Unless one lived in London in the 18th and early 19th CC one had 
little, if any, opportunity to hear the work of the European masters: 
except only chamber music, and even then only in a few places -- 
chiefly cathedral cities -- where there was a critical mass of 
competent musicians. Though the infant Mozart visited London and was 
well received by Christian Bach (the leading European musician in 
England at that time) I should be very surprised if his later 
compositions were much performed or even known outside London until 
long after his death. To be sure, everyone had heard of  'Mr 
Handel'.  The nobility knew his operas, and many had heard of Messiah 
and some of his other oratarios. But here too, there were few other 
places in the UK other than Dublin where they were performed. 
Correspondence in the archives of Sidney Sussex College between John 
Hey (c.1760) and his sister tell of a rare, once-in-a-lifetime trip 
to Bedford (I think) to hear Messiah. Haydn's concerts in London in 
the 1790s were a resounding success, but I don't think he went 
anywhere else except to Oxford, where he got an honorary degree.

As for Adam Smith, he preferred to live in Edinburgh, a musical 
desert because of the absence at that time of an Anglican cathedral. 
He probably did hear the work of contemporary French composers with 
his friends Quesnay & Co. in Paris. But we can guess his opinion of 
such un-Presbyterian flummery from the contemptuous treatment of all 
artistic folk in his account of 'unproductive labour': where they are 
unfavourably contrasted with churchmen, statesmen -- and 
'philosophers' like himself. I believe that the first economist we 
know of who was said to like music was (rather surprisingly) James Mill.

Anthony Waterman