Editing Damping

[[File:Damping.jpg|250px|thumb|Various damping techniques]]

'''Damping''' refers to reducing the noise made by a keyboard. There are two points within each keystroke that are inherently noisy: [[bottom out|bottoming out]] (pressing the key all the way down until it comes to a stop, with the sound being the so-called "[[clack]]") and when a released key comes to a hard stop in its home position.

Keystrokes can be damped either by using [[keyswitch]]es with internal damping, or by designing or modifying the keyboard to cut down on sound.

==Damped key switches==
<div class="rellink">Listed in [[:Category:Damped switches|Damped switches]]</div>

===Prongs===
Progs project laterally across the width of the slider.

<gallery widths=250 heights=187>
File:Logitech Romer-G -- slider.jpg                 | One "elastic touch piece" from a [[Logitech Romer-G]] switch
</gallery>

===Vertical dampers===
The [[Alps SKCM Cream Damped]] and [[Alps SKCM White Damped|White Damped]] switches achieves damping by way of small rubber dampers fitted into channels on either side of the [[slider]]. The new [[Matias switch|Matias quiet switch]] resurrected this idea. With Alps and Matias switches, the rubber blocks are removable, allowing damped switches to be converted to undamped switches; with the "silent" version of [[Cherry MX]], the rubber damper is moulded into the slider and cannot be removed.

<gallery widths=250 heights=187>
File:Damped sliders.jpg                             | Damped [[Matias switch|Matias]] and [[Alps SKCM Cream Damped]] sliders
File:Cherry MX slider -- damped.jpg                 | "Silent" [[Cherry MX]] slider designs, with upstroke and downstroke damping using a moulded-in rubber damper
File:Cherry MX slider -- damped vs non-damped.jpg   | Classic undamped vs damped Cherry MX sliders
File:Cherry MX slider -- damped vs non-damped 2.jpg | Classic undamped vs damped Cherry MX sliders
</gallery>

===Vertical rings===
Vertical rings placed on either side of the slider. This is used in the [[i-Rocks switch]].

===Horizontal rings and mats===
Rubber rings can be placed around laterally around the slider in a manner similar to vertical rings. They can also be placed around the base of the nub that holds the return spring.

<gallery widths=250 heights=187>
File:Omron B2R-M -- slider, front.jpg | Separate upstroke and downstroke rings around an [[Omron B2R series]] slider
File:ASM MEXICO reed -- opened.jpg    | Landing mat on a [[Clare-Pendar S88010 E9]] switch
File:RAFI RS 76 C 010 -- angled.jpg   | Landing ring on a [[RAFI RS 76 C]] non-illuminated switch

</gallery>
===Rubber domes===
[[Rubber dome]]s are inherently quiet when bottomed out, as the impact sound is absorbed by the rubber.

==External modding==
===O-rings===
Small rubber '''O-rings''' can be fitted around a key stem to cushion the impact of bottoming out: Instead of the slider reaching its bottom, the O-ring hits the switch housing.

The effect of using O-rings is a distinctly cushioned landing when bottoming out, when the O-ring makes contact with the switch housing around the slider. The resulting reduced travel (related to the diameter of the O-ring's cross section) and feel is similar to typing on some scissor switch keyboards.

On [[Cherry MX]] and [[:Category:Clones of Cherry MX switches|clones]], O-rings are fitted inside keycap stems against the internal struts in the keycap.
Keycaps without internal supports around the stem are not suitable.
The O-ring must be pushed some distance up into the keycap, otherwise it completely impedes slider motion.

The thickness of the O-ring should match the keycap used, or it will impede key travel (and feel) too much or not cushion at all.

