Unless you're a music journalist, the likelihood is that you have a music age. This is the era that the overwhelming majority of the CDs in your collection date from, often harking back to your early clubbing days. For me, this is the mid-Nineties, the time of Britpop and Cool Britannia, Noel and Liam, Damon and Alex, when my friends and I unleashed ourselves on the clubbing scene for the first time.