GrowCNanswered grow question 2y ago I have several AC Infinity fans and I LOVE them! In North America they are AC Infinity but in Europe I think Mars Hydro has a very similar product but I have no experience with them. I have the digital controls so the fan will turn on/off as needed depending on temperature and humidity. And, they are the quietest fans I've ever used. I have no need for a silencer because it's such a quiet fan.
Any fan will be loud when working hard. Most of the noise is not from the fan but the air rushing through the duct/pipes. So, if you want quiet buy the next size larger fan and duct/pipe than you need and run it at 30-50% speed.