How to Create Rock Monster Sound Effects

13th August 201919th June 2023 | by JJ Lyon

Tyler Hoffman is a sound designer and musician currently working at Yessian Music as an audio engineer. His passion is to create sound effects for video games and film.

As a long-time Krotos user, he’s given us some insights in to how he’s used Krotos plugins in his sound design work.

Tyler Hoffman website

Tyler Hoffman on Using Krotos Dehumaniser 2 & Reformer Pro to design Colosse, the giant rock creature.

I discovered Krotos back in 2016 while working on a sound design project for school. I owned no sound libraries and my universities libraries had no creature sounds I could manipulate to my liking. While looking up how creature vocalizations were created in The Desolation of Smaug film, there was an A Sound Effect article interviewing David Farmer. While the article doesn’t specifically call out Dehumaniser, at the bottom of the page was a “Creature sound design – further reading & resources” section. Dehumaniser (the first version) was listed as a resource. I was ecstatic to find such a tool existed that I could use my own voice or other sounds to turn into creature vocals

I downloaded a trial and shortly purchased Dehumaniser, and I was able to easily convolute my own voice with pig, alligator, cats, and dog sounds to yield some pretty crazy results in a matter of seconds. Dehumaniser 2 saved me an immense amount of time.

Giant Rock Creature Vocalisation with Dehumaniser 2

A couple of years later, while working on my first 360 video to learn the FB360 tools for ambisonic audio, I needed to create vocalizations for this giant elemental rock creature. This creature, Colosse, emotes a small range of different emotional states. These emotional states would be a neutral state, an aware/worried state, and a dying state. In the video, you are in a fixed position for two different scenes watching this nomadic human character interact with nature. From behind, you start to hear footsteps and our creatures first vocalization. There’s no back story so your imagination is free to determine if our small character is out to hunt this monster or just observe and study it.

This video is available in its original form on the Oculus Store and Steam for free. I reached out to the director of the video, Nick Pittom of the publishing company Fire Panda LTD if I could get a high res version to work on and he gave me permission to use and post my final product.

To correctly utilize Dehumaniser 2, the trick is all in the name. You start with a human vocal performance of some sort and dehumanize it! I didn’t like my performances of roars, so I recruited my dad to go in my closet and roar into a microphone and give me some different types of emotions.

Afterwards, I started experimenting with Dehumaniser’s presets. They weren’t fully helping me achieve the sound I wanted for this creature. I liked the convolution modules, but I felt like I could get a more customizable sound if I mixed an additional animal vocal in with Reformer Pro on a different track. There’s a learning curve for using Dehumaniser to just the right amount. It’s easy to get carried away with it and think the more modules you add the better a sound will be.

I made three different “Rock Creature” presets that I switch between. I mute or bypass different modules within the preset at times for different sonorities of the vocalizations since some of the modules affect certain harmonics.

Looking at my RockCreature01 patch, I will walk through the different modules I have and why I chose them.

The Noise Generator + Delay Pitch Shift module while used in series creates the initial “mask” for the creature. The Noise Generator distorts the audio, making it sound very aggressive, while the Delay Pitch Shift creates the size of our beast. It changes the decay of the produced voice, while creating a delayed loop of the input. Using these two modules in serial creates a convincing creature sound alone while just barely dipping into an overly computer-like sound.

In parallel runs a Granular module which I have creating a lower guttural layer. I didn’t change the default locations of the parameters too much. The reproduced grains of audio created a nice whispery hiss that I thought the overall sound required by playing with the Grain Pitch parameter. I left the Grain Size relatively small because I just wanted a hint of what the granular synth has to offer.

Lastly, I have in parallel a Pitch Shifting module to simply pitch the input signal down 2 octaves. I used this module to help create the size of the beast. This in conjunction with the Noise Gen and Delay Pitch Shifter worked wonders.

The EQs in Dehumaniser become your best friend in terms of cutting out some fun frequencies that start to make their way into the mix. They’re equipped with 5 bands with a gain tolerance of +/- 24dB to attenuate most of what you like or don’t like. With the whole patch working, in comparison with the clean audio, my dad now actually sounds scary.

Even with just Dehumaniser 2, my Dad has turned into some scary monster, but it does not sound like this magical rock titan in this video. Now I have sent my creature vocal through an Auxiliary channel for some additional processing to be thrown in beside it. The two plugins that really add some sounds are Reformer Pro, & Infected Mushroom’s Manipulator. I purchased the Krotos Rock Impact library to use with it. Slowing down the playback speed + playing with the mix added a nice rocky movement to the roar while Manipulator pitched it down and played with the harmonics slightly.

I used Reformer Pro a lot to supplement the design of Colosse’s movement sound. With each arm/leg/body movement, there were a multitude of concrete, brick, tree, earthquake, avalanche, and other sounds all meticulously placed to create and sound like movement. There was no real method to my madness; I wanted to try new things out and experiment. Eventually I ended up with a great sound. But even after all this processing, it was still missing an organic life-like layer.

The next step was to try to convey that this creature is a giant and has magical properties that makes it speak and move. I started auditioning different animal wails and bellows and I eventually landed on using alligators and walruses. Adding in these creatures among some others with additional Reformer rock impacts, I started getting super close to what I was looking for.

I still I wasn’t where I wanted to be! I was thinking of some references I could try to mimic. I thought of The Balrog from the Lord of the Rings and how there’s a gritty fire substance to its roar. I discovered layers of cinderblocks being dragged on a surface were recorded to help supplement its roar. Using this newfound knowledge, I recorded dragging bricks and cinderblocks on different surfaces and dropping rocks on cinderblocks. With some creative editing, EQ, Pro-Subharmonic, Lo-Air, and the Infected Mushroom Pusher I at long last found what I was looking for. The following sounds are some examples of what “Colosse” makes (without reverb/delay) in the video below. These sounds were mixed in an ambisonic space so they may sound a little different in stereo without processing.