Every synthesizer has this tiny little knob labelled as “white noise” which on its own sounds like… ehm, well… noise. Not very appealing, not spectacular. But, believe it or not, there are so many cool things that you can create with white noise. In this article I want to share 10 ways how you can use it in sound design.
By the way: If you want to know how these examples sound like, just watch the video below!
What is white noise?
Let’s take a brief look at the definition of the term white noise: It is defined as a random signal which contains all frequencies at equal intensity. Scientifically, this is also referred to as a constant power spectral density. And there’s one more very interesting thing about white noise. Even though it has equal intensity at different frequencies, we perceive it as being sharp. It seems as there was much more high end than low end in there. But that’s an illusion! Speaking of which, let’s create some more illusions…
10 sounds generated with a white noise signal
Here’s a list of 10 sounds that can be created with white noise plus effects and processing. Let the show begin!
The first sound we want to create is rain. Therefore, create a white noise source as your basic signal to work with. Then, use a highcut filter and a strong lowcut filter to sculpt the frequency spectrum. I recommend using only a bit of resonance for the highcut filter. And here’s an extra tip: Try automating your cutoff frequency to change the intensity of the rain! The higher your cutoff frequency, the more water. Figuratively, of course…
We had rain. So, why not create a thunder storm?! For this sound, it’s important to take a look at the color knob within your white noise section. (Note: Not every synthesizer has this color knob.) You have to choose a dark color which can also be modulated by an LFO to achieve some randomness within your sound. Now, create a very strong highcut to get rid off all the high end. This leads to a dark rumbling sound which is exactly what we want to go for. Additionally, you can use distortion effects to make the sound even more growling. Delay and reverb can be used to make your sound wider.
Next, let’s create an appropriate lightning sound. Guess what: A thunderbolt does not make a sound. Nonetheless, we associate a typical sound with it because we heard it so many times in movies. You know what I mean? Yeah, that hiss sound. It can be created very easily with a white noise signal by using a percussive amplitude envelope and a filter envelope to modulate the color of the sound.
OK, well, I think I can’t deny it: I love to construct weather sounds! :) To synthetically design wind, take a white noise signal. Then, create a highcut with a very strong resonance to create a whistling sound. Lastly, draw in an automation for the cutoff frequency. This will bring your sound to live as it gives it a certain randomness.
No more bad weather. I swear. Let’s go to the beach and enjoy some piña colada. Doesn’t that sound like a good plan? I think we need some waves smoothly rushing. Use a strong lowcut filter and a high shelve filter to dampen the frequencies above 2kHz. Apply a tremolo to modulate the volume. Finally, use reverb and delay to give your sound a little more space.
The secret behind the sound of somebody spraing graffiti is a very strong highpass filter. Bring in a bit of resonance. Then, set your amplitude envelope according to the length which your sound should have.
A sweep is a sound which became famous in electronic dance music. It appears right before your break or drop to blend the different parts of your track together. As the name might suggest, a sweep sweeps up. Thus, you have to use a filter automation that brings in more and more high frequencies. In case you want your sweep to have a whistling character, you need to dial in some resonance.
This is the laser-like sound that we associate with somebody watching TV and moving from one program to another. You might also think of somebody turning his electronic device on and off. Have a look at your amplitude envelope and your filter envelope. This is where the magic happens! Your sound needs to be short and snappy which means: short decay. Use very much resonance and a filter envelope with short settings.
Ambience is the technical term for the background noise which defines the certain characteristic of a room. Of course, this sound can also be generated with the white noise signal of a synthesizer. Filter everything except the midbass range of your frequency spectrum. Then, choose a convolution reverb with a preset that fits to the room which you want to simulate.
The last sound I want to show you is the helicopter. Let me reveal the magic trick: Just put a very fast LFO (sine wave) on your cutoff frequency.
You can create many sounds with white noise as your basic signal. This can be very handy in situations where recording real sounds is no option. For instance, you want to record rain, but the sun is shining. Or maybe you’re on a budget or you just have no time to organise recording equipment. It’s likely that you search on platforms like Freesound.org. But, if you can’t find what you are looking for, bear in mind: There’s this tiny little knob. For any other person, emulating real sounds is magic. For me as a sound designer, it’s my daily bread.