Make your pinball machine more silent

Pinball machines make a lot of noise. Electronic pinball machines have sound effects. That volume you can adjust. But mechanical parts like coils make a lot of noise too, which you cannot change !

Especially if you live in a large building this can be very annoying for your neighbors, and restrict you to play pinball only during the daytime..

Luckily there are some things you can do to make a pinball machine a bit more silent. Most of these changes will have an effect on the level of sound heard in other rooms btw. In the same room you'll still hear a lot, as it's impossible to make a machine totally silent. And the less background noise there is, the more pinball sounds you'll hear, up to the pinball which rolls over the playfield..

The obvious first: make sure the playfield glass is on the machine and the coin door is closed too. Especially the playfield glass will already stop a lot of the volume.

Adjust sound effects
Electro-mechanical pinball machines usually have a bell or chimes. Disconnect them, or put something between the moving parts so they make less noise.
Electronic sounds can be adjusted by a volume control. Most games have a pot for this (usually on the left side inside the cabinet). On WPC games you adjust the volume using the switches at the inside of the coin door. They do have a minimum level, on default settings you cannot put the volume lower than 8. In the adjustment menu you can set 'Override min. volume' to 'Yes', then the game allows you to set the volume lower, all the way down to 0.

Knockers. Pinball machines have a 'knocker'. This is a coil which shoots a plunger against the side of the cabinet to make a big sound, when i.e. you have a high score. Its goal is to attract attention so people in a pub notice you're a good player.
On most games this is a coil which is located in the cabinet or near the edge of the backbox. Disconnect the coil if there's a connector, cut/desolder a wire (make sure it doesn't short against anything else) or put something between it so the plunger makes less noise.
On WPC-95 games the knocker isn't installed anymore but the sound is played through the speakers, on these games you can adjust the knocker volume in the settings.

Next step: a lot of the sound travels through the metal pinball legs to the floor. Especially in older houses with wooden floors this is a big issue. To stop a lot of this sound, put some padding underneath each leg.
You can buy nice rubber cups in which leg levelers fit, they're cheap (around $6 for 4). However these rubber cups make the machine stick to the floor, so it's very difficult to nudge it. If you like to shake a machine whilst playing, you can put something underneath these rubber cups so the machine slides again..

If you really need to dampen the sound that your neighbours hear a lot, then you have to pay more attention to the contact sound. The rubber cups underneath the legs won't be enough as the rubber used is quite hard. It will be necessary to add more layers between the legs and floor to dampen every vibration. You can use pieces of carpet, or a good solution is to use some cork.

rockwool cabinet

Too many decibels coming out of your game ?

Add some noise-protection inside the cabinet then. I used Rockwool insulation because I had it available, but there's specific sound-reducing insulation you can also buy in DIY shops.

Be careful and stay away from the transformer !! (not only so you won't short it, but also because it gets warm)

And if you also use something like Rockwool which has one metal side, be sure to put this DOWN, so when i.e. a wire from a coil comes loose and hangs down, it cannot short anything !
Trivia question: do you know from which machine the cabinet in the picture is ??

In extreme cases you must go a lot further. Some people have even put small pieces of rubber onto every coilstop, to dampen the sound of each coil. So yes, in theory it is possible to make a pinball machine very silent. But this requires a lot of effort so will only be done if it's really the only way you'll be able to enjoy your machine..