As an Information Architect I'd tell you users are there for the content and stay for the content, not the ads. They accept that ads pay for the sites they use, but dislike being forcibly interrupted or distracted during their use of a site.
The ad industry has resorted to larger and more shouty adverts, like those that @Chrys refers to in his answer, alongside more stealthy adverts that masquerade as content in order to fool the user and keep revenues up.
The end result is users are more suspicious and resentful of adverts, when this is combined with increased awareness of security issues users are simply less willing to click and increasingly frustrated with the page 'noise'.
So to answer your question, no, more ads may actually equal less revenue and less users (this is what @Lèsemajesté was using sarcasm to say).
The keys are:-
Keeping the ads to a minimum.
Ensuring their placement on the is well thought out - in the users eyeline but not too aggressive or distracting.
Quality of the content AND advert is good, and appropriate for your audience.
Basically users won't click ads that are annoying and there is no point advertising financial services on a cookery site unless it's a package to help chef's start a business for example.
I'd suggest taking a look at heatmap and eyetracking studies (Jakob Nielsen's 'F-Shape' is a good place to start) and give more consideration to the products your site advertises.