The important part is:

271. In addition where

.a premise license or club premise certificate authorises the provision of music entertainment,

The entertainment permission has to have been applied for and in place first. In venues where none is in place - no form of live music that is for the purpose of entertaining an audience, can take place.

This is from the government guide to the Act and seems to me to be quite clear. Any premises, including those with a capacity of more than 200, could presumably write the provision of amplified/unamplified music into their operating schedule. Perhaps the author's are unreconstructed traddies determined to pull the plug on singer-guitarists !!!

They could but if they have not - these venues will have to pay again and go through the whole licensing process - just to enable non amplified music. I suggest that this very unlikely to happen?

But this section at least (and the Morris dance exemption) does for the first time make a distinction in licensing law for non amplified music.