[[OEM profile]] keycaps are typically used with thicker silicone O-rings. [[WASD Keyboards]] rate their own O-rings as follows:<ref>WASD Keyboards — [http://www.wasdkeyboards.com/index.php/cherry-mx-rubber-switch-dampeners.html Cherry MX Rubber O-Ring Switch Dampeners (125pcs)]</ref>

{| class="wikitable"
! Part number !! Hardness !! Travel reduction
|-
|| 40A-R || 40A || 0.4mm
|-
|| 40A-L || 40A || 0.2mm
|}

Cherry-profile is more often used with orthodontic bands: very thin O-rings originally intended for dental braces. The size to get is ''3/16" Medium''.

<gallery widths=250 heights=187>
File:O-rings.jpg|O-rings
File:O-rings fitted.jpg|O-rings fitted to keycaps
</gallery>

===Soft-landing pads===
'''Soft-landing pads''' are small square pads of rubbery material placed over the top of a switch. The work the same as O-rings except that they are not tight around the key stem.
<gallery widths=250 heights=187>
File:Soft-landing pads.jpg|Soft-landing pads
File:Soft-landing pads fitted.jpg|Soft-landing pads placed onto [[Cherry MX]] switches
</gallery>

===Silencing clips===
A silencing clip works like a soft-landing pad by muting the bottom of the stroke but they also dampen the slider's return. They clip over pre-existing switches.
Compatibility with keyboards on the market is very limited.

* [[UNIQEY]]'s '''QMX-clip'''. Two variants exist: The original variant is only for [[Switch mount#PCB mount|PCB-mounted]] [[Cherry MX]] switches. A second variant for [[Switch mount#Plate mount|plate-mounted]] switches got introduced later.
* [[Zeal PC]]'s '''Zealencio''' silencing clips. For both plate-mounted and PCB-mounted [[Cherry MX]] and [[Gateron KS-3 series|clones from Gateron]] that have compatible housings including [[Zealio|Zeal PC's own switches]].

Like with O-rings and soft-landing pads, bottoming out is cushioned against internal struts in the keycap which requires that the keycap has them.
Both QMX-clips and Zealencios are made for [[Cherry profile]] keycaps and would need an additional O-ring for use with OEM profile.

Plate-mounted clips do not fit together with [[Stabiliser#Costar | Costar-style stabilisers]].

Because QMX-clips and Zealencios surround the tops of Cherry MX switches, thick-walled keycaps work with these clips should be mounted only on key switches with the LED window facing towards the user or else the clip's plastic wall would be in the way and greatly reduce key travel.
This means that they are unsuitable together with thick keycaps on many keyboards, including almost all keyboards made for [[backlighting]] as those typically have the switches oriented with the LED window facing the other way.

The clips also don't work with clicky [[Cherry MX Blue]] or [[Cherry MX Green|Green]] because those have small pins in the base of the slider that would get in the way. Clicky clones from Greetech also has those sprues but [[Gateron KS-3 series|Gateron]] does not.

<gallery widths=250 heights=187>
File:QMX Clip and Zealencio.jpg|QMX Clips (left) and Zealencio clips (right)
</gallery>

==Internal modding==
===Topre O-rings===
A regular [[Topre switch]] can be turned into effectively a ''Silenced Topre'' switch by placing a thin ring of cushioning material around the slider inside the housing.

One such aftermarket product are the ''Hypersphere rings''
<ref name="dthypersphere">Deskthority thread: [https://deskthority.net/help-f53/silencing-rings-for-topre-rf-or-hhkb-t10051.html Help:Interest Check: Silencing Rings for Topre RF or HHKB]</ref>.
Other brands are DESKEYS and Silence-X.

==="Trampoline mod"===
The bottom of the slider inside a [[Cherry MX]] switch is a pin that plunges into a tube. The "trampoline mod" involves opening up a switch and placing a small piece of rubber inside the bottom of that tube.

The [https://geekhack.org/index.php?topic=50632.0 original mod] used a section cut from an O-ring but silicone balls have been sold especially for this purpose.
Clicky Cherry MX switches have different sliders from other variants, requiring different lengths (or number of balls). The mod can be difficult to reverse.

