# Filter design
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## Microsims — p5.js
### Filter design (p5.js) · `spec → H`
<div class="microsim-player">
<iframe src="https://editor.p5js.org/sciencenibber/full/M8gNVn6hH" width="100%" height="480" frameborder="0" loading="lazy" sandbox="allow-scripts allow-same-origin" title="Filter design — p5.js microsim"></iframe>
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*Turning a frequency-response specification into realizable coefficients — trading passband, stopband, and order.*
**Open in the editor:** [▶ fork this sketch](https://editor.p5js.org/sciencenibber/sketches/M8gNVn6hH) · movement *III · Filters & filter design* · library `p5js`
### Related microsims
Live sims on neighbouring articles — 6 of them inside this article's own Wikipedia link tree:
- [[Decibel]] *(in tree)*
- [[Feedback]] *(in tree)*
- [[Frequency_domain]] *(in tree)*
- [[Frequency_response]] *(in tree)*
- [[Impulse_response]] *(in tree)*
- [[Signal-to-noise_ratio]] *(in tree)*
*Sim hosted off-article; the article owns the reference, not the runtime (WIKI_RULES §10.4). Placed by `g08_place_microsims.py`.*
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## Links (Wikipedia order)
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`Aliasing` · `All-pass_filter` · `Anti-aliasing_filter` · `BIBO_stability` · `Band-pass_filter` · `Band-stop_filter` · `Beat_(acoustics)` · `Causal_filter` · `Computer_arithmetic` · `Computer_memory` · `Computing` · [[Decibel]] · `Differentiator` · `Digital_biquad_filter` · `Digital_delay_line` · `Digital_filter` · `Discrete-time_Fourier_transform` · `Electronic_filter` · [[Feedback]] · `Filter_(signal_processing)` · `Filter_theory_(sociology)` · `Finite_impulse_response` · `Fourier_transform` · [[Frequency_domain]] · [[Frequency_response]] · `Group_delay_and_phase_delay` · `High-pass_filter` · `High-resolution_audio` · `Hilbert_transform` · [[Impulse_response]] · `Infinite_impulse_response` · `Instability` · `Instructions_per_second` · `Integrator` · `James_Kaiser` · `Kronecker_delta` · `Limit_cycle` · `Linear_combination` · `Linear_filter` · `Linear_phase` · `Low-pass_filter` · `Mechanical_filter` · `Moving_average` · `Nyquist_frequency` · `Octave` · `Parameter` · `Phase_(waves)` · `Phaser_(effect)` · `Prototype_filter` · `Remez_algorithm` · [[Signal-to-noise_ratio]] · `Slope` · `Steady_state` · [[Time_domain]] · `Transient_(acoustics)`
> Signal Processing concept · part of the Signal Processing Portal · movement III · !24 回路 kairo.svg
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*Rendered from the live microsim (▶ motion).*
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## See it next
[](FIR_filter)
*→ FIR filter*
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---
Back to Signal Processing Portal · the room · Semiotic gateway
## What it is
Filter design is the process of choosing a filter's structure and coefficients so that its frequency (or time) response meets a target specification while remaining stable, causal, and implementable at acceptable cost.
## How it works / why it matters
Designers start from specifications — passband and stopband edges, ripple, attenuation, and phase or delay requirements — and select a method to meet them. Classic IIR approaches derive filters from analog prototypes (Butterworth, Chebyshev, elliptic) mapped to digital form via the bilinear transform or impulse invariance, while FIR methods use windowing, frequency sampling, or optimal equiripple (Parks–McClellan) design. The craft is trading response sharpness against filter order, delay, and numerical robustness.
## Signs & universals
Instantiates: filter frequency spectrum
## Related
FIR filter · IIR filter · Impulse invariance · [[Frequency_response]] · Digital filter · Filter (signal processing)
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*Built to the [[WT!P5_js_Microsim_Master_Class|p5.js Master Class]].*
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## Wikipedia : Wikitube
**Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Filter_design) : [Wikitube](https://en.wikitube.io/wiki/Filter_design)
## Previous hub tags
Tree parent: [[Reliability_engineering]].
Legacy hubs: none.
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*Sources: 1 legacy note. Minted wave 1, 2026-07-30 (v1.6 order).*