Q550
speaker
$800
Used market: $575*
Specifications
6 of 6 values have a recorded sourceExpert Audio Engineering Commentary
Headroom Notes
87 dB at 2.83 V / 1 m. On an 8-ohm nominal load 2.83 V is exactly 1 W, so this figure needs no correction — which is why it can be compared directly against the 6-ohm DALI and Q Acoustics floorstanders in this batch, whose 2.83 V numbers are worth about 1.25 dB less once converted to watts.
Amplification Warning
KEF prints «8 Ohms (min.3.5 Ohms)» in a single cell, and the 3.5 is the number an amplifier actually meets. A 2.5-way floorstander with two 130 mm bass units in parallel dips where the crossover hands over, so the load is lowest exactly where a rock or orchestral crescendo puts most of its energy. Choose an amplifier rated into 4 ohms, not into 8.
What the datasheet actually says
Quoted verbatim from the manufacturer’s own page, with the date we checked it. We state what is printed, not what anyone intended by it.
«Maximum Output 110dB»
KEF prints a maximum output figure for a passive speaker without saying at what drive level, at what distance, or over what bandwidth it was reached. A passive loudspeaker has no maximum output of its own — it has whatever the amplifier feeds it, up to thermal or excursion failure. We therefore do not carry this number as a calculable field; only the sensitivity and the impedance minimum can be used to predict level.
checked 8/5/2026* Estimated with the depreciation fallback (~72% retained value). · checked on 8/5/2026