It does sound à bit when its set in wave..

excellent product, works just as well with the VorTech and cheaper price.

compact wave maker in less price . make good wave like tune wave box and vortech .

after owning tunze 6105 and getting wp40 i can say build quality is same or better.very impressive
altough rubbers on magnets are rather flimsy.
somehow its rather noisy when its set to any other program than constant speed.you can clearly hear it ramping up and down.however if powerhead is out from bracket its silent.so its vibrations from powerhead to glass that makes noise.
and i would say minimum size tank for wp40 is 4 ft.i have it in 3x2x2 and its a bit too strong.
flow is broad