They are sleek, bright, have no lag when turned on at 100%, dim evenly across the range and appear to be of high quality. % hum a little louder. Even at 99% or 1% they hum. I tested 3/6 of the ECUs and they all buzzed about the same. The sound is about as loud as that of a large fly and can be heard up to 15 feet away outdoors. .The noise comes from the electronics box, so theoretically you could isolate it a bit to muffle it. However, I don't want to imagine how 6 of these will sound behind drywall. The dimmer used is a standard triac. Dimmer (TP-Link Kasa HS220). These dimmers didn't buzz when dimming about 8 other brand LED bulbs so I'm pretty sure it's not a dimmer. I really like this design/brand but I will only buy bulbs that don't need to be dimmed. "Basic" version - same size, same design. The differences are a lot less hum, a little brighter, dimming to a lower level, nuts instead of clamps.
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