Simple Explanation

A setup where two amplifier channels work together to power a speaker by pushing and pulling the signal, increasing power output.

Concise Technical Definition

An amplifier configuration where the speaker is connected between two amplifier outputs operating in anti-phase, effectively doubling voltage swing and theoretically quadrupling power output, assuming the power supply can handle the current demand.

Layman-Friendly Analogy

Like two people pushing and pulling a swing at the same time from opposite ends—it moves with more energy than if only one person were doing it.

Industry Usage Summary

Common in car audio and compact systems to maximize power output using two channels. Though theoretically capable of quadrupling power, real-world results are limited by the amplifier’s current supply. Often labeled “bridged mode” in amplifier manuals and used to drive subwoofers with higher power from standard stereo amps.

Engineering Shortcut

BTL = Double voltage swing → ~4× power (if current allows)

Full Technical Explanation

Bridge-tied load (BTL) is an amplifier configuration where a speaker is connected between two amplifier outputs that are 180° out of phase. This doubles the voltage swing across the speaker, resulting in four times the power (P = V²/R), assuming the amplifier can deliver the required current. One channel acts as an inverting current amplifier while the other delivers the signal directly. Although often described as producing 4× power, practical limitations such as power supply current capacity typically reduce actual performance.