You do not mention which model Amel you have.
I'm not sure how loud they are but being a classic transformer and a big one the 50/60 hum could be quite annoying. Putting them against a wooden wall could make it a giant loudspeaker so to say.
Apart from that you may want to consider the heat coming off the transformer. They need sufficient airflow. Also they are quite heavy so you need to mount them quite sturdy.
I once put a similar isolation transformer in a boat (in a locker) and the sound in the adjacent cabin was clearly audible. Luckily nobody had to sleep there.