Okay, so I have a few more thoughts...lol shocking, I know (hahah)
They are individuals, but they have the same vocal potential within each particular species...Kind of like cars... A person can drive a Porsche at 25 MPH but if that person wanted to go 190+, they easily could (anyone with that same type of Porsche could easily do so, assuming nothing was wrong with the car). The same could not be said of someone driving a Smart Car, whose top speed is 84 mph. Now, 84 MPH is still fast, and can still get you a speeding ticket, but it's not even close to 190 mph...Does a Porsche have to go 190+ all the time? No....But would some people go that fast if it was legal? Sure!
My point is, unless you live with a bird for months, you will not have experienced its full "speed", AKA volume potential (and often, not even then due to all of the factors that can influence this-age being a huge one--and puberty happens later in "toos", so technically, if you get a baby, you are looking at YEARS before you get to meet their adult version).
Even if someone says they have a cockatoo that is quieter than average (which may still be loud--just quieter than other cockatoos they have met), there is no way to know what YOU would end up with (ESPECIALLY if you get a young one). You are guaranteed to have a bird with extreme volume capacity/potential/ability if you get a cockatoo (just like you are guaranteed a car that can go 190 mph + if you get a new Porsche)--- The frequency and volume of a specific "too" in a specific setting depends on a lot of factors, juts like the speed of a car depends in the personality and motivations of the driver (only unlike the speed of a car, a cockatoo's volume and intensity is much less of a conscious "choice" when compared to a foot on an accelerator).. The bottom line is that their noise potential is
not variable- every cockatoo (within its own species anyway) has the same potential to make the same, super loud noises as any other cockatoo within that same species--- unless there is something physically wrong from an anatomical perspective. M2s and U2s are know to be the loudest (at least in terms of potential noise/capacity), but other cockatoo species still are capable of producing extremely loud sounds when compared to other pet birds. Of course there is variation among daily noise patterns of individual birds within various settings...but it's the potential for noise that you must consider.
Loud noises are normal for them in the wild. They are programmed to be loud because it is how they communicate with their flocks... Now, is screaming constantly 24/hours a day normal in the wild? No...does it sometimes happen to birds with issues in captivity, yes. That having been said, a well- adjusted, happy, healthy cockatoo is almost always going to be loud at some point daily (often more than once) and sometimes for over an hour . If you do everything right, are a behavioral master, train your bird to be independent, set up a paradise and massive aviary, provide tons of enrichment etc,
you still are going to have a bird with the capacity for extreme noise. The bird may be quiet compared to some cockatoos, but I would venture to say that it could still be too loud for your son...far louder than a parakeet in terms of decibels..
Regardless of people's personal experiences, the general consensus and overwhelming majority of cockatoo owners describe their birds as loud (maybe not all day, but still, loud when the bird chooses to be)...but there are also a million in rescues all over the USA who were given up because of their screaming (it is one of the main reasons these birds are given up so often).
So if you find someone whose experience implies that their cockatoo is "quiet", they would be in the minority, which means it would be highly unlikely that your experience would mirror theirs. Also- "quiet" to them may not be "quiet" to you.
Additionally, birds before puberty are going to be quieter, so when asking about volume levels, it is also important to consider the bird's age.If noise didn't matter in your situation, I wouldn't be concerned, but it does.
Let's say you get a cockatoo and it is loud (cockatoo loud, not parakeet loud)....on a daily basis (which, frankly, is the norm according to many). What will you do? What will you do if it is causing extreme tension in your home and really upsetting your household? This is why I keep posting, because this is what matters.
^Remember- again, before I knew the details on your situation, I encouraged you to keep your last cockatoo---so it's not personal, but your circumstances are quite specific and they matter because these birds live forever and in your situation, a loud bird could cause serious problems (
you have acknowledged that certain types of noise would be a deal-breaker). I just don't want you to end up in a situation where you have an unhappy bird or an unhappy family and end up having to re-home in order to maintain sanity within your home..and it seems like a lot to gamble on, given your awareness of the possibility for extreme noise, in conjunction with your household's individual dynamics.
If there were a way for you to know with certainty that you adopted a quieter cockatoo, then that would be one thing, but there is no way of knowing that ahead of time.
There are so many variables that can influence cockatoo's vocalizations, including the presence of certain people, time of day, home size, presence of other birds, behavioral factors, individual personality, age etc. Plus, the same bird may be quiet in one setting and not in another.....In all cases, the POTENTIAL for extreme volume is there- so it's a massive risk to take on such a bird when you already know loud noises are problematic...The whole family will have to be supportive of this decision forever, and it could be difficult to maintain the level of support needed to care for a "too" if the noise creates new problems within your home.
If someone is a weak swimmer, I would advise that they not jump into a riptide in the ocean. If someone is allergic to bees, I would advise that they steer clear from apiaries...If someone cannot stand the sight of blood, I would urge them not to become a surgeon...Does a poor swimmer always drown in the ocean? No, Does a person with a bee allergy always get stung? No, Does a surgeon always have to look at blood? No, not always...BUT the fact is that in all of these scenarios, the likelihood or risk is very high.
If someone has noise sensitivities, I would urge them not to to get a pet cockatoo for the same reason. The risk is high---even if you hear from someone who says theirs is quiet, using that to justify getting one yourself (when you already know definitively that loud sounds do not work in your home) is a bit like like risking getting struck by lightening because you heard that people have survived it in the past.
If a noisy cockatoo would have to be re-homed, don't consider adopting one because the risk to the bird is not worth the benefit to you. It isn't fair to the bird to go into the relationship knowing that something common and natural could cause you to give him/her up and cause lasting damage to the bird as a result of relinquishment.. You can hope for the best but you must also be prepared to accept "the worst", especially when you already know that there are extenuating circumstances in your home. If you (or your son/partner etc) could not live with the worst-case-scenario for potentially the next 80+ years, then you should really consider whether this is an appropriate gamble, given the circumstances and cockatoos' natural tendencies toward noise.
Here is a link from a breeder/educational organization that discusses potential noise as well:
https://mtrushmorebirds.com/cockatoos-think-carefully-before-buying/
Also, behaviorally (and in terms of noise) Galahs are known for being the "easiest" cockatoos (no- they are not "easy" compared to many other birds..they are still cockatoos...) BUT what you said about them being too needy etc applies even more to the larger cockatoo species (who also happen to be louder as well)....Cockatoos are known for their "neediness" ..among other things... lol....So, I guess I am not sure what you could even consider at this point, because the "quietest" and least-needy option (while still needy compared to other birds) is likely a Galah (even though they can be quite shrill/loud still), and, as a rule, the bigger you go from there, the more amplified/intense all of the other behavioral traits become (volume, neediness, potential for neurotic tendencies etc)...Plus, you must consider that you already have multiple birds, and while a cockatoo could get along with them, it could also seriously harm them or become jealous etc. The cockatoo you had was not with you long enough for you to see how their behavior can change when they bond to a person,but they can get pretty obsessive and very demanding of time/attention etc...Additionally, they need a TON of time outside of their cages, and if you are trying to give your other birds time as well, you may run into issues if they cannot safely be out at the same time.