Just want to share my personal experience. I got the No Crow collar, we have a decent size Easter Egger roo,and he could still crow pretty loud with it, I tried adjusting, we got two sizes to make sure, etc... Neighbors complained, we can't have roos to begin with. I was about to list him on craigslist but decided to try the baby sock trick, I cut an OldNavy 12-24m sock, folded it 3 times and wrestled RockyDoodle, got the thing around his neck, he crowed and it was very muffled, but still crowing louder than "hen noise level".
I decided to cut the other sock, and this one I rolled like a ring, and pushed it down, right below the folded sock. He tried to crow : SILENCE. Not a sound. I made sure it wasn't on too tight, that he could still eat and drink normally, and do his rooster thing with the hens. He can still make normal chicken sounds, but absolutely NO crowing. A week now and it's going great, the other morning the "collars" had shifted a bit so he let out one or two crows, pretty low ones, and we readjusted them to the "silent" position.
It's working great so far. He stands tall and "crows" but no sound comes out, and he's still a satisfied and happy, sweet little Cockster.
Radhanuga, did you use just the tube part of the sock and not the foot, right? About how tall was the 3x folded one (how much of the neck did it cover)? And where on the neck did you place the socks? I have a Cream Legbar that the rooster collar is not working on. I'm going to try your method and see if it works better. I had success with one of these collars on a Silkie roo. Ended up rehoming him anyway but for a different reason.