Cartoon sound has a fixed vocabulary (the boing, the pop, the slide whistle, the splat, the sad trombone), and its job is to be read instantly as a joke. That reverses the usual rules of this library: realism is wrong and exaggeration is correct. It is also one of the most searched tags on free libraries.
Every clip shows the exact prompt that produced it. The render script reads its prompts from the same file as this page. Copy one, change a word and generate your own.
cartoon boing, comedic metal spring twanging with a wobbling pitch bend, bright and dry
cartoon pop, single bright mouth-like bubble pop with a hollow tone, very close mic, dry
slide whistle sweeping quickly upward, bright comedic glissando, dry and close
slide whistle sweeping downward like a falling body, comedic glissando ending in a splat, dry
cartoon splat, wet exaggerated goo impact with a comedic squelch, close and dry
cartoon running feet, rapid comedic scampering with a rhythmic tumbling patter, dry, seamless loop
cartoon anvil falling with a descending whistle and landing with a huge comedic clang and a wobble
comedic sad trombone, four descending muted brass notes with a wah wah bend, dry
vinyl record scratching to an abrupt stop, classic comedic freeze-frame effect, close and dry
cartoon eating, exaggerated rapid crunching followed by a huge comedic gulp, close mic, dry
These models respond to physical description. Name the material, the action and the space.
cartoon boing, comedic metal spring twanging with a wobbling pitch bend, bright and dry
"Pitch bend" and "wobbling" make it comic. A real spring twang without the exaggerated bend sounds like hardware.
cartoon pop, single bright mouth-like bubble pop with a hollow tone, very close mic, dry
"Mouth-like" is the key word. The classic cartoon pop was performed by a person, and asking for that origin gets the hollow character.
slide whistle sweeping downward like a falling body, comedic glissando ending in a splat, dry
Naming what the sweep represents sets the timing. A fall accelerates, and the model shapes the glissando to match.
vinyl record scratching to an abrupt stop, classic comedic freeze-frame effect, close and dry
Naming the use instead of the mechanism works here because the effect is so codified that the model has heard it labelled that way.
Elsewhere in this library, a generation that sounds too big or too obvious is wrong. Here it is the target. Cartoon sound is more extreme than physics allows: springs that bend further than metal can, splats wetter than any substance, falls that whistle. Use words that would be warnings elsewhere: "exaggerated", "comedic", "cartoon", "huge". They steer the model toward the animation corpus and away from the foley corpus.
Comic timing depends on a sound stopping when the joke does. Room tone smears the ending and softens the punchline, which is why almost every prompt in this collection ends with "dry" and asks for one to three seconds. If a cartoon sound is not working, it is more often too long than wrong. Trim it before you regenerate, and if you regenerate, shorten the render.
The pop, the boing, the gulp, the crunch and the whistle were originally mouths, springs and slide whistles played by hand in a studio. Prompts that point at that human origin ("mouth-like", "performed", "comedic") land closer to the classic sound than prompts describing an abstract effect, because the model learned from those performances.
The models run on your machine, which changes the cost, the privacy and what you can automate.
Weights are fetched once. After that, generation, the library and the API all work with the network off. Everything lives in one SQLite file and one folder of WAVs under ~/.soundbox, and nothing is uploaded.
Soundbox runs an MCP server in the same process, with tools for generating and listing sounds. Generated files come back as absolute paths, so an agent can copy them into a project.
Every model's terms are shown before you download it, and non-commercial weights need an explicit confirmation. Soundbox is MIT. The licence of the model that made a sound governs what you may do with it.
claude mcp add --transport http soundbox http://127.0.0.1:17494/mcpcurl -X POST http://127.0.0.1:17494/api/generate \
-H 'Content-Type: application/json' \
-d '{"model":"audiocpp-stable-audio-3-sfx","prompt":"8-bit coin pickup blip","duration_s":1}'