Something Old, Something new

I've been working on my new choral setting of Isaiah chapter 6 (the piece is still without a name) and started to realised that parts are starting to sound a bit like The Testament of Dr. Cranmer. I'm not quite half way through the Isaiah piece and its the sort of time when all sorts of doubts occur and you can become convinced that you are writting complete drivel. All you can do is continue and then revise later, in the clear light of day. So I'm going to assume that this is another aspect of this problem and now worry too much about pieces sounding alike. After all, I can hardly create a brand new sound world for each piece, can I?????