Why?
I live in a mid-terraced house and as much as I’m loving my new table it’s way noisier than my old CFTBL due to thinner cabinet panels and metal (backbox) panels. These create/allow more of the mechanical noise from the solenoids and balls to escape. And there are more solenoids, multi-balls and manic action to make noise. As much as I enjoy this I need to consider the neighbours.

Result/benefits?
I was aiming to reduce mechanical noise (not speaker audio) and this was achieved, but not to a point where it dulled the gameplay enjoyment. It has taken a lot of the harshness and clatter out of the overall sound whilst leaving the deeper thuds. So I was happy with this but there was an unexpected benefit that the whole machine now felt as though it was of a much more solid and improved build quality all round. It really does feel like a superior machine.
So even if you don’t need to bother about noise you may want to consider trying this.

General Notes-
I applied this to my new Stern but I’m pretty sure the principle will apply to other machines. If any manufacturers read this they should consider trialling this and maybe offering it as an option for home users, as it really does feel better, sound better and would be simple to install during the build process.

I’ve done the best I could but there may be materials better suited to this than I have used. I couldn’t find any information about doing this sort of thing. I emailed Stern who kindly replied but said they had no idea about soundproofing a pin! Likewise from the soundproofing manufacturers. I ended up using some Silent Coat 2mm Damping Mat and Absorber 15mm ‘egg box’ foam after watching the simple demo below and then finding the materials relatively cheap on eBay - £60 in total. However I now think that the Damping Mat does not work as well on wood, or that I should have chosen a thicker version? If anyone knows better please comment below. Also I was unsure of how much space there would be for the foam and again you could probably go with the 30mm if you wanted.

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Method-

Removing The Playfield: I lifted the playfield into the usual upright position and uncoiled the wiring loom and loosely tied the bundles together. Unfortunately some of the cables appeared to have connectors up in the backbox so I couldn’t easily completely disconnect the loom. Correct me if I’m wrong here, but if so it would be so much nicer if manufacturers could make the loom easily disconnectable from within the cabinet. I then got a friend to help me lift the playfield out using the secure parts circled in red and rested the front legs on the coffee table and the rear on a camera tripod. A little precarious but it did the job.
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OT But Cool: First job was to install the PinGraffix decal blades that had been waiting for 6 weeks for me to get round to removing the playfield. An excellent addition.
http://pinside.com/pinball/forum/topic/%E2%80%A2star-trek-le-pinblades-first-glimpse%E2%80%A2
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Applying Damping Mat: This is bitumen(?) backed foil that comes with wax paper over the bitumen. It doesn’t need to cover the whole surface, see video link above, so I cut it into reasonable pieces for the most easily accessible areas of cabinet. The bitumen just sticks to the wood. I also stuck some in the backbox below the mobo's.
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Applying Absorber Foam: This is glue backed foam, very sticky. I cut this to go over the Damping Mat to hide it and help secure it, plus I wanted to cover more area with the foam. I was a bit lazy and covered the easily accessible areas. If you took more time you could unscrew some of the wiring fixings and cover more cabinet. Take care not to cover up the ventilation holes, circled in red. I wasn’t quite sure how far up the cabinet I could go without it catching on the playfield or wiring so I used the line of just below the support rail, which seemed to be about right as you can see from the last internal pic, underlined in red in both pics.
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Replacing The Playfield: Needs to be done slowly and carefully if possible, especially with the blades in place, I managed to nick mine I would suggest lowering in at an angle to the side and then twisting it round once below the top? Anyway, lower it onto the support rails and slide back as normal.

Then enjoy playing a plusher sounding pin

I've posted this because I couldn't find any information on the subject.
Hope this is of some use or interest, cheers Mark

Thanks

I downloaded a db meter for my mobile phone to try this but on reading up on these types of meters it seems they're pretty limited due to the mic properties in phones. I looked at hiring a proper db meter for the day but the cost was way too much. All I can say is that there is a definite reduction in volume, mainly at the higher end of the spectrum, which means a lot of the 'rattling' sounds were dampened.

Re: fire retardant, I was looking into this while searching for products, but now I've re-visited the Silent Coat pages I notice they don't mention this, so I've emailed them the question. The foam in the installation isn't actually touching anything that may get hot but it's worth bearing in mind with other machines. Some other foam makers were definitely quoting the highest flame retardant ratings, so maybe shop around for products?

P.S. as much as I love fireworks I don't intend to be adding them to my pin, though I wouldn't put it past some of the Metallica owners

Ok, finally got round to trying this on a spare piece. After holding four matches to it it caught fire but the flame dwindled and went out on it's own. I emailed the distributors about the rating and they said they got no response from the manufacturers despite several requests. So it appears to be flame retardant but I don't know about an official rating.

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