DIY Fart Sound Machine: Build Your Own

I have built more novelty noisemakers than any dignified adult should admit. The fart sound machine remains the crowd-pleaser, and it’s a better electronics project than it has any right to be. You can go fully analog and tune squeaks like a middle school brass section, or jump into microcontrollers and create a portable fart soundboard that sounds uncannily real. If you bring one to a family gathering, you’ll learn very quickly who secretly loves mischief.

Below you’ll find two complete builds, one mechanical and one digital, plus tips for making the sounds convincing instead of cartoonish. Along the way, I’ll answer the questions that always pop up: why bean-heavy chili turns you into a foghorn, whether cats can rip one, and whether that can cause pink eye. If you just want the how-to, skip down to the build sections. If you want your machine to out-fart every phone app and novelty keychain, read the sound design notes. They separate the amateurs from the virtuosos.

Strip the comedy and you’re left with physics. A fart noise is pressure passing through a small, flexible aperture with flutter. Think a reed instrument, but lazier. The membrane vibrates, the airflow modulates that vibration, and the mouth or room adds resonance. That’s why a whoopee cushion works, and why hands cupped just right can produce a rubbery honk. The characteristics that matter most:

You can synthesize the whole thing, but recordings layered with tasteful envelope shaping usually win. Still, an entirely analog squeaker rig has charm, and it never needs charging.

This is delightfully low tech and remarkably effective. It hides in plain sight, runs silent until you trigger it, and produces a satisfying variety of fart noises without a speaker.

Core idea: drive a flexible reed with a small motor and airflow, using a squeezable bulb or micro air pump to supply pressure. If you’ve ever squeezed a bike horn without the bell attached, you know the sound. We’ll tune the reed and the airflow path to get the comedy right.

Parts and tools you’ll want on hand:

Build notes based on trial and error:

Start with the reed block. Carve or print a flat channel about 20 mm long and 5 to 8 mm wide. Lay the latex over it and clamp with a washer that has a 3 to 4 mm opening. That small aperture is your “exit.” Tightening the clamp raises pitch, loosening lowers it. Don’t over-tighten or the membrane won’t vibrate. The sweet spot is where a quick puff yields a rude chirp that decays.

Plumb the squeeze bulb to the channel’s inlet with silicone tubing. Keep bends gentle. Kinks kill the effect.

Mount the vibration motor on the reed block’s side using a tiny pad of double-sided foam tape. You don’t need much amplitude. Too much shake breaks the airflow and produces a mosquito whine. If you hear a metallic buzz, you’ve coupled the motor directly to your enclosure. Add a thin rubber isolation pad.

Test with breath first. Short puffs should make short toots. Longer steady air should produce a basso honk that slides down in pitch as pressure falls. If you only get a wheeze, open the aperture slightly. If it squeals like a balloon’s neck, add a second layer of latex or move the clamp a millimeter forward.

For the enclosure, aim the reed aperture at a cavity, not directly out a hole. The chamber adds warmth. A pencil cup lined with felt transforms a nasal squeak into a rounder, familiar note. You can tune timbre by partially covering an exit vent with your finger.

If you’re using a pump, wire the pump and motor to a small perfboard with the toggle switch feeding the motor and a pushbutton feeding the pump. That way you can pre-arm the flutter and then deliver air on demand. With a bulb, you can ditch wiring altogether and trigger by hand.

Realistic touches that fool the ear: vary the airflow. One quick squeeze followed by a gentle taper sounds more convincing than a steady blast. For comedy seasoning, add a few pinholes on a sliding sleeve over the exit vent. As you slide, the resonant pitch shifts, which reads like a “lift” or “scoot.”

Durability tip: latex ages. Keep spare membranes. Nitrile lasts longer but loses some sparkle. Thin surgical glove fragments hit a nice middle ground.

Expected cost: 15 to 40 dollars, depending on whether you already have a pump and switches. Time: an hour if you’ve done any light making before, two if you’re tuning for realism.

Phones can play a fart sound effect, sure, but that’s cheating. Building your own gives you control, better speakers, and a lot of proud tinkerer energy. This one uses a microcontroller, a small class D amplifier, and a decent speaker. With proper samples and some envelope shaping, it will beat the novelty store toys by a mile.

Core components and why they matter:

On the software side, focus on sound shaping rather than fancy UI. You want:

You can record your own samples with a dynamic mic and a towel over the mic body to avoid plosives. Clap track style naming helps at the bench, but keep labels sensible on the card. If you’d rather not record, foley methods work. Balloon neck squeaks layered with a low-frequency rumble from a floor tom sample can sound startlingly authentic once EQ’d.

