Lufthansa b747 vs a340 comfort

It depends. For economy, the layout for the 747 is usually 3-4-3 while in the airbus A340 it is typically 2-4-2. In the rear end of the b747 though, there are several seats that are 2-4-2 configuration.Seat pitch varies with airlines. But airbuses and 777s tend to have a slightly wider seat which makews quite a difference. 747s seem to have the narrowest seat width.

I just flew Lufthansa from Chicago Frankfurt on airbus 340-it is a wonderful aircraft-without a doubt, better than the Boeing 747

I find them pretty much to be similar...but some say the A340 is quiet. It also would depend on how much the load is on your flight