Hi there newbie here , this has possibly been asked before but I was wondering people’s opinions on the quietest drone, straight out of the box withouy any modifications ?
Thanks
Most of the DJI mini series of drones are really quiet.
Look at @ianinlondon youtube channel he does sound comparisons of most if not all of the DJI series of drones.
https://youtube.com/@ianinlondon
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… one not flying? 
look for the sub 250g mini drones, probably those with 2x props per motor, once they are up and say 30m away they are quiet
anything dji mini, think the quietest one is the mini 3 / mini 3 pro… you can also get other propellers that may lower the pitch somewhat but they can get pricey for a minimal / marginal benefit
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Hahaha interesting thanks for that nice you can swap out the propellers , still doing researching contemplating buying a DJI drone in the spring. I’m in South East London so slightly put off by the lack of places to fly freely.
As has been said, once the drone is aloft and any more than a few yards away from you, the noise is not a problem, and once you get to 20 or so yards you can’t hear it (well, I can’t against the normal city background noise, but my hearing is not what it was). The Squeeze, though, hates me flying it indoors because the whirlywhizz props and the noise frightens her. Even with the propguards on, she is freaked by the noise. I think it’s not just the volume, but the pitch plays a part as well.
I’m told that the DJI Neo, being smaller and with smaller props, is louder and higher-pitched & whiny, and some people find it annoying; never heard one but I suspect I wouldn’t like it much! In order to generate lift, the props have to run faster, so the motor noise and tha prop noise is different.
There is no method that I know of of generating the sort of lift we need quietly; propellers spinning at high speeds are noisy, ye canna change the laws of physics, Jim! Those bladeless Dyson fans would do it, but the doughnut coil that makes them go is pretty heavy, so no good on any sort of aircraft.
The upcoming Flip will be interesting in this respect (as well as several others) in that it will have enclosed props which, it looks from the pictures, are single piece double bladers unlike the flippyflappy single piece single blades we are used to on minis. The ‘bicycle wheel spoke’ bracing for the integral prop guards must have an adverse effect on performance, which will be reduced both in terms of lift produced and motor efficiency, and probably will have a different noist to the Minis as well. Presumably performance is not catastrophically affected by this, but I wonder if the motors are more powerful/faster and the props have to produce more lift to compensate for the extra weight, wind resistance, and compromised prop-blade aerodynamics…
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Noise is different to many people.
You will often hear your drone even at a high level as you know it is there.
However others may not hear it at 50 feet because they are unaware of it.
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yes you will find that smaller drones run much higher kv motors than bigger drones which will run lower kv motors.
the kv of a motor times the battery voltage will give you the (no load) rpm of the motors… smaller drones tend to run lower voltage batteries, where as bigger drones will run higher voltage batteries.
the other consideration is prop speed … actually it’s blade tip speed, a smaller prop can run faster than a bigger prop because as the prop gets bigger, it’s blade tip speed gets faster, and you need to keep it below supersonic (speed of sound) speeds because at these speeds, the airflow around the prop becomes unstable and the prop will no longer be cutting through the air and pushing the air but creating an air pocket void so it will provide less lift or air volume movement
the other thing to take into consideration is to some extent vapour pressure around the propeller as the prop has to provide more lift from a thinner or narrower or less number of blades prop the air around the prop (normally at the tips first, then trailing edge) ends up with the air having a lower vapour pressure, this means that air around this region has more chance of having ice form as the vapour pressure of the air is lower and therefore the dewpoint rises from what the dewpoint is within stable air at ambient air temperature… hence there are advantages to having a prop with more blades, larger in size and spinning slower
with regards to noise of the prop, I believe it relates to the smoothness of the prop, and the shape of the tip so that the airflow is less likely to reach supersonic speeds of the airflow around this region during to the air pressure… lower air pressure… lower speed of sound / greater chance for air speed (blade / tip speed) to be operating in the supersonic region and less likely for noise to be heard as the airflow enters this unstable region.
this is where master airscrew propellers come in, they can be extremely smooth and sharp on the trailing edge.
a prop that’s stiff also won’t deform when the airflow over it pulls the prop or trailing edge in a certain direction because of air pressure, hence I suspect that the rubber tips on the mini 3 pro props allow for the tips to deform depending upon the air pressure at the tip and thereof less likely to enter this critical pressure region around the speed of sound.
here is an interesting design done for a propeller driven aircraft designed to achieve mach1, and the props were designed to achieve mach1 when the aircraft did, not before, short propeller with an altered blade profile to the tips dont exceeded Mach 1 / speed of sound early … bit like an egg beater, probably not very efficient at lower speeds (or rather able to accelerate quickly at low speed)
obviously was not taken forward other than the test bed aircraft
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@Jakenbad76 The simple answer is DJI mini4 pro! 
There are aftermarket props that claim to be stealth but not worth it IMHO.
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Each one gets quieter with every revision
Remember DJI’s first attempt at a smaller drone, the spark, that was one angry sounding annoying bastard of a thing
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NOT the DJI Neo!
It is a fantastic drone, but quiet it ain’t!
(@ianinlondon has a good YT video about that)
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nothing is ever simple
mini 3 pro quieter before takeoff. (but who flies a drone sat in takeoff position)
during takeoff the same,
in the air about the same… 
… call it the same
I fly around a lot of building sites and most of the time people are oblivious to the mini 3 pro… but I am normally at 40+ meters…
when I fly a 20m grid then people will notice it
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I had the mini 3 Pro, was quieter than my mini 2, but I still say the mini 4 Pro draws less attention. 
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I filmed a threeway today.
And in other news, I did a sound comparison test between the Neo, Flip and Mini 4 Pro… Editing that to get it out tomorrow or Monday, but as an unsurprising spoiler, the Mini 4 Pro is way quiter than than the neo and Flip. But I was surprised that the Flip is about the same as the Neo both near and even 80 metres away… I thought the Neo would be the loudest by far…
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I’m unsure if this is the right sort forum for those type of videos. 
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If it’s good enough for youtube, it’s good enough for here… 
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@Kirky What were you doing today 
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Wayne 
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Right all… afore mentioned 3-way is now up…
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