During the production of filter cigarettes (10), these are subjected to testing with the aid of test air. For this purpose, air is introduced into the filter cigarette (10) at one end. The air emerging at the opposite end is measured. The filter cigarette (10) is subdivided into testing sections or testing chambers (22, 23) for the purpose of more accurate testing and in order to derive more accurate information, in particular for testing a tobacco stick (11), on the one hand, and a filter (12), on the other hand. The testing chambers (22, 23), which are sealed off from one another, are connected to separate sensors.