Not all systems are required to be silent but yet require maximum airflow.  As usual CCI likes to provide the professional market with the maximum number of relevant and important choices when it comes to cooling products.  CCI began serving the residential space where noise was absolutely critical and the 'formula' was 50/50, fans had to be effective, yet quiet.  If you failed at one, the product failed, very simple.  Mainly it's commercial applications that are different except this background works well when it comes to conference rooms, work areas...

So very simply put, many products are available with High Velocity fans which means the products can move a lot more air but are typically much louder.  There is no magic fan that can move crazy amounts of air while still being silent, it is again just somewhat of  a formula of primarily fan rpm's and then other factors come into play like fan size, fan blade design...  Some believe larger fans are quieter but that's not really fact.  The basis of this is that larger fans can be set to spin slower but then still move more air than a smaller fan.

Are High Velocity Fans better quality?  We run into this often where some do believe that just because it spins faster and moves more air that it is better 'quality' but a big factor in defining quality is the application.  If you are installing products in a home theater, a 'quality' product has to be silent.  If installing fan units in a server room, 'quality' will usually involve that the fans move significant amounts of air with noise not being much of a consideration at all.  For this reason, do not simply order High Velocity fans due to a perception of better quality.  In reality CCI's normal fans provide for aggressive cooling at the higher rpm range (running on max/12V).