Thanks all for the input. Regarding the noise my layout makes, I have a pretty good idea of what it is.
When I built my shelf layout a couple of years ago, I opted to use MDF instead of plywood. My shelf is 9 feet above the ground so safety was of course, at the forefront of the design process and the MDF is less likely to warp (which would cause derailments etc..).
The track I decided to use for my layout was Atlas (solid rail). IMHO, their track was the "quietest" out there and it looks really nice too. But when I installed the track, I opted to screw the track down for stability and safety purposes. I knew that when I did this, the screws would essentially transmit the vibrations straight down to the MDF boards. This is probably the primary source of the noise being generated.
I did use a layer of Woodland Scenics O scale track roll underneath to help dampen the noise. But, as noted above, the screws obviously go right through that into the MDF and thus, negate the noise dampening benefit of it.
I could try to loosen the screws a bit. If I do this, they may not carry as much vibration down to the MDF. But even then, I believe that the 3 rail track in general is just louder.
Some other notes about my preferences:
* I typically run my trains at 60 to 70 scale MPH. I know this is pretty fast, but I don't get any enjoyment out of them running at 5 scale MPH, so slowing them down isn't really a practical option for me.
* I also run around 15 to 20 pieces of rolling stock. I know, I can reduce that number, but again, I wouldn't find that enjoyable.
* Currently, my shelf layout is just a single loop with 0-72 curves. If I made the switch, I could substitute with 36r curves or maybe even 42r curves. I can't see myself running anything O on curves smaller than that. I just don't like the way it looks with the tighter curves.
And again, thanks all for the input/advice.
