This manual is written assuming the reader has basic knowledge of synthesis and sound design. If not, there are a lot of online resources for this information.

Welcome to Coalition!

Using the preset manager:

The preset manager is recommended over your DAW’s preset browser when it comes to navigating any TrapDoor synth. It has been developed to help bridge the gap between browsing systems across various DAWs as well as Mac and PC. Your DAW may randomly not read presets. I am working to correct this. So please make sure you have installed the preset folder in the appropriate destination folder for your system, per the installation instructions.

The signal path:

The sound is generated by the oscillator, passed to the envelope controlled amp, and passed to a choice of one or all three of three different filters. Then either to the effects section or directly out. Envelopes modulate each oscillator’s amplitude, as well as are a modulation option for the filters, in addition to a Sequencer and LFO for the filters.

The filters:

There are two state variable. They operate the same, and the state variable filters get their name from having the options of low pass, high pass, band pass and band reject modes. The FX button will route the output to the effects section.

The oscillators:

The oscillators are running sample based chip modeling waveforms. There are 102 chip waves to choose from. Each osc has it’s own amp envelope and output selection which can be either, or both filters.


In order to create authentic chip sounds, Coalition has extensive pitch modulation, which includes ADSRs, LFO, and note sequencers which are selected on the oscillator you wish to mod. The note sequncers have their own on switches.

The filters have an on switch for their modulators as well as an option for Sequencer, ADSR or LFO (The sequencer also has a secondary on switch to help save resources). The LFO and Sequencer BPM divisions are synced to the host. The AMT knob controls the amount of modulation. Dead center is no modulation. To the right is upward and left is downward.


There are options for mono and glide for you to enjoy. They are independent of any preset information. They will override the voice stealing mode to “soft” and “hard”. When done with these modes, It is recommended that you return the voice stealing mode to “Overlap” for best overall polyphonic performance. As a side note, if you ever experience some clicking that occasionally happens with sample based sound, try different voice stealing modes (and also turn up the oscillator’s attack).

Oversampling will change the overall sound quality by internally oversampling the incoming sample rate. So be careful when using high sample rates to begin with!

If you have any questions, feel free to email me. Have fun!