Honk Orchestra
The street is the band. Honk Orchestra listens to the world around you and turns every horn,
pressure-cooker whistle, bird chirp and doorbell into music, live. Your first honk sets the key, each
sound gets tuned and dropped into a beat, and one honk becomes a little riff. A traffic jam becomes a song.
Play it now: https://mark-alexander-hub.github.io/honk-orchestra/ (any phone or laptop, nothing to install)
Quick start
- Live: tap Start the band, hold the phone towards the traffic. Each horn becomes a note. Tap a burst to replay it.
- Collect on the way: choose Sound, Voice or Hum, name or tag it, tap Grab, tap again to stop.
- Studio at night: pick the day and a style, tap Video if you want one, then Make my song. Name it, Save or Share.
- Deck: play the pads, drag the FX pad, hold to build and let go to drop. Shake for a drop.
The same guide is inside the app and the page: tap How to use at the top.
Day Mix: collect your day, get a song tonight
- Collect: tap Grab whenever you hear something good (a horn, the chai stall, a temple bell, rain,
someone humming) and it keeps a clip of up to 15 seconds on your phone. You can also add recordings
you already have.
- Studio: at night, pick a day and a style and tap Make my song. It finds the notes in every clip
and arranges about a minute of music: the day's sounds over a drone, the beat coming in, full swing,
and an ending where the drums drop out and your last sound rings off. The song is saved and ready to share.
- Qawwali style: harmonium drone, dholak in keherwa, a crowd of hand-claps, and the tempo climbs
through the last part the way a qawwali does.
- Each clip is also a pad you can tap to play its sound on the beat, and ✕ leaves a clip out.
Voice, hum, tags and auto-grab
In Collect, pick what you're grabbing:
- Sound (default): horns, bells, whistles. Tag it (Horn, Chai, Temple, Bus, Rain, Bird, Office) and
the tag shows on the pad and in the song's file name.
- Voice: say something ("Good morning Bangalore!"). The Studio cuts it into syllable chops and rides
them on the beat like a DJ vocal. Tap its pad for a stutter.
- Hum: hum a tune. The Studio finds the notes, moves them into the song's key and plays them back
as the lead: a plucked sitar-like string in Qawwali and Dhol, a flute in Lo-fi, a synth in Techno.
- Auto-grab horns: leave Collect open on the dashboard and every horn that goes by is kept as a
3-second clip. It uses the microphone and battery while the tab is open, so it's off by default.
Video, week mix
- Video: press the Video toggle next to Make my song and you get a portrait .mp4 with the bursts
popping on the beat, ready for WhatsApp Status or a Reel (Chrome and the app; browsers without mp4
recording give a .webm).
- Week mix: plays the last seven days' songs back to back, with a filter sweep between days, as one
recording.
The Deck tab
Its own screen, nothing scrolls, so every drag is a DJ move. Your clips sit along the top as pads:
- FX pad: drag left to close a low-pass filter (the "underwater" sweep), right to open a high-pass,
up for echo and reverb. Let go and it snaps back clean.
- Hold to build: the kick and bass drop out, a snare roll speeds up and a riser climbs. Let go and it
drops on the next downbeat with a crash and a sub boom. Make my song does this by itself before the claps come in.
- Scratch: a vinyl scratch on the last sound that played.
- Hold to repeat: stutters the last half-beat of the whole mix for as long as you hold.
- Mixer: faders and mutes for Drums, Bass, Drone, Sounds and Lead.
- Tilt FX: lean the phone left or right to sweep the filter without touching the pad.
- Shake the phone to drop (or for a crash and a boom), and tap a burst on the Live screen to play it again.
Clips stay in the browser's storage on your phone (in the app, inside the app). Nothing is uploaded.
Live
- Listens for tonal sounds: horns, whistles, chirps, bells, humming. Talking, claps and traffic
rumble don't have a clear pitch, so they pass through.
- Tunes them to the key set by the first honk and plays them back on the beat as a short riff
(each honk repeats up the scale a few times, then fades out).
- Four bands: Lo-fi, Dhol, Techno and Qawwali.
- Remix a file: pick any recording or video on your phone and the band plays along with it.
- Record 30 s and share the remix. A little of the real street goes into the recording for atmosphere.
- Fake honk for trying it at a quiet desk.
On a phone speaker it ignores its own notes and drums, so it doesn't feed back on itself. Earphones
sound best.
The app
The Android app is the same page, with the screen kept awake and recordings saved to
Downloads/Honk Orchestra and shared straight to WhatsApp. Install it with Obtainium (badge above)
or download the APK from Releases. Android 8 and newer.
Privacy
The microphone is analysed live, a twentieth of a second at a time, and nothing is uploaded. The page
has no analytics and no server. Only a recording you choose to make is saved, on your phone. The only
thing fetched from the internet is the font.
How it hears a honk
Every 21 ms it takes a 4096-point FFT and compares it with a slowly learned picture of the street's
background noise. A honk is a narrow peak far above that background, the lowest of its overtones (voices
have a strong partner at half their pitch; horns don't), holding the same pitch for about a tenth of a
second. The captured snippet is resampled to the nearest note of the scale. Everything is plain Web Audio
in one index.html; no libraries.
Build the app
cd android
gradlew assembleDebug
The build copies index.html into the app, so the website and the app are always the same.
Licence
MIT. Built by Mark Isidore Nicholas Alexander.
