Water Wall Sound Water walls can be set up to sound whisper quiet through to a moderate sound of running water in a room having low background noise.  To make the waterfall quieter, fill the bottom tank so that the bottom edge of the stone or glass back panel just touches the water when the water wall is running.  To increase the water wall sound reduce the level so that the water falls further from the bottom edge of the back panel to the actual water surface in the bottom tank. Our water wall video's include soundtracks.  To watch video's, and to listen to water wall sounds, click here. Pump Noise To create the most relaxing ambiance possible it is desirable to hear the gently running water, but not to hear the pumping mechanism running the water wall.  Great care has been taken when selecting and mounting pumps for our water walls to achieve the quietest running system we can, resulting in pump noise that is inaudible even in a quiet room. As sound travels much further and is attenuated far less in water than in air we do not use submersible pumps.  By far the easiest (and cheapest pumps) to use are submersible, but we found we could just not achieve the extremely quiet pump noise we were looking for.  Because of this we use multiple expensive water cooled (eliminates fan noise) pumps to achieve the required flow and desired lack of pump noise.  We have tried pumps from virtually every manufacturer selling pumps in the USA.  Incidentally, just about every other wall fountain available in the USA uses submersible water pumps to reduce price. Furthermore, commercial applications typically have a pump room area where the pump may be mounted remotely.  We can make our commercial applications with pumps mounted locally removing this requirement/expense and still achieve inaudible pump noise.