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docs/engine_space.md

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+# Space & Time
+
+Spatial effects position sounds in the stereo field and add depth through delays and reverbs.
+
+## Pan
+
+Pan positions a sound in the stereo field.
+
+```forth
+hat -0.5 pan .               ( slightly left )
+perc 1 pan .                 ( hard right )
+kick 0 pan .                 ( center )
+```
+
+| Parameter | Range | Description |
+|-----------|-------|-------------|
+| `pan` | -1 to 1 | Stereo position (-1 = left, 0 = center, 1 = right) |
+
+## Width
+
+Width controls the stereo spread using mid-side processing.
+
+```forth
+pad 1.5 width .              ( wider stereo )
+pad 0 width .                ( mono )
+```
+
+| Parameter | Range | Description |
+|-----------|-------|-------------|
+| `width` | 0+ | Stereo width (0 = mono, 1 = unchanged, 2 = exaggerated) |
+
+## Haas Effect
+
+The Haas effect delays one channel slightly, creating a sense of stereo width and spatial placement.
+
+```forth
+snare 15 haas .              ( 15ms delay on right channel )
+```
+
+| Parameter | Range | Description |
+|-----------|-------|-------------|
+| `haas` | ms | Delay time (1-10ms = subtle width, 10-35ms = distinct echo) |
+
+## Delay
+
+Delay is a send effect that creates echoes. The `delay` parameter sets how much signal is sent to the delay bus.
+
+```forth
+snare 0.3 delay 0.25 delaytime 0.5 delayfeedback .
+```
+
+| Parameter | Range | Description |
+|-----------|-------|-------------|
+| `delay` | 0-1 | Send level |
+| `delaytime` | seconds | Delay time |
+| `delayfeedback` | 0-0.95 | Feedback amount |
+| `delaytype` | type | Delay algorithm |
+
+### Delay Types
+
+| Type | Description |
+|------|-------------|
+| `standard` | Clean digital repeats |
+| `pingpong` | Bounces between left and right |
+| `tape` | Each repeat gets darker (analog warmth) |
+| `multitap` | 4 taps with swing control via feedback |
+
+```forth
+snare 0.4 delay pingpong delaytype .
+pad 0.3 delay tape delaytype .
+```
+
+## Reverb
+
+Reverb is a send effect that simulates acoustic spaces. The `verb` parameter sets the send level.
+
+```forth
+snare 0.2 verb 2 verbdecay .
+pad 0.4 verb 4 verbdecay 0.7 verbdamp .
+```
+
+| Parameter | Range | Description |
+|-----------|-------|-------------|
+| `verb` | 0-1 | Send level |
+| `verbdecay` | seconds | Reverb tail length |
+| `verbdamp` | 0-1 | High frequency damping |
+| `verbpredelay` | ms | Initial delay before reverb |
+| `verbdiff` | 0-1 | Diffusion (smears transients) |
+| `verbtype` | type | Reverb algorithm |
+
+### Reverb Types
+
+| Type | Description |
+|------|-------------|
+| `dattorro` | Plate reverb, bright and metallic shimmer |
+| `fdn` | Hall reverb, dense and smooth |
+
+```forth
+snare 0.3 verb dattorro verbtype .   ( plate )
+pad 0.5 verb fdn verbtype .          ( hall )
+```
+
+## Comb Filter
+
+The comb filter creates resonant pitched delays, useful for Karplus-Strong string synthesis and metallic tones.
+
+```forth
+white 0.5 comb 220 combfreq 0.9 combfeedback .   ( plucked string )
+```
+
+| Parameter | Range | Description |
+|-----------|-------|-------------|
+| `comb` | 0-1 | Send level |
+| `combfreq` | Hz | Resonant frequency |
+| `combfeedback` | 0-0.99 | Feedback (higher = longer decay) |
+| `combdamp` | 0-1 | High frequency damping |
+
+Higher feedback creates longer, ringing tones. Add damping for more natural string-like decay.