This is a quick guide to help you discover what Deimos can do.
It assumes you're already comfortable operating instrument plugins and familiar with some synthesis concepts, since plenty of tutorials already exist online.
Deimos tries to capture a lot of flexibility in a compact user interface that feels immediate to use, so here you'll find some tips on reading and interacting with the user interface, as well as some info about certain details of the synth.
Tips for reading the user interface
Modules that are not enabled or not hooked up to anything else will appear grayed out, so you can be sure they won't affect the sound output and are free to use for whatever.
Note that oscillators need to be enabled explicitly in the mixer section: click the labeled knobs below their volume controls.
The small square label on many modules (modulators, oscillators, expression controls) will get a blue outline if the module is used as mod source anywhere. When browsing presets for example, you can immediately see in the top row whether the expression controls (mod wheel, timbre, pressure) are used in them or not.
When hovering any control, have a look at the info bar in the bottom to get a short explanation or reminder about its function.
Discover options using the right mouse button (RMB)
Many options are accessible by left-clicking some selectors. Some selectors can also be enabled or disabled, in which case the right mouse button is used to access their options.
RMB on any modulatable knob shows available modulation sources, if there is still space in the modulation row. Select the desired source to add the new modulation routing.
Oscillator section:
RMB on the selector to the right of the waveform to access various shape modifier modes.
RMB on the mod knob to the left to set FM (-> frequency), PM (-> phase), or SM (-> shape).
RMB on the 1 and 2 labels offers copying/swapping, and setting the osc tuning mode (octave+semi, extended semi, absolute tuning).
Mixer section:
RMB on the oscillator labels to access RM (ring modulation).
Modulation row:
RMB on the source selection to select a second source. Source 1 and 2 will be multiplied. Set "Const" (equals 1) for source 2 to remove it again.
RMB anywhere else on the background to quickly change UI scaling or access synth settings.
Detailed synth tips
Oscillators:
The "Slop" knob to the left adds some per-voice variation and drift to the oscillators, similar to how analog synths might behave. If desired, you can set it to zero and use stable tuning relationships (eg. octaves) which results in stable phase relationships of the oscillators.
Selecting certain shape modifier types will add a second utility knob next to the phase knob to get continuous animation of oscillator phase.
Filter:
The filter has some atypical low-frequency behavior in the HP2 and HP4 modes: when turning up emphasis, you might notice that the HP2 mode actually has a steeper low frequency falloff than the HP4 mode (observe the built-in spectrum analyzer). This is a side effect of the filters internal architecture design. You can notice similar effects also in the BP2 and BP4 modes.
Aliasing and fixed internal sample rate:
I took great care to make sure there's very little aliasing in most situations, but with certain settings and heavy modulation you can still of course still get some. For this and some other reasons, the synth runs at fixed internal sample rate to get consistent results regardless of your hosts sample rate.
This also means you can abuse aliasing as a reliable creative effect if you so desire. One quick way of achieving this is setting LFO rate very high and adding modulation to make it go beyond what the parameter normally offers. Experiment with assign the LFO to different destinations etc.
Note that also other controls can be modulated beyond their normal limits.