Lumen & Echo

WASDWalk MouseLook around ShiftSprint SpaceJump Walk into a wallThe wall becomes your floor (jump into a ceiling to stand on it) GReturn to normal gravity Hold ECarry a sound emitter, release to leave it floating in place ScrollMove a carried emitter closer or farther RToggle ray tracing on and off to compare PShow the traced sound paths EscPause and open these settings

Wall walking

Headphones give the most precise 3D sound. Stand still to let the path tracer converge to a noise-free image.

Path tracing (off = fast raster preview)

Light bounces

Samples per pixel

Denoiser passes

Firefly clamp

Converge to a reference image while standing still

Spectral dispersion (rainbows through crystal and flint glass)

Render scale

Exposure

Bloom

HDR output (extended range on HDR displays)

Speaker setup

Master volume

Reverb amount

Sound rays per emitter

Sound bounces

Early reflections

Channel spread

Doppler effect (pitch shifts with movement, as in reality)

Show traced sound paths (dashed: heard through a wall)

Sound is traced in eight octave bands from 63 Hz to 8 kHz. Multichannel files play each channel from its own position around the emitter. Audio runs at the device's native sample rate in 32-bit float throughout; uploaded WAV and FLAC files stay lossless.