Making a Plasma Gun from a Beer Can

Designing sounds for really large or complex objects can be really intimidating especially for younger sound designers and those with limited access to sound libraries. I’ll be showing you how I go about breaking down complex sounds into simple little sounds that we can easily access with household objects, and then we will build our complex sound using these techniques. This is definitely not the quickest or most practical way to design sounds but it can really help when you get stuck or want to come up with some more creative ideas. It’s also just fun to push sounds really far.

 

Let’s Build Something 

Rather than try to explain my approach in a void, it’ll be much easier if I just go ahead and make a sound using it and I’ll explain myself as we go along.

First thing we need is something to design! I’ll be doing a re-design of the BFG from Doom (2016). For the purposes of this demo we are going to entirely focus on the gun’s mechanical and shooting sounds and ignore everything else. I’ll be doing all of the sound design with a beer can as source. This is of course wildly impractical but we can get a really interesting base to our sound that we may have never considered otherwise by limiting ourselves to only one object. Just to be completely clear, all of the sounds in the video were put there by me for practice and study and I have no involvement with the original sound design for Doom (2016).

 

BREAK IT DOWN Part 1 – The BFG

I like to approach breaking down sounds in two main steps. The first is finding all the “literal” parts; making sure what I’m designing actually matches the visual and I’m covering all the important details. The second is finding the “emotion” and/or “world-building” parts to make sure my sound fits in the world and has the appropriate emotional undertones.

 

Literally

Here’s a couple screenshots of the BFG where I’ve highlighted some areas I think are worth focusing on for our “literal” analysis, I’ll go into more detail on each below the images.

1. There’s some varied mechanical parts and some electric/plasma energy sparking around. There’s small latches mixed with larger pieces and they look like they could be made by a mix of metal and some plastic-like materials.
2. Here there’s some sort of core energy source with large mechanical parts with a lot of movement. This seems to be the main place where plasma flows through the weapon and steam is released.
3. Maybe some smaller mechanical and lighter movements here even though there isn’t anything obvious. Adding some sweeteners like stuff clicking into place or small vibrations. You can also see some reflections of some additional plasma containing parts on the central cylinder. I may add some additional plasma like elements to complement the larger movements.

4. Large gaseous plasma energy charging up. Air with electric and energy elements, some squelchy gooey stuff as well. Definitely want to have a cool down variation with some heat steam sounds after the shot.
5. Opening and exposing of energy core. Mostly just a continuation of part two but more focus on how the core may be outputting the energy, maybe add additional mechanical layers or some rotating metal type sounds to emphasize this.

 

With Feeling

There are a lot of more emotion/world-building descriptions we could use for this gun but I’ve chosen a few I want to focus on and some sonic qualities I think will do a good job of expressing them:

BIG F**KING GUN (the name): Big beefy low end, needs to feel powerful.

Experimental new technology: Instability in the sound, randomly modulated pitch and volume.

Violent and powerful: Aggressive metal movement, distortion, maybe low vocal-like elements.

 

BREAK IT DOWN Part 2 – The Beer Can

(or soda can if you are < 21 ?)

 To really emphasize this idea of breaking down sounds, lets try and design our BFG using only a beer can for source.

Now the question is what sounds we can get out of our beer can?

Here’s a list of some I thought of before recording:

• Tonal and metallic elements: Hitting the can with the tab closed
• Hard hits and steam releases: Opening the can
• Plastic-like and small mechanical sounds: Crumpling the can
• Plasma sounds: Slurping the beer
• Additional steam and electric sounds: Poured beer fizzing
• Aggressive metal movement: Ripping the can apart
• Larger mechanical sounds, low metallic elements: Flicking torn pieces of the can

This list isn’t necessarily guaranteeing that I’m going to use the sounds just like that but it’s just so I have a bit of a game plan before I start recording.

 

Time to RECORD!

For the recording I’m using a Rode NTG3 plugged into an Apollo Twin MKII. The pop filter is there mostly to protect the microphone from any splashing. I have a little bit of a plan going into the recording but mostly I’m just experimenting to see what cool sounds I can get out of it!

In this video I compiled all the sounds I ended up using in the final design:

After recording I went through and edited out the parts I liked and exported those out for later use. I always recommend doing that during these types of experiments! I ended up basically doing what I expected but a couple things didn’t turn out how I expected.

First, a disappointment: tearing up the can didn’t sound very metallic at all and wasn’t very exciting, but that might also be because I didn’t tear it hard or fast enough.

Second, a delight: The proximity effect when I flicked the large loose piece of the can up close to the mic produced some really nice low end that will be really useful for adding some beef to the mechanical layers and the shot.

 

Lets get DESIGNING!

When trying to do really aggressive designing like this, I accept I’m going to need a lot of tracks. To keep things organized in Reaper I set up my sounds into three groups: Mechanics and movement layers, charge and release, and the actual shot. All of these groups are then summed into their own busses so I can apply some buss processing to help glue things together and add some extra effects to everything.

Group 1: Mechanics and Movement

Even though this layer is the least extreme of the three, it ends up being the most challenging one and the one that took me the longest to design. It also is the one where the unique qualities of my beer can recordings can shine through the most.

The mechanical parts have to still sound like a real object and I can’t just process the sounds like crazy because at that point it’ll just sound synthesized (which works for the other stuff!). I need to keep as much of the organic qualities of the beer can as possible but also transform the sound enough that you don’t know right away what I used for my source.

