Quote Originally Posted by Macca View Post
I discovered some years back that just closing the curtain on the window behind me was the equivalent of an entire system upgrade.

Really no exaggeration and that's just a curtain (albeit a quite thick thermal one).

Prior to that I always wondered why my system sounded better in the winter (when it was dark when I got in so curtain closed all the time).

This is why I am always saying you don't need to use expensive and possibly low WAF 'dedicated treatments' to get big gains.
Agreed!