Speaker sensitivity and impedance, explained
These two numbers decide how easily a receiver can drive a speaker — and whether your pairing will play nicely.
Sensitivity: loudness per watt
Sensitivity (in dB) tells you how loud a speaker plays from one watt. Every 3 dB is roughly double the power for the same volume, so a 90 dB speaker needs half the power of an 87 dB one to hit the same level. Higher sensitivity means an easier life for your receiver.
Impedance: the electrical load
Impedance (in ohms) is the electrical resistance the speaker presents. Lower impedance draws more current. Speakers that dip below 4Ω demand a receiver or amplifier built to supply it — otherwise you get distortion or shutdowns at volume.
Reading them together
A low-sensitivity, low-impedance speaker is the most demanding combination and wants serious amplification. A sensitive, benign-impedance speaker is happy on almost any receiver. Our compatibility checker weighs both against the receiver you have chosen.