So I get 12,000 ad impressions and like 4,000 page impressions. But Adsense pays in page impressions and not ad impressions?
The last sentence the one that asks "But Adsense pays in page impressions and not ad impressions?" or is it something wrong I have set up with my channels?
Yes, that is correct. Google AdSense is only going to pay per page-load. So it does not matter how many ad views there are, but rather the number of pageviews on your ad blocks. So I would not recommend loading up your pages with multiple ad-blocks just as an attempt to get more ad views. Focus on quality instead. Hope that helps.