Mid Wales Opera undertake their OpenStages productions with a positively missionary zeal, nurturing both their local communities and up-and-coming singing talent. So full marks – if not the full five stars – to them for this staging of Purcell’s Dido and Aeneas, realised remarkably over a single intensive week of work. Given the way the composer tailored his 1689 opera for the ladies of Josias Priest’s boarding school in Chelsea, it was an entirely appropriate choice. A motley crew of amateurs formed a chorus variously portraying Carthaginian courtiers, followers of a witches’ coven and sailors. Well-schooled in the characteristic physical gestures and movements, with singing similarly ranging from lusty roistering to sadly sober, they gave it their all. The greater vocal polish came from the young cast, some already launched on singing careers, all handled with the utmost care by conductor Jonathan Lyness, notably in his accompaniment to their recitatives. Director Richard Studer was also the designer of the starkly simple but highly effective set: against a backdrop at the west end of the cathedral, …