A soft start device for compressed air systems comprises a primary inlet at which compressed air at a primary pressure may be supplied, the primary inlet being connected with a secondary outlet able to be coupled with a load, by a valve circuit, at which compressed air is taken at the secondary pressure lower than or equal to the primary pressure, a principal valve placed between the primary and secondary outlet, said principal valve being able to be shunted by a bypass, a choke device being placed in the bypass, the principal valve and the choke device together with further valves of the valve circuit being connected together in a circuit and the valve circuit placed in a standard venting switching setting that the secondary outlet is vented.