Here is my system for uncoupling, I have 27 on my small 22" x 13' layout, one at each position that I would want to spot a car at or break a train at. 

Moderator note: Changed to embedded YouTube video.

I've been ballasting track and have noticed an (expected) increase in the noise a train makes when traveling upon it.  My layout is topped with 2" foam, has cork roadbed, and WS ballast affixed with diluted white glue.  I'd say that the sound difference between my unballasted and ballasted track is about 30% louder after ballasting.  Much has been shared about noise levels on this site and a search using the box in the upper right will return many postings.

Hi all

I will post all my progress of my track build in this Blog from start to finish as I go.

So I have decided on my layout design and as per previous posts I have 3 of the Modules built. I have now started to lay the foam base for the scenery and track work will begin soon. I will use a foam roadbed for the first time in place of cork, a local manufacturer has a very good product that I will use. they have 3mm single roadbed with a chamfered edge and is split down the middle and they also do a 300mm X 450mm square that I will use in the yards etc.

Hi again

Well I think I have what I'm looking for, gone for a much simpler design and yet still getting all the operations I want from the layout design

Here are a few pictures, I'm still not sure about the yard, comments welcome on this.

Here is Module A, the Coal Mine, I could add more but I think I will add trucks and equipment rather than more track. I may move the fuel track closer to the building so the hill can be closer and have more scenery impact with trees to match the backdrop.