[https://worldwide.espacenet.com/publicationDetails/biblio?FT=D&CC=DE&NR=3742711A1 German patent 3742711], filed by [[Sasse]] in 1987, describes this and other approaches and depicts them as applied to [[Sasse series 25]] as well as their taller switches.

===Latex mod===
A small amount of liquid latex "milk" can sometimes be brushed on the inside top of switch housing switch to dampen the sound of the slider's return.  This is often discouraged because latex being a natural material is susceptible to spoiling after a time. Latex is especially sensitive to oils - which could be in [[lubrication|lubricants]].

An improved mod is to use silicone RTV gasket maker ([https://scarff.id.au/blog/2020/silenced-kailh-speed-copper-switches/ instructions], [https://www.reddit.com/r/MechanicalKeyboards/comments/cm1mll/new_silence_and_trampoline_mod/ original]).  The silicone is resistant to the oils in typical lubricants.

===Lubrication===
Coiled springs can in some instances be lubricated to reduce [[ping|reverberation]].
Too much lube on a spring could interfere with the switch's operation and electrical contacts must never be lubricated.

For [[buckling spring]] switches, the dental floss mod would be more suitable as it is more easily reversed. 

===Dental floss mod===
{{Main|Dental floss mod}}

Reverberation of [[buckling spring]] switches can be reduced by placing a piece of dental floss inside the coiled spring. If done right, it should leave only the sound of the click.

==Keyboard construction==
===PCB mounting===
[[Switch mount#Plate mount|Plate-mount]] keyboards hold the switches firm, and effectively amplify the sound of keystrokes. [[Switch mount#PCB mount|PCB-mount]] keyboards cut down on the sound by flexing, thereby absorbing the impact of keystrokes.

Some PCB-mounted keyboards can be further damped by placing rubber drawer liner underneath the printed circuit board.

===Damped plate===
Sound can also be damped with careful construction of a the switch-mounting [[Switch mount#Plate mount|plate]], and its mounting.

A ''gasket mount'' keyboard has rubber gaskets sandwiched in-between the plate and case top and bottom.
A mod for [[Custom Keyboard Construction#Tray Mount|tray-mounted]] keyboards for achieving a similar effect is to mount rubber O-rings on the standoffs that the keyboard "sandwich" is mounted to.

Some plates have slits cut to allow them to flex.

Brass and wood are known to have lower-pitched and thus more pleasing noise profile than materials such as aluminium and steel.

===Weight and solidness===
Many custom keyboard cases are made from thick solid metal, often with brass weights for extra weight.

Some modders have modded plastic cases by mounting reinforcing ribs at weak spots, that would otherwise vibrate.
Some modders have even put lead weights in the bottom.

===Sound-absorbing material===
Sound can transfer and reverb inside the voids of a keyboard case. Modders often fill such voids with sound-absorbing materials.
Most often, various kinds of foam or rubber are put at the bottom, and (if possible) in-between plate and PCB.

Soft materials have ranged from PE foam (packing foam) and EVA foam (craft foam, gym mats etc.) to Sorbotane.

Bitumen sheets have sometimes been placed in the bottom of keyboards, both to add weight and for its vibration-damping properties.

==Other==
===Cushioning under the keyboard===
Hard plastic feet on a hard desk surface will amplify the sound of key strokes.
Soft rubber feet underneath the keyboard prevents that.

If a keyboard does not have soft feet, the keyboard could be placed onto an extra wide mouse pad or desk pad that would provide some cushioning.

===Damped keycap===
NuPhy's '''GhostBar''' is a two-part [[Space bar]] with a sound-absorber of silicone in-between the key stem and the main keycap.
<ref name="ghostbar">NuPhy store—[https://nuphy.com/products/ghostbar GhostBar]. Retrieved 2023-08-08</ref>

==References==
<references />

[[Category:Keyboard terms]]
[[Category:Guides]]
[[Category:Keyboard modding]]