How do I calculate the required amplifier power for my speakers?

The calculator uses the formula: P = 10^((SPL - Sensitivity - 20×log₁₀(distance))/10). It considers speaker sensitivity, listening distance, target SPL, and adds headroom for dynamic peaks. Room acoustics are also factored in, as reverberant rooms require less power than anechoic spaces.

What is speaker impedance and why does it matter?

Speaker impedance (in ohms) determines how much current the amplifier must supply. Lower impedance (4Ω) draws more current than higher impedance (8Ω). When connecting multiple speakers, impedances combine - speakers in parallel reduce total impedance, while series connections increase it. Amplifiers must be rated for the final load impedance.

What's the difference between Class A, AB, and D amplifiers?

Class A offers highest fidelity but low efficiency (20-30%). Class AB balances quality and efficiency (50-70%), common in studio monitors. Class D achieves 85-95% efficiency, ideal for high-power applications and portable systems. The calculator recommends the best class based on your application and priorities.

How much headroom do I need in my amplifier?

Headroom prevents clipping during dynamic peaks. For music, 3-6dB headroom is typical. Live sound benefits from 6-10dB. Critical listening and studio monitoring may need 10dB+. The calculator factors your desired headroom into power recommendations.

Power Amplifier Calculator

Pro

Calculate power requirements, impedance matching, and compatibility for professional audio amplifier systems. Optimize speaker-amplifier pairing for optimal performance.

Beginner Mode

Simplified interface with recommended defaults

BeginnerPro

Speaker Specifications

Enter your speaker's basic specifications

Speaker Impedance (Ω)

Speaker Power (RMS / Continuous) in Watts

Speaker Sensitivity (dB @ 1W/1m)

I know it

Typical: 85-92 dB (home) • 95-100 dB (PA) • 100+ dB (horn-loaded)

What type of amplifier do you need?

Your Requirements

Tell us about your listening environment

What do you want to find?

Listening Distance (meters)

Target Volume Level (dB SPL)

70-80 dB: Background music • 85-95 dB: Moderate listening • 100+ dB: Live concerts

Budget$5,000

$100$5,000

Recommended defaults applied

Headroom: 3 dB (industry standard) • Room: Medium Room (+4 dB gain) • Amp Class: Class AB (balanced quality/efficiency)

Switch to Pro Mode for full control over these settings.

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