The dimming function works flawlessly and significantly better than in the energy-saving bulb before. The dimmable range (light / dark) is wirkich very large. The LED bulb has (for a passive illumination) so much power that I operate mostly close to the lower limit. To illuminate a room it would of course not enough.
Aaaber:
Once you dims even just a little, the bulb begins to hum penetrant. As I sit about 1 meter next to the lamp that bothers often enormous. Once the TV is on it goes, but softly may not be the scene ...
All in all a great LED bulb with some restrictions on the volume. Who does not bother who gets a top quality product.
I do not send the bulb back, but will try another next time.