Gain Setting Calculator

Calculate the exact AC voltage to set your amplifier gains using the voltage method. This gives you a verifiable number to measure with a multimeter.

THE FORMULA

V = √(P × R)

Voltage = Square Root of (Power × Impedance)

Target Power

Target RMS Power (Watts)

Speaker Impedance

Final impedance of your speaker/subwoofer wiring

Headroom (Optional)

Your Amplifier (Optional)

Enter your amp specs to verify it can deliver the target power

Rated Power (W)

@ Impedance (Ω)

SET YOUR MULTIMETER TO

44.7 V

AC Volts at speaker terminals

Calculation Breakdown

Target Power:1,000 W

Impedance:2 Ω

V = √(1000 × 2)44.72 V

Actual Power Delivered:1,000 W (100%)

Current Draw (I = V/R):22.4 A

Amp Compatibility

✓ AMP CAN DELIVER

Amp output @ 2Ω:1,500 W

Your target:1,000 W

Amp headroom:+50%

Amp clips at:54.8 V

How to Set Your Gains (Voltage Method)

Equipment Needed

•Digital multimeter (AC voltage mode)
•Test tone at 0dB (usually 40-50Hz for subs)
•Head unit or DSP with known output level

Steps

Set all gains to minimum
Play test tone at 0dB (or -5dB for headroom)
Set head unit to ~75% volume (or max clean output)
Connect multimeter to speaker outputs (AC mode)
Slowly increase gain until you reach 44.7V
Lock the gain knob - you're done!

⚠️ Important Notes

• Use a TRUE RMS multimeter for accurate readings
• Disconnect speakers while measuring (use a resistor load or measure at the amp terminals)
• If using -5dB test tone, this calculator already accounts for it - use 0dB headroom option
• Real impedance varies with frequency - nominal impedance is an approximation

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