Physical build choices that matter:

Speaker mount: a 3-inch driver in a 0.5 to 0.8 liter sealed box gives a good thump. Thicker baffles reduce rattles. A 3D printed grill keeps fingers out.

Button layout: separate short-poot, medium, long, and “mystery” buttons. The mystery button shuffles among your top five favorites with variations. Color code them if you like, but you’ll memorize them quickly.

Enclosure finish: matte paint hides fingerprints and looks less like a science fair project. I’ve embedded mine in an old paperback book once. Cut a cavity, glue the spine, and line it with foam. The irony of classic literature harboring a digital flatulence cannon never gets old.

Battery life: at moderate volume, a single 18650 cell can run a 3 W amp and ESP32 for 6 to 10 hours, longer if you throttle. Add a low-battery LED. Nothing ruins a prank like silence when you press the big red button.

Firmware niceties: debounce your buttons in software. Add a “do not repeat last sample” rule. Keep a hidden startup combo that plays a dignified piano chord in case you need to demonstrate “serious” capability on short notice.

A great fart sound fools the ear for a split second. The listener’s face goes blank, then grins or glares. That little delay is your measure. Cheesy, over-bright squeaks from a phone app rarely hit it. Here’s how to dial in the realism.

Room resonance matters. The same sample in a tile bathroom and a carpeted living room reads completely differently. You can simulate this with subtle convolution reverb, but in a hardware box, choose the enclosure carefully. A PVC tube extension on the speaker port adds a touch of boom, but go easy or it turns into a subwoofer demo.

Volume discipline keeps you classy. A whispering pfft at a dinner table plays better than a cannon blast. Add a thumbwheel on the side and learn to ride it.

Variety beats quantity. Five archetypes cover almost every scenario: the nervous chirp, the confident honk, the slow roll, the squeaky chair ambiguity, and the traitorous surprise. Once those are strong, everything else reads like a remix.

Comedy timing is craft. Trigger just after someone stands, not as they plant their feet. Let a conversation hit a lull, then go. If you must go big, stack two short ones with a small gap. That gap is comedy gold.

Why do beans make you fart? Beans are rich in oligosaccharides that your small intestine doesn’t digest well. Gut bacteria in the large intestine feast on them, producing gas. If you ramp up fiber slowly over a week, the bacteria population shifts and the fireworks calm down. Soaking beans and discarding the soak water helps a bit, but the main effect comes from your microbes getting used to the menu.

Why do my farts smell so bad all of a sudden? Usually diet. Sulfur-rich foods like garlic, onions, broccoli, and eggs load the system with sulfur compounds like hydrogen sulfide. High-protein meals can do it too. Short-lived changes after a big weekend are normal. Persistent changes with pain, bloating, or weight loss deserve a chat with a clinician.

Do cats fart? Absolutely. Most cat farts are stealthy and odor-light because they move gas efficiently, but on high-fat diets or after gobbling air while eating, they can produce impressive results. Dogs are less discreet, as every dog owner knows.

Can you get pink eye from a fart? It’s a hardy myth. Bacterial or viral conjunctivitis can spread from contaminated fingers to eyes. Air alone isn’t the vector. Hygiene is the culprit. Don’t rub your eyes after handling anything questionable, and you’ll be fine.

Why do I fart so much? Frequency varies widely. Ten to twenty passages a day can be normal. Rapid changes, constant bloating, or pain suggests you should look at diet, swallowing air habits, and meds. Sugar alcohols in “sugar-free” gum and mints are common culprits.

Does Gas-X make you fart? Simethicone, the active ingredient, reduces surface tension of bubbles so small bubbles coalesce into larger ones. That can make gas easier to move along, which some people perceive as more passing, but with less pressure. Over-the-counter simethicone is generally safe, but if you find you rely on it daily, look upstream at diet and timing. Some folks also ask, does gas x make you fart more or less? The answer is less dramatic pressure and sometimes more audible movement. Your mileage may vary.

Why do my farts smell so bad all of a sudden after antibiotics? Not uncommon. Antibiotics can scramble your gut flora. That can alter fermentation patterns for a bit. Yogurt, kefir, or a simple, steady diet can help stability return. If it lingers for weeks, consult a professional.

How to make yourself fart when you’re uncomfortable: small walks help. Knees-to-chest stretches move gas pockets along. Warm liquids, gentle belly massage, and position changes (left side lying) usually do more than any trick.

Harmless fun turns sour when you punch down. Pranking your brother while he refills the snack bowl? Green light. Humiliating a stranger at work? Hard red. Always think power dynamics. Your job title, their role, the setting. If anyone asks you to quit, quit. Best pranks end with a laugh, not a meeting with HR.

