What Makes a Switch Clacky
Clack is high, sharp and slightly ringing. It is a deliberate design outcome, not a fault, and two specification lines tell you whether a switch has it.
Clack is bright, sharp and immediate, with a faint ring after the note. It is the sound most people describe as “loud typing”, and for a decade the hobby treated it as the thing to engineer away.
That has reversed. A great many of the switches released in the last few years are built to be clacky on purpose, and the two things that cause it are printed on the listing.
Worth separating from the start: clacky here is a sound, and it is not the same as a clicky switch. Clicky means a mechanism that makes a deliberate click, a jacket or a bar, and it applies to the feel as well. A linear switch with no click mechanism at all can be extremely clacky.
1. A hard housing, which rings
Sound comes from the stem striking the housing twice per press, once at the bottom and once on the return.
Polycarbonate is hard and brittle. It transmits the impact rather than absorbing it, and it rings slightly afterwards, which is where the brightness comes from. POK and LCP, which appear on newer switches, are harder again and brighter again.
Nylon does the opposite: it absorbs, it deadens, the note stops. That is thock.
A polycarbonate top over a nylon bottom, which is very common, gives you a bright upstroke and a deep downstroke. Half clacky, deliberately.
2. A long pole, which is the bigger factor
This is the one that changed the hobby.
A long pole stem is extended so it meets the bottom housing earlier, cutting total travel from about 4 mm to 3.5 mm or less. Two things follow. The stem is still moving fast when it lands, and it lands on a smaller area. The result is a hard, sharp, high bottom-out, much louder than the same switch would be at full travel.
So total travel is the fastest read on this page. A switch listing 3.5 mm or 3.4 mm is telling you, without using the word, that it is built to be sharp. One listing 4.0 mm is not.
That single number distinguishes most of the current generation from most of the previous one.
3. The board, which can override the switch entirely
A hard plate amplifies all of this. Brass and steel are bright and rigid; polycarbonate and FR4 are dull and soft. A rigid mount transmits more to the case than a gasket mount does, and an empty case rings where a foam-filled one does not.
Which cuts both ways, and is worth knowing before spending money: a gasket-mounted board full of foam will mute a clacky switch considerably. If you bought long-pole switches for the sound and they arrived sounding flat, the board is the reason, not the switches.
Whether you want this
Two honest points.
Clack carries. It is the character people mean when they say a mechanical keyboard is loud, and a long-pole switch in a brass-plated case is genuinely disruptive in a shared room. If that is your situation, the answer is silent switches, which remove the impacts entirely, or a nylon full-travel switch in a soft board.
And clack is fatiguing for some people in a way thock is not, because the energy sits in a higher frequency band. Nobody can tell you in advance which camp you are in. That is what a switch tester is for.
What to look for
- Housing: polycarbonate, POK or LCP, ideally on both halves.
- Total travel: 3.6 mm or less, which almost always means a long pole.
- Not silent. The pads remove exactly the impacts you are trying to hear.
- A firm plate and a rigid mount, if the board is still to be chosen.
The rest of the vocabulary
Thocky is the other end of the same two variables. Creamy is a separate axis about smoothness, so a switch can be creamy and clacky at once. Every figure referred to here is on the entries in the index.