Another week, another online concert; and since orchestral music seems likely to be confined to screens and stereos for a while longer, one might as well try and experience something new. But not too new — I’ve pretty much had it up to here with the present. The Hallé orchestra is currently streaming a collection of Shropshire Lad songs by George Butterworth, conducted by Sir Mark Elder and sung by the baritone Roderick Williams in orchestral versions of his own creation.