An air cleaner includes a housing having first and second opposite ends. A media pack is preferably oriented within the interior volume of the housing. In preferred embodiments, the media pack will have a first and second opposite flow face and be constructed and arranged for air to flow into the media pack through the first flow face, and for air to exit the media pack through the second flow face. The air cleaner will include a seal member forming a seal between the media pack and the housing. In preferred constructions, a secondary filter element is oriented within the interior volume of the housing. In some preferred embodiments, the housing is constructed and arranged as a resonator. Certain embodiments include a seal construction that engages the secondary filter element. Methods of filtering systems, servicing filtration systems, and constructing filter arrangements and housings will use filter elements and constructions as characterized above.