The full chain behind Lumicrowd, from a DMX signal on the lighting desk to a glowing crowd: Art-Net or sACN input, a middleware layer that turns raw data into meaningful events, venue mapping, and Server-Sent Events to every phone.

Lumicrowd turns every phone in the room into a controllable pixel - and drives them from the same desk that already runs your lights. Here is the full chain, from a DMX signal to a glowing crowd.

One idea: the audience is a display

A professional show already has a control surface: the lighting operator. Lumicrowd plugs into that world instead of replacing it. The operator sends parameters; Lumicrowd maps them onto the crowd in real time. No new creative language, no separate timeline to babysit.

Step 1 - Input: DMX over IP

Your lighting desk speaks DMX. Over a network that becomes Art-Net or sACN (ANSI E1.31) - DMX-over-IP protocols that carry 512-channel "universes" as continuous UDP updates. Lumicrowd listens passively on the network: it never sits in the critical path of your fixtures, so it cannot break the show it rides on.

Step 2 - Middleware: from stream to meaning

Raw DMX is a firehose of 0-255 values. Phones have no use for that. A middleware layer turns it into something meaningful:

Filtering - only act on changes that matter
Thresholds + hysteresis - a value has to clearly cross a line before it flips, so effects do not flap on and off around the edge
State tracking - emit discrete events (start, stop, switch, zone change) instead of a raw stream

The result is predictable behaviour under stress - which, at crowd scale, is the actual product.

Step 3 - Mapping: the venue as a canvas

The server applies your venue layout. Every seat is a deterministic pixel with a fixed position, so an effect "knows" where it lands - a flat floor behaves very differently from a tiered bowl or a dome. Effects are expressed in normalized space and resolved to real seats and zones. More on that in our venue-mapping deep-dive.

Step 4 - Delivery: Server-Sent Events

Each phone holds a lightweight, persistent SSE connection and renders the colour for its own seat. We chose SSE deliberately:

low, predictable latency over a connection that stays open
automatic reconnection when a phone drops
efficient on bandwidth - we push discrete events, not raw frames
works behind most firewalls, with no special client

No app, no wearable - the crowd already holds the display in their hands.

Proven in the field

At Citymesh's 20th anniversary, this exact chain held 200 phones connected simultaneously - from 1 to 200 in about three minutes - with zero errors and no server restart. Read the full case study.

The takeaway

The magic is not one clever animation. It is a system built like a live-production tool: non-invasive input, meaningful events, deterministic mapping, and a delivery channel designed for timing and reliability. That is what lets a whole room light up as one.

From the lighting desk to the crowd: how Lumicrowd works