We have chosen for active cooling in our toplights to enable the creation of compact stable products that will keep its properties in the best available way for many years ahead. Great power from compact/high density component areas, requires very efficient and responsive cooling technology to regulate the temperature. Some of the greatest factors here are:
Fig 1. Example of setup including airducts in simulation. The ducts also greatly allow decreases of temperature affect in closed environments.
Actively cooling of course, creates some noise though. If you experience the decibel level to loud, say if you are a minor grower, there is always the option to duct the airflow, which will decrease the decibel levels to some extent. Also, at lower light levels the (stepless) fans won't run as high and won't make as much noise.