Noctua redux and industrialPPC Fan Round-Up @ Bigbruin.com
 

With the addition of these two new product lines, Noctua now offers a much more comprehensive line up of cooling fans. They have something more like a budget-friendly / entry-level option with the redux line, they still offer their "standard" fans which are considered some of the best fans on the market, and they have the industrialPPC line which offers high end features for energy-efficient / low noise operation even in harsher conditions.

http://bigbruin.com/content/noctua-fans_1