A tunable sound transmission device for transmitting an engine rumble sound into an interior of a motor vehicle includes a transmission line having a first end in acoustic communication with an air intake tract of an engine. A flexible membrane is positioned to sealably close off a portion of the transmission line thereby dividing the transmission line into two portions that are airflow isolated from each other. A receptacle is arranged at the second end of the transmission line and a user changeable sound characterization device is replaceably installed into the receptacle. The sound characterization device is configured and adapted to provide an intended frequency dependent sound attenuation characteristic and an overall sound dampening level for the transmitted engine sound.