Wattage is the most quoted speaker spec and one of the least useful. It describes how much electrical power an amplifier can deliver, which is not the same as how loud a speaker plays, and it is measured differently by every manufacturer. This page explains why, and what to look at instead.
The Numbers Aren’t Comparable
Here is how the “Output Power” field actually reads across speakers ranked on this site:
110W (Woofers: 2x50W, Tweeters: 2x15W)50W total (25W per speaker)100w Per Speaker200W AC / 180W battery3 x 73W80W
Total or per speaker? RMS or peak? On mains or on battery? Across all drivers or just the woofer? Every one of those choices doubles or halves the number, and manufacturers pick whichever flatters. A “200 W” speaker and an “80 W” speaker may produce identical volume.
Even where two brands both quote honest RMS totals, the figure still says nothing about efficiency - how much of that power becomes sound rather than heat.
What Actually Determines Loudness
Driver area and excursion. Moving air is the job. A larger cone moving further displaces more air, and that is what loudness is. This is why size class predicts volume far better than wattage.
Sensitivity, on passive speakers - how loud the speaker plays per watt. It’s logarithmic, so every 3 dB halves the power needed. An 87 dB speaker needs twice the amplifier of a 90 dB one. This is the number that actually connects watts to volume, and it’s why best passive speakers for tube and low-power amps is built on it rather than on power handling.
Tuning and DSP limits. Most portable speakers are limited by their processing long before their amplifier. A speaker that compresses and pulls its own bass back at high volume isn’t running out of watts.
The One Place Watts Nearly Matter
Matching an amplifier to passive speakers. Here you do need enough power - but “enough” is calculated from sensitivity, room size and listening distance, not from a number on the speaker’s box. The passive speaker buyer’s guide walks that calculation.
Note the direction of the usual mistake: underpowering causes more blown tweeters than overpowering, because an amplifier driven into clipping sends distorted, high-energy signal to the tweeter. Headroom protects speakers.
On powered speakers and portables, ignore wattage entirely. The designer matched the amplifier to the drivers; there is no decision left for you to make. A 40 W active studio monitor routinely plays louder and cleaner than a 100 W passive pair on a budget amp.
What To Use Instead
- Size class - the single best predictor of volume and bass. See the portable buyer’s guide.
- Max Volume / Max SPL, where measured, in the spec table.
- Bass extension for how low it goes.
- CEA-2010-A for subwoofers - an actual standardized output measurement.
- The ranking position, which is based on measurements rather than claims.
Last Updated August 07, 2026