Noise etiquette helps. Restaurants and theaters are sacred. Outdoor gatherings, backyard barbecues, tailgates, and April 1 are the natural habitats. Don’t prank the dog repeatedly. They can’t consent, and some get anxious.

For kids, keep the playtime brief. Hand them the machine, let them giggle, then set boundaries: not at school assemblies, not during someone’s recital. Most understand if you explain that comedy needs a stage, not a hostage audience.

You can go deep here, and if you enjoy craftsmanship, it’s worth it. I’ve tried the following and kept the ones that genuinely improved the bit.

A pressure sensor on the mechanical build turns finesse into a controller input. Mount a small barometric or differential pressure sensor in the airflow path and light an LED strip that rises as pressure increases. Overkill? Yes. Satisfying? Also yes.

A hand-sanitizer bottle, emptied and washed, makes a perfect stealth squeeze bulb. The click cap can double as a momentary switch if you glue a tactile under it. The workplace camouflage is A-plus.

For the digital box, add a crossfade engine that stitches tiny grains of samples. You can improvise a longer passage from shorter clips without the loop point giving itself away. Keep grains in the 50 to 120 ms range and randomize start frames.

If you’re the type who brings audio gear to a picnic, a compact battery-powered subwoofer under the bench will sell the illusion beyond anything else. Humans locate low frequencies poorly. People will blame the bench leg. Fair warning: this becomes a whole project by itself.

Mechanicals clog if you blow dust into them. A puff of clean air backward through the reed clears debris. Keep spare membranes in a small zip bag, out of sun. If your enclosure picks up a funk, a light wipe with isopropyl alcohol and a few hours open-air dry brings it back. Keep oils off latex, or it will degrade faster.

Digital builds hate loose grounds. If you hear whine, star-ground your returns and twist your speaker leads. Low battery also produces ugly artifacts in class D amps. If it starts to sound like a kazoo, charge it.

If you stash a machine in a car for road-trip comedy, remember heat kills lithium cells https://fartsoundboard.com/pets/ and softens hot glue. Use screws and standoffs in anything that lives in a summer trunk.

There’s a cocktail named the duck fart shot. It’s a layered mix, usually Kahlúa, Bailey’s, and whiskey. It earned the name on looks and timing. Nothing to do with our machine, but the name pops up whenever people swap recipes at parties. If you bring your machine to a party that serves those, you’ll become either the star or the villain. Roll the dice.

Unicorn fart dust, the edible glitter trend, shows up on cupcakes in my neighborhood. Resist the urge to mount your speaker under a serving tray. That crosses the line from prank to kitchen sabotage.

Certain corners of the internet pair crude humor with comic characters, even trading collectibles like a so-called fart coin or making jokes about a harley quinn fart comic. Keep your project on the sunny side. Comedy ages better without dragging anyone into it.

Fart spray exists, and it is potent. The classic “liquid stink” uses sulfur compounds that linger in upholstery and can make small rooms uninhabitable for hours. If your goal is laughs rather than grudges, stick to sound. It resets instantly, and no one needs to febreze their coat.

If you ever get on a kick of testing diets “for research,” your own system will tell you when you’ve gone too far. Extremely foul odor along with persistent cramps, diarrhea, or weight change is not a comedy bit. See a clinician. The gut has a long memory.

Mechanical reed machine: cheap, tactile, no charging, and wonderful in small rooms. It rewards patience with membrane tuning and clever airflow. If you want analog charm and a stealth desk prank, this is your winner.

Digital soundboard: louder, more variety, more control. It shines at gatherings and handles outdoor spaces better. It takes more parts and soldering, but once built, you can swap new samples in seconds. If you love knobs and code, go this route.

I’ve taken a mechanical reed version to a quiet office and learned the art of the single, whispered pfft behind a coffee mug. I’ve also toted the digital rig to a backyard birthday and watched a semicircle of adults rate each blast like Olympic judges. The trick isn’t the machine. It’s your restraint. Let the room breathe. Pick your moments. If anyone looks truly mortified, shift the blame to the dog or the patio chair and change the subject.

When you nail the timing, you’ll see it. Shoulders drop, faces crack, and someone inevitably says, “Okay, who brought that?” That’s your cue to show the box and accept your laurels. Then, like any responsible artisan, take requests and keep it short. Leaving a party with people still laughing beats staying until someone hides your batteries.

Build it. Tune it. Treat it like a musical instrument with a very silly repertoire. The world already has a thousand identical phone apps. Yours will have soul, a bit of workshop sweat in the joints, and a sound that makes a room stop, then erupt. And that, for the price of a few switches and a membrane, is a bargain.