Originally Posted by JoePro
The colder the cleaner, my friend. This applies to the entire spectrum.
This simply ins't the case. With hefe yeasts, and all other yeasts, the colder you ferment you can still cause stress on the yeast and cause undesirable or desirable off flavors or esters. This is an advanced technique that is used when brewing hefes (to ferment cold to stress teh yeast out).
Too hot or too cold stresses the yeast. clean ferments are typically the result of steady middle of the road temps. i.e. for ales 68F constant for the entire ferment.
for most of your pale ales, IPAs browns, stouts porters I would try to hold 68F for ferment. For hefes, lambics, lagers and belgians those are different animals.
Belgians in particular have odd yeast strains. I made a belgium quad recently and kept the ferment temp at 83F for 5 days - worked fantastic and no crazy smells or undesirable esters. Try that with a cream ale or other and you might get some funky tasting brew.