Thanks Vapor!
Any comments on San Ace H1011 undervolting?
The dream fan is something that you can keep low to daily use and crank it up when you need. The San Ace H1011 goes to 90CFM that is really good, if it can keep it quiet as a YL D12SL-12 when needed it should be a winner.
I bought the YL D12 high speed trying to achieve that.