This is a sound that is actually very easy to make, but many people seem to struggle making it. The Flume sound that I'm talking about is at 3:20 in Some Minds
https://youtu.be/IfLqsNRkBIo?t=3m20s-------------------------------------------------------------------------
Method 1:
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Make some white noise, and cut off all frequencies below ~350 Hz (change this depending on how much noise you want). Then make a basic sine wave and put it on a low note so that it makes a sub bass. Then put a bitcrusher on the sub bass, and downsample the sound a bit. Then cut off all of the audible low frequencies, so you are just left with the high pitched noise. The sub bass is only there as a carrier for the high pitched downsample noise (there is probably a better way to do this).
Layer these two sounds together and you have the first way to make the Flume sound.
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Method 2:
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For the second method I used a Fruity Free Filter, and some white noise. First get the white noise and put a filter on it. Make this a high pass filter, and turn up the Q (or equivalent knob) very high, but not quite at the max. Next bring the Frequency of the high pass filter up to around 8000-16000, the only difference here is the pitch that you want.
Personally I prefer the first method more, as you can adjust the individual white noise and the high pitched noise separately. If you have any better ways to do this, I would love to know.