I've just listened to the Clash's debut LP, I'm now listening to the Buzzcocks debut, yesterday I listened to some Damned, some Undertones, some Clash and some Magazine, (all on vinyl, most of it original, and because i've had to do an essay on it). Why does some of it, the Clash's debut especially, sound so dated, while some of it - like the Buzzcocks debut - still sound fresh today? The production? The songwriting? The basic sound of it?