalone application (macOS)
  • Decent Sampler (macOS, Windows and Linux)

The plugin version is currently released for macOS only. Windows and Linux versions are planned. Until then, the Decent Sampler version covers those platforms.

The plugin version

The plugin is a self-contained instrument, available as VST3, AU and Standalone. Samples, graphics and impulse responses are all embedded in the plugin itself, losslessly compressed, so there are no external files to install or locate. Only the samples for the selected preset are loaded into memory, and a fresh instance lets you choose which preset to load before anything is decoded.

The plugin has all the controls and features from the Decent Sampler version, including MIDI learn, the master volume fader with output meter, value readouts for the knobs and full DAW automation. On top of that, the plugin version adds:

  • Drift wheels next to the pitch and modulation wheels, adding a subtle random pitch and volume drift to each voice.
  • A velocity curve setting in the settings menu.

The Decent Sampler version

This version of Voltage Controlled Cassette Organ is an instrument preset / sample library for Decent Sampler. If you're new to Decent Sampler, I recommend checking out this guide first.

Technical specification

Sample rateBit depthChannelsNumber of filesFile size
Samples48 kHz24 bit1 (mono)12203.46 GB
Impulse responses48 kHz24 bit2 (stereo)43.60 MB

Instrument presets

To ensure optimal performance and flexibility, the instrument offers three presets: A quite resource-intensive "All Drawbars" preset with 9 drawbars, a lighter "All Drawbars (Lite)" preset, and a "Single Drawbar" preset which conserves resources by playing back fewer samples per key. The "Single Drawbar" preset does however have samples from different drawbars for an extended key range.

All Drawbars

The "All Drawbars" preset plays back 20 different samples per note, resulting in a rich and complex sound. However, it does demand significant system resources, especially when playing big chords.

All Drawbars (Lite)

A lighter variant of the "All Drawbars" preset. It has no "Double track" feature and shares samples between drawbars to reduce the sample count, which lowers the memory use.

Single Drawbar

User interface for the "Single Drawbar" preset
User interface for the "Single Drawbar" preset

As a more resource-friendly alternative, the "Single Drawbar" preset plays back only four samples per key. This preset also incorporates additional knobs for adjusting the envelope decay curve and release curve, maximizing your creative control.

User Interface

The user interface offers precise control over every aspect of the instrument and effects. Explore parameters to refine your sound, including control over the nine drawbars, key click volume, envelope, amplitude modulation with LFOs, double track, and the immersive effects of echo and reverb.

ADSR Envelope

Envelope controls for the "All Drawbars" preset
Envelope controls for the "All Drawbars" preset
Envelope controls for the "Single Drawbar" preset
Envelope controls for the "Single Drawbar" preset

Shape your sound precisely with the Attack, Decay, Sustain, and Release parameters. Whether you desire a punchy, staccato tone or a smooth, lingering ambiance, the ADSR envelope allows you to tailor the dynamics to your liking.

  • Attack
    • Individual attack time of the amplitude envelope for each drawbar
  • Decay
    • Individual decay time of the amplitude envelope for each drawbar
  • Sustain
    • Individual sustain level of the amplitude envelope for each drawbar
  • Release
    • Individual release time of the amplitude envelope for each drawbar

Envelope curves

Controls for envelope curves
Controls for envelope curves

For even more control over the envelope, you can change the curve of the attack time. The "Single Drawbar" preset also incorporates two additional knobs for decay curve and release curve. The decay curve and release curve are exponential for the "All Drawbars" preset.

  • Attack curve
    • Adjusts the curve of the attack time from logarithmic to exponential with linear in the middle
  • Decay curve
    • Adjusts the curve of the decay time from logarithmic to exponential with linear in the middle
  • Release curve
    • Adjusts the curve of the release time from logarithmic to exponential with linear in the middle

LFO

LFO controls for the "All Drawbars" preset
LFO controls for the "All Drawbars" preset
LFO controls for the "Single Drawbar" preset
LFO controls for the "All Drawbars" preset

The LFO Rate and LFO Depth knobs enable you to modulate the amplitude of the drawbars with the desired depth and rate using the Low-Frequency Oscillator (LFO), opening up a world of rhythmic possibilities.

