What is the Class-D Amp multi-solver?

Class-D Amp is a guided workflow that chains 2 individual PolySim solvers into one end-to-end analysis, piping each result into the next step.

Yes. Every step runs entirely in your browser using real numerics — no install, no account, no cloud cost. Custom or private solver packs are available as a paid service.

Electronics & Power Pack · Multi-Solver

Class-D Amp

PWM, filter, THD. This multi-solver chains 2 solvers into a single guided workflow — run each step in order and carry the result forward.

Workflow steps

or unlock everything with Pro →

Aliasing

open full solver →

Sampling & AliasingLive

the Nyquist theorem

Controls

Presets

Signal frequency (Hz)

Sample rate (Hz)

To capture a signal faithfully you must sample above twice its highest frequency — the Nyquist rate. Sample too slowly and a high frequency masquerades as a lower one: aliasing. Push the signal frequency above half the sample rate and watch the reconstructed wave collapse to a false, slower tone.

▶ Run in Python

Data Inspector

Nyquist frequency10.0 Hz

Statusproperly sampled

Apparent frequency3.0 Hz

Governing equation

f_{app} = f - f_{s} round (\frac{f}{f _{s}}) = 3.0 Hz, f_{N} = \frac{f _{s}}{2} = 10.0 Hz

Reading this result: Sampling at 20 Hz puts the Nyquist limit at 10.0 Hz. The 3 Hz signal sits below that, so it is captured faithfully and reconstructs at its true frequency.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

↓

Filter Designer

open full solver →

Analog Filter DesignerLive

RC & RLC frequency response

Controls

Presets

Resistance R (Ω)

Capacitance C (nF)

Passive filters shape a signal's frequency content with resistors, capacitors, and inductors. An RC low-pass or high-pass has a cutoff at 1/(2πRC) where the response drops 3 dB; an RLC bandpass resonates at 1/(2π√(LC)) with sharpness set by its quality factor Q.

▶ Run in Python

Data Inspector

Cutoff fc1.6 kHz

Resonance f₀5.0 kHz

Quality factor Q0.32

Governing equation

∣ H (f) ∣ = \frac{1}{1 + ( f /1592 ) ^{2}}

Reading this result: Low-pass: signals below the 1.6 kHz corner pass, above it they roll off at 20 dB/decade, and the response is exactly 3 dB down right at the corner.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

Need a private, branded version?

We build custom solvers and workflows for labs, firms, agencies, and courses — your parameters, your branding, your data.

Explore Custom Solver Sets →

More in the Electronics & Power pack

Filter + Amplifier Chain Power Supply Designer RF Front End Sensor Signal Chain Motor Driver Audio Amplifier Oscillator Designer PCB Thermal

Frequently asked questions

What is the Class-D Amp multi-solver?: Class-D Amp is a guided workflow that chains 2 individual PolySim solvers into one end-to-end analysis, piping each result into the next step.
Is it free to use?: Yes. Every step runs entirely in your browser using real numerics — no install, no account, no cloud cost. Custom or private solver packs are available as a paid service.