Why are keyboards, mice designed to make sound when pressed and clicked?

Question

Why are PC keyboards designed to be audible when they are pressed? That, IMHO, is a totally unnecessary thing as it generates noise that might disturb a peer who is studying nearby.

The other thing is mouse, which makes a lot more noise than a keyboard when clicked. Especially when people are playing games. The noise of these devices are too disturbing that I sold my laptop as I struggled to use it at library without disturbing someone.

In short here are my questions. I think are related:

1. Laptop keyboards are mostly noiseless. Why are PC keyboards not designed that way?
2. All mouses that I know have the disturbing 'click-click' sound, is that not possible to avoid?
3. Why is the the on-board mouse (the one below the touch pad) on most laptops noisy?

I'd appreciate any explanation that might justify the status quo. I reckon that there are some laptops with less noise. For example, my friend's Macbook Pro doesn't make much noise when the on-board mouse is clicked. But in majority of the laptops, that is not the case.

P.S- This question is about hardware user interface, and I hope it is on topic.

Answer 1

To begin with, not all keyboards and mice are designed to make a sound - some are designed for exactly the opposite, for obvious reasons.

But to answer your question, there are 3 reasons, and the third one is by far the most important one.

(I came across this topic while drifting off researching the mechanism of electric piano keyboard; the following is correct to the best of my knowledge.)

Contact

When two parts are touching, sound is produced.

Cost

It is possible to reduce the click sound by the likes of rubber, but this means some extra cost (applied much more in the past than in present days).

Firing Feedback - to reduce wear and fatigue.

If I remember correctly, nearly all keyboards fire with less than 50% of the max pressure being applied (note that pressure is different from excursion - the relationship between the two is not linear). When no firing feedback is provided, users tend to apply extra pressure, which in turn increases wear and fatigue (depending on the key design, and there are many, wear can be in the springs, relays, sensors, or rubber).

Non-firing sounds

Perhaps one exception to this is keyboard like the flat Mac ones - if you try them, you'll see that most of the sound is generated when resting the finger on the key, but none or hardly any sound is produced with firing. It is perfectly possible to make typing sound on these without typing anything, and once your finger is on the key, it is possible to type as much as you like with no sound.

The keyboard is design to apply counter pressure (to prevent false triggering) but once a pressure threshold is reached the key gives up, which provide the firing feedback.

Answer 2

Because the people designing noisy keyboards are optimising for a different UX goal to you.

Some keyboards are designed to be low noise. Using rubber domes under the keys to detect keypresses. Meanwhile other keyboards are designed to provide maximum feedback to the typist.

These use a variety of mechanisms for feedback, including backpressure, activation force changes and keypress sound.

Arguably the most popular keyboard ever created, the IBM model M, features loud clacking sounds as one of its major UX features, and some serious typists will keep hold of one of these keyboards for decades, because their UX has been perfectly optimised for typing.

tl;dr: Keyboards optimised for not being annoying at work are quiet and feature low feedback, but keyboards optimised for maximum typing speed provide as much feedback as possible and that includes deliberately loud key noise.

Answer 3

It's for feedback to the user. Without feedback of some sort, the user has no way of knowing the entry was accepted by the system except visually. In some cases, people still 'touch type' their entry and, without an audio feedback, they would be forced to look at the screen.

Answer 4

One possible answer is to understand the user's internal goal in a workspace. One of the goal is to show he is working. For instance, while writing this answer I'm sitting in my cube typing the words of the answer. It makes a lot of noise which makes me look like I'm working hard on something. If my keyboard didn't make any noise, then my cube will be very quite and it may appear I'm not doing anything.

This answer may sound "funny" but you always need to dig in and find the user's internal goals (look busy). Making a noise, is one way of achieving this goal.

Therefore, for the most part, users will dislike a quiet input device and prefer a noisier one (with in limits).

In Alan cooper's about face, he explains better than me about internal user goals and how the system (input device in this case) should help the user achieve this goal