  • LFO Rate
    • LFO rate determines the speed at which the modulation occurs
  • LFO Depth
    • Adjust the LFO depth to introduce subtle or pronounced variations in volume

Drawbars

Drawbar controls for the "All Drawbars" preset
Drawbar controls for the "All Drawbars" preset

Unleash the power of the nine drawbars to shape your organ's tone with precision. Each drawbar controls the amplitude of a specific harmonic overtone, offering you unparalleled control over the instrument's harmonic richness.

Key click

Volume control for the "key click" sound
Volume control for the "key click" sound

During the early production of Hammond organs, a seemingly unintentional and unwanted occurrence was observed: a distinctive click or pop sound that accompanied the pressing of a key. Initially, this peculiar phenomenon was perceived as a manufacturing flaw or an undesirable artifact of the instrument. Efforts were made to mitigate or eliminate the clicking sound, as it was not part of the intended design.

Musicians discovered that this inadvertent click, which was initially considered a fault, actually contributed a unique and appealing quality to the instrument's overall sound. Rather than viewing it as an unwanted artifact, musicians started to appreciate the click as a distinct characteristic that added depth and character to their performances.

The click's percussive nature, akin to the striking of a mallet on a percussion instrument, provided a lively and vibrant attack to the notes played on the organ.

Double track

Button controls for the "double track" effect
Button controls for the "double track" effect

Each sample has been recorded twice and can be mixed together for a "chorus" effect or panned for a stereo effect.

Because of the nature of the tape deck mechanics and the tape itself, the sound will be a bit different for every time it's recorded and played back.

Controls

  • On
    • Turns on or off the double track samples
  • Stereo
    • Toggle between both tracks in center (mono) or one track panned left and one track panned right (stereo).

Effects

These effects are achieved using carefully crafted impulse responses. The echo effect employs a Fulltone Tube Tape Echo recorded twice for stereo, while the reverb effect draws from a Chase Bliss Audio & Meris CXM 1978 reverb pedal with a room setting.

Echo

Controls for the tape echo impulse response
Controls for the tape echo impulse response

Select from two distinctive echo options: the short echo, delivering a classic slapback effect, and the long echo, characterized by a slower decay and numerous repeats.

  • On
    • Turns the echo on and off
  • Long
    • Switches between a short slapback echo and a long echo with slow repeats and high feedback
  • Mix
    • Mix between direct signal and echo signal

Reverb

Controls for the room reverb impulse response
Controls for the room reverb impulse response

You'll also find two reverb effects: the short reverb, evoking the intimacy of a small room, and the long reverb, enveloping your sound in the vastness of a spacious environment.

  • On
    • Turns the reverb on and off
  • Long
    • Switches between a short/small room reverb and a long/big room reverb
  • Mix
    • Mix between direct signal and reverb signal

Release notes

Version 2.1.02026-08-01

The changes in this release apply to the plugin version only. The DecentSampler version is unchanged.

  • Added a translucent overlay graphic on top of the interface.
  • Keys that are hovered or held on the keyboard are now shaded in a neutral way instead of turning yellow:
    • White keys turn darker.
    • Black keys turn brighter.
  • The computer keyboard keeps playing notes even while you adjust a control with the mouse.
Version 2.0.02026-07-19
  • Added a plugin version. See the section "The plugin version".
  • Corrected the UI values for the drawbars, the envelopes, the LFO and the key click amount.
  • Fixed the translationOutputMax value for the LFO depth.
  • Fixed dead default attributes.
  • Effect bindings now use effectIndex, and empty effects elements were removed.
Version 1.3.02025-01-04
  • Removed amplitude envelope for one shot samples
Version 1.2.02023-07-05
  • Added "All Drawbars (Lite)" preset
    • No "Double track" feature
    • Shares samples between drawbars to reduce sample count
  • Set default decay curve and release curve for "Single Drawbar" preset to exponential
  • Minor GUI adjustments
Version 1.1.02023-07-03
  • Fix mouse drag direction for drawbars
Version 1.0.02023-06-26
  • First version released

About this repository

This repository contains the source for both the Decent Sampler library (the DecentSampler folder) and the plugin version. The plugin is a thin wrapper around the shared Dehli Musikk sampler engine, and a converter translates the Decent Sampler library into the engine's native preset format at build time. The audio files are not part of this repository, since the samples are a paid product. The full version is available from store.dehlimusikk.no.