A wet/dry vacuum cleaner having a cover closing off the upper end of the vacuum cleaner, a lid connected to the cover having a collector extending into the lid and a filter assembly extending downwardly from the collector into water tank, the lid having an exhaust port for the vacuum cleaner communicating with a exterior thereof.A volute is disposed internally of the lid and coupled to the exhaust port, the volute being generally horizontally mounted in the lid forming a flat volute for accumulating air flow.