Dealing with some stepper driver adjustments I noticed a lot of high frequency vibrations on the x carriage. The heat sink fans add some vibrations but by them selves and lowering the speed a little I could learn to live with it. But when I fire up the radial nozzle fans 100% there is actually a lot of vibration. I do not know what this would do to the print quality but I bet it would give me a rougher finish. Anyways, none of these fans are very well balanced. So, is everyone using the stock fans? Kind of annoying they run at 24V. Makes finding replacements more difficult.
I just stuck a 100ohm resistor in series with my hotend fan and it takes the edge of it noise and vibration whilst in no way compromising the job that it is there to do. The fact that it's run at 100% is just a consequence of the fact that its on a circuit with no controller!
Did you mean that you lowered the speed of the heat sink fans? I thought these fans which come on at 40oC are fixed speed? "The heat sink fans add some vibrations but by them selves and lowering the speed a little I could learn to live with it" Posts elsewhere (e.g. from Greg) do say that the print cooling fans are a little "aggressive" s3d provides infinite control over the print cooling fan speed and for PLA I use max 60% and at lot of people use zero fans for ABS.