The Thermaltake New Soprano VO900 case is designed to support either air or liquid cooling (or a combination of the two). 

(Courtesy of Thermaltake)

For air cooling the New Soprano comes with two Thermaltake labeled fans installed; one 200mm Blue LED fan in the front and one 120mm fan in the back.

Front 200mm Blue LED Intake Fan (600~800 rpm)

Rear 120mm Exhaust fan (1000 rpm)

The following table lists the noise generated by the two included case fans while operating at different speeds with the side panels on and the front door closed.  Sound Pressure Levels were taken 3’ from the front of the Soprano enclosure.  The ambient background noise level was approximately 26 dBA.

With both fans running at full speed the noise is noticeable but not loud and provided good airflow through the case.  Slowing the fans down by reducing the voltage still keeps air flowing but makes the case virtually silent.