What does summer sound like to you? Maybe it’s the pock pock pock of tennis, the buzz buzz buzz of a wasp or the pat pat pat of heavily-applied suncream. For me, it’s the sounds of corks popping, sandwiches being unwrapped and singers doing their vocal exercises. By that I mean the season of opera festivals that signal the beginning of British summer time. I’m going to talk about four different opera picnic combo options: Opera Holland Park, Grange Park Opera, Big Screen Opera and firstly, Glyndebourne.