This might sound like a very stupid question, but here it is... Is it actually necessary to connect the box itself to ground? Does it help in shielding/reducing noise? Or is it just a convenient way of connecting the in and out jack sleeves?
I ask because I have some of those plastic enclosed sockets which I might use on an enclosure which will have in and out on the back and was thinking about simply connecting the pins as it looks like it's been done in this
image.
Reason I ask is because I've always assumed it would work just fine as long as the ground keeps running down the chain through the jacks but am now wondering whether "using" the enclosure might actually be useful? Either way it would serve as a Faraday cage and help isolate from radio interferences, but is there more to it? I'm inclined to think not, but please do correct me if I'm wrong..!