Subwoofer Wiring Calculator
Find the final impedance for any number of single or dual voice coil subs, with a live wiring schematic and amp-safety check.
Inputs
Schematic
Each colour = one subwoofer · 1.00 Ω seen by the amp
How it works
When you connect several voice coils to one amplifier channel the amp sees a single combined load. Wiring changes how many ohms that load is, and since amps deliver more power into lower impedance (until they hit their limit), wiring is your power knob.
Series: Z_total = Z1 + Z2 + … + Zn
Parallel: 1/Z_total = 1/Z1 + 1/Z2 + … + 1/Zn
For n identical coils: series = n·Z parallel = Z/n
Strings of k coils in series, g strings in parallel:
Z_total = Z · k / gRules of thumb: never go below the lowest impedance your amp is rated for, it will overheat and shut down (or die). Wiring to a higher load is always safe, you just get less power. Always wire with identical coils and use the same polarity (+ to +, − to −) on every driver, or the drivers will cancel each other out.
The colours in the schematic mark which coil belongs to which subwoofer. In a dual-voice-coil sub, the two coils of one sub usually sit next to each other. Real amplifiers rarely double their power exactly with each halving of impedance, use the Amp Power calculator to see ideal numbers.