Sensitivity is how much sound a speaker produces for one watt at one metre; impedance is the electrical load it presents. The first tells you how loud, the second tells you whether your amplifier can do it comfortably.
Sensitivity, and why 3 dB is a large number
It is stated in decibels at 1 W and 1 m. A speaker at 90 dB plays as loudly on one watt as an 87 dB speaker does on two. Across the range of speakers in this catalogue that difference is worth more than most amplifier upgrades.
Impedance, and the number that is not printed
Nominal impedance — 4, 6 or 8 ohms — is an average. The actual load varies with frequency and dips below the nominal figure somewhere. That dip is what makes a receiver run hot, and it is rarely published.
Where this matters most in a home cinema
The surround and height channels, driven by a receiver’s last and least generous amplifiers. A sensitive, easy-to-drive speaker in those positions asks far less of the machine than an insensitive one.
What neither figure tells you
How it sounds. Sensitivity and impedance describe a match between speaker and amplifier, not quality — and a very sensitive speaker will also reveal amplifier noise more readily.
Questions people actually ask
Is a 4-ohm speaker a problem for my receiver?
It depends on the receiver, and manufacturers state the loads they support. Nominal impedance also hides a minimum that dips lower in places, which is why a receiver rated for 6 ohms can struggle with a nominal 4-ohm speaker in some passages.
How much does 3 dB of sensitivity matter?
The same as doubling amplifier power. A speaker rated 3 dB more sensitive plays as loud on half the watts, which is why sensitivity often matters more than the amplifier specification when a system is put together.
Last reviewed 4 September 2026