Good luck with that lol. We had a little bantam rooster and he got the neighbours complaining to council and we had to get rid of him. They all make noise that will annoy neighbours and will crow day and night (once stayed at a bed and breakfast and their dam rooster was crowing at 2am)
You have a couple of options. A no crow collar. It gets mixed feedback. Some love it, some say it doesn't work. My parents neighbours use one and my parents didn't even know they had a rooster till recently so it worked for them. Do your research though as put on wrong it can be harmful to the rooster or not work. Sometimes despite constant adjusting they still don't work.
Your second option is only if the ordinance is only about night noise, it won't help during the day. Some people lock their roosters up in a soundproof cage or box in their garage at night. You need to make sure they won't overheat in summer in there and it has adequate ventilation too. By putting them away at night they muffle any noise they may make and reduce it to a degree as they don't seem to crow quite as much in the box. Guy we bought some of our chickens from had his right in the middle of the city with homes all around him but he was able to reduce the noise enough at night that nobody complained.
Good luck!