Use this tool to calculate the amplifier output power for an audio system consisting of an amplifier, speaker or subwoofer.
How to use the calculator
- Enter
- Amplifier RMS output power per channel
- Amplifier impedance in ohm (Ω)
- Impedance in ohm (Ω) for each speaker or subwoofer connected to the amp
- The tool will provide RMS output power from the amp
Calculator
Example Calculation
Let’s use this amplifier from DS18 as an example. It has an RMS power rating of 200 W per channel at an impedance of 4 ohm.
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If we want to match them with these JBL Speakers, with 60 W nominal power and 2.3 Ω impedance, there’s a risk that these speakers will be damaged if they are over driven. According to the calculator on this page, the amplifier will deliver 348 W of power to the speaker.
On the other hand, let’s consider speakers with 250 W RMS and 4 Ω impedance.
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In this case, the amplifier will be able to deliver 200 W RMS with the impedance match. This is a reasonably compatible solution.
Ideally, based on this speaker/amplifier matching calculator, the amplifier wattage should be between 225 and 300 Watt. When the amp power is lower than that (200 W in this case), there’s a chance that clipping will occur and result in speaker damage.
Related Tools
- Calculate the Amplifier Output Power required to provide a specified Sound Pressure Level (SPL).
- Calculate the max SPL of a speaker