Here are the mechanical layers soloed:

The sounds I ended up using the most was that of flicking the torn piece of the beer can in front of the mic, the combination of the heavy low end and prominent metallic textures worked really well at making the gun feel large and heavy. I sweetened a lot of the final clicks in the movements with the tonal closed-can flick layer (the first one in the recording video) that I pitched up to have a nice metallic high end.

Making things sound less like a can

First thing I’ll do is try and remove some of the mid range resonances that give away that what I’m using is hollow and can-like. This is a pretty straightforward process of EQ-ing out some of the peaks that aren’t adding metallic qualities. This almost always ends up being very mid ranged focused.

The next big part of transforming the sound is fixing it after pitch shifting. One of the biggest challenges when doing very aggressive time and pitch shifting with sounds it you often end up with lots of artifacts and unbalanced spectral content, especially when pitching downward, which is what I was mostly doing in this case. Even if you record at really high sample rates you end up losing a lot of high end when pitching down, making things seem much more artificial and lo-fi. There’s a lot of solutions for getting around this but I’ll share the one I primarily used in this project.

I’ll use formant shifting on the sound to pitch it up, mix it in with the dry signal, and then apply light distortion at the end to help blend them together a little more. After that I’ll use a little EQ to even out any weird places that started poking out with the formant shifting. I prefer this over the equivalent using pitch shifting, because it usually produces less obvious tonal artifacts. I’ll do this same thing for adding low end to a sound I pitched upwards, just formant shift down instead. If I want to add even more low end after that I’ll usually turn to a bass enhancement plug-in like Wave’s Renaissance Bass.

Steam and Plasma

The steam sounds were a combination of the simple air release when first cracking open the can and a super distorted version of the fizzing sound. Basically I just distorted the fizz until it became a harsher noise, then EQ’d out all the low-end and added a little digital reverb to even it out a bit.

The plasma/wet stuff is where things get a little more interesting. I used the sound of me slurping the beer but I ran it through iZotope’s RX De-crackle and set it to “output crackle only”. I’ve found this is a really good way to get the squelchy wet qualities out of a water sound while removing all the noisy bits. I’ll usually slightly pitch down that output as well.

 

Group 2: Charge and Release

This part is the most fun and experimental, as it’s all very extreme design and I get to go crazy with the manipulation without too much worry of going too far compared to the other groups. It will take ages to go through every bit of processing I did to get to what I ended up with but I’ll highlight some of the more significant processing I used.

Here are the charge and release layers soloed:

I focused on designing a blend of plasma energy textures, synth textures, and aggressive tonal noise/steam.

Plasma

Since I already went over how I designed plasma textures earlier I’ll not repeat myself but I’ll add that for the charge up and cool down I added some pitch modulation that raised the pitch leading into the shot and lowered it after. I also got some additional squelchy wet sounds by running some of the random mechanical sounds I made earlier through the modulation plug-in Mondo Mod, which I had set with a very high pitch modulation range and speed.

Synth Textures

I ended up using the same source for almost every bit of the charge up and cool down. I used the tonal beer can flick sound, which I then reversed and time-stretched. For the more synth textures I used a very tight and aggressive peak EQ which I then modulated up and down to go along with the movement on screen, ending up with a “pew” kind of sound. To make it a little more interesting I added some distortion after the EQ so it doesn’t end up sounding exactly like a sine sweep. I got some additional tonal textures by messing around with iZotope RX De-noise and using it super aggressively so I got a lot of interesting artifacts. I used it one of the crumpling sounds and used a very different crumpling sound as my noise reference. I would push the noise reduction very high and set the artifact control all the way to musical noise.

Aggressive Noise

The aggressive noise I just went crazy with. It’s several instances of FabFilter Saturn stacked on top of each other with the warm tape and heavy saturation settings and parameters on the plug-in randomly modulated all over the place. I would run several passes of my randomized Saturn patches until I got some textures I felt happy with and then shaped the dynamics and pitch to better go along with the visual. I also added some formant filters to try and give the noise a bit of a vocal quality and make the gun feel more like a monster.

 

Group 3: The Shot

As far as my processing goes, this group isn’t really doing anything very different from the other ones. I went with a pretty standard impact design approach, designing low, mid, and high frequency layers.

The source was most of the transient heavy stuff I recorded like the can opening, me smacking the can, and a couple of the different flicks. I also wanted to have a very aggressive “pew” with more transient blended in with the impact so I just stole the “pew” from the charge group, time compressed it, and adjusted the volume envelope. Most of the punch is being enhanced by bus processing, using a SPL Transient Designer and FabFilter Pro-MB. There is also some distortion and limiting at the end to make things just a little more aggressive. The bass is mostly coming from a very pitched down version of the can popping open and the smacking of the can against my hand with Wave’s Renaissance Bass.

 

Put it all together

There’s one final buss where everything sums together where I add just a little bit more processing to even things out. At this point its very nitpick-y mastering type stuff like a little EQ here and there, some limiting to bring up the level and maybe a tiny bit more distortion because everyone loves distortion.

To sell the sound a little better I added some reverb and a super basic ambience that did not come from the beer can. As I wanted to really focus on the gun itself I did not add anything for the explosion in the end.

Hopefully this will give you some cool ideas on how you can really push sound design to extremes and help you understand my strange obsession with using beer cans as source.

If you want to try your hand at designing some sounds with my beer can recordings I attached all of the sounds I used here! Beer Can Magic.zip