Resynthesis (teaching)

ambiscape resynth recreates a session's soundscape from layers of basic synthesis models and renders the result as one self-contained Web Audio page — no samples, no external resources, one HTML file you can open anywhere or hand to students.

ambiscape resynth SESSION/        # writes SESSION/resynthesis/index.html

Needs a prior analyze run; it also reads whatever module JSONs exist (tonality, modulation, spatial, summary) and degrades gracefully when one is missing.

Why

The page is teaching material: a real place, decomposed into the four canonical building blocks of a synthesis course, with every starting value measured from the recording. Students toggle layers to hear how a soundscape is assembled, then drag sliders to exaggerate or delete each ingredient. Comparing two sessions' pages (say, a station and a train carriage) shows how few parameters carry a place's identity.

The four layers

Layer	Synthesis model	Measured parameters
Bed	subtractive: white noise → per-octave peaking filters	10th-percentile octave spectrum (the keynote as a filter curve)
Machine	additive: detuned oscillator pair per tonal line, shared AM LFO	tonal-track frequencies and prominences; micro-modulation rate and depth
Events	stochastic: Poisson-scheduled band-passed noise bursts; occasional pass-by swell	events/min, median event duration, spectral centroid, pass-by count/duration
Space	per-source panning + two cross-fed delays	diffuseness ψ (diffusion wet), azimuthal concentration R (panning spread)

Recipe

The mapping lives in resynthesis/recipe.json (also embedded in the page), produced by resynth.build_recipe(sess, F, analysis_dir). The recipe is deliberately small and human-readable — it is the lesson: a place, reduced to a couple of dozen numbers, remains recognizable.

from ambiscape import features, resynth
import ambiscape as asc

sess = asc.open_session("2026-07-28-Antwerpen-train-station")
F = features.load_features(features.extract_session(sess, "analysis/features"))
doc = resynth.run_session(sess, F, "2026-07-28-Antwerpen-train-station/analysis")