Ok I feel like I have read all the threads and I have a gate on my main valve but still can’t get this thing what most would consider quiet. Any help would be greatly appreciated. Sorry for the last pic, I was just showing I have a gate valve on the primary siphon.
I always have the opening of the siphon around 6 cm below the water surface - this is how I have done my two pipe drain - 100% silent if you adjust the flow with the gate valve so the water level hit the edge of the emergency drain - but not go over - it will be silent.
you don’t need elbows on the siphon for a Bean setup. But you do need the opening to the siphon to be a few inches below the height if the water in the overflow.