This is not a good practice to do. Covering can frighten some birds, it may not prevent the chattering and noise, and it is not fair to them to keep them covered and isolated since they are flock birds and enjoy the company of people as well as other birds.
Some owners cover birds at night so they have darkness and can sleep. I see nothing wrong with covering to adjust light cycles, but as a noise control, I don’t agree with the practice.
