The simple songs such as come on you reds or cider army can get the whole ground going. The more complicated ones are much more difficult to keep in unison or just people don't know the words. This isn't unique to city. Southampton, for example, can be a very quiet ground but saints go marching in can be very loud, reverberating around the stadium. I have noticed the away fans react to the rest of the south stand much more than section 82 as they hardly hear them.