Color Echo

How Color Echo works

Four pads light up in an order you have to reproduce. The first round is one pad long; get it right and the same pattern comes back with one more pad on the end. Get one wrong — or run out of time — and the run is over. Your score is the number of rounds you repeated in full.

The pattern is append-only. Round five is round four plus one new pad, in the same order, so nothing you have already learned is ever thrown away. That is what makes the game playable at all: you are not memorising a fresh sequence every round, you are extending one you already know by a single item.

Every pad says what it is three times over

A pad is a colour, a shape and a note, and all three carry the same information. That is deliberate rather than decorative — a game that identifies its pads by colour alone is unplayable for a significant number of people, and unpleasant for anyone playing on a washed-out phone screen in daylight.

• Amber, a circle — the note A below middle C.
• Rose, a triangle — C♯.
• Teal, a square — E.
• Violet, a diamond — the A an octave above the first.

Those four notes are an A major chord with the octave on top, which is the same set the 1978 toy used. A chord rather than a scale matters more than it sounds like it should: any two of these pads are consonant together, so a fast run stays musical instead of turning into noise, and the octave between the outer two is the interval people identify most reliably by ear. Plenty of players end up following the tune rather than the lights without ever deciding to.

Two clocks, and both of them speed up

The difficulty is not just that the pattern gets longer. Two separate timings tighten as you go, and they are what turn a memory test into a nerve test.

• The playback gets faster. In round one each pad takes 640 milliseconds — 397 lit, 243 dark. That shortens by 24 milliseconds a round until it hits a floor of 280 (174 lit, 106 dark) at round sixteen. At the floor the pattern arrives at about 3.6 pads a second.
• The clock on each press gets shorter. You start with 2.4 seconds per pad, losing a tenth of a second a round down to a floor of 0.9 seconds — also at round sixteen. The clock is per press and resets every time you get one right, so a long pattern is not penalised for being long; the ninth pad gets the same window as the first.

Both curves bottom out at the same round on purpose. Past round sixteen nothing gets faster, so a long run is a test of memory alone rather than of a difficulty that never stops moving. Playback for round one takes 1.34 seconds including the pause before it starts; by round ten it is 4.94, and by round twenty-five 7.7.

The gap between two flashes never closes, at any round — the lit time is a fraction of the step rather than a constant, so both shrink together. That matters because the same pad can come up twice in a row, and two flashes that ran into one another would be indistinguishable from one long one. A test asserts the bound rather than trusting the arithmetic.

Playing without the clock

The Timed switch turns the per-press deadline off entirely. It is not a difficulty setting so much as an accessibility one: a hard clock on every press excludes players whose input is slower for reasons that have nothing to do with whether they remember the pattern. With it off, the playback still speeds up — that is the pattern being shown to you, not a demand on your reaction time — but you can take as long as you like to answer.

The best score is shared between the two. If that bothers you, the honest answer is that this is a single-player game whose score is stored in your own browser and sent nowhere, so there is nobody to be unfair to.

Switching tabs will not cost you a run

Browsers throttle timers and stop animation in a tab you are not looking at, so a run left running in the background would come back either mid-pattern or already over. Instead, the run pauses the moment the tab is hidden. When you come back, the round replays from the start — the only fair thing to do with a pattern that was interrupted halfway through.

Motion, sound and privacy

If your system asks for reduced motion, the pads stop scaling as they light and the colour change happens outright rather than easing. The pads still light, because that is the game rather than decoration; what goes away is the flourish around it.

Every sound is synthesised in the browser from oscillators — there are no audio files to download, nothing cached, and nothing to load before you can play. The mute button silences all of it, and the game is fully playable silent, since the colour and the shape carry the pattern on their own.

Everything runs on your device. Your best score and your two switches are saved in your own browser, nothing is uploaded, there are no accounts or leaderboards, and the whole thing works offline once the page has loaded.

Where the game comes from

This is the mechanic of Simon, the electronic toy designed by Ralph Baer and Howard J. Morrison and released by Milton Bradley in 1978 — itself built on the arcade cabinet Touch Me. The rules of a game are not something anyone owns, but a name and a look are: Simon is a Hasbro trademark, and neither the name nor the toy's red, green, blue and yellow quarter-circles appear here. What you get is the mechanic, in this site's own colours and shapes.