It features a new combination of a pair of Kevlar® cones for delivering its bass and midrange. The lower cone is dedicated to bass, which relieves the upper bass/midrange unit of the duty to handle heavy bass and leads to clearer, crisper midrange than you might find in smaller speakers. The Nautilus™ tube-loaded, aluminium dome tweeter, featuring a new surround material to improve spaciousness and imaging, adds needle-sharp top end all the way to 50kHz and beyond. The improvements to the drive units in the new 600 Series make it possible, for the first time, to introduce a minimalist crossover to the range. The use of components that are fewer in number but higher in quality – hand-picked in exhaustive listening tests – reduces the degradation of the signal significantly. So, whether you’re enjoying hi-fi or home cinema, what you hear is that much closer to what was recorded. Visually, a refreshed, contemporary design language and a widened choice of wood finishes allows the 684 to fit in effortlessly with any interior.
SPECIFICATIONS
| Description | 2.5 – way vented-box system |
| Drive units | 1x ø25mm (1 in) aluminum dome high-frequency1x ø165mm (6.5 in) woven Kevlar® cone bass/midrange1x ø165mm (6.5 in) woven Kevlar® cone bass |
| Frequency range | -6dB at 34Hz and 50kHz |
| Frequency response | 44Hz-22kHz ±3dB on reference axis |
| Dispersion | Within 2dB of reference responseHorizontal: over 60Âş arcVertical: over 10Âş arc |
| Sensitivity | 90dB spl (2.83V, 1m) |
| Harmonic distortion | 2nd & 3rd harmonics (90dB, 1m)<1% 90Hz – 22 kHz<0.5% 120Hz – 20kHz |
| Nominal impedance | 8Ω (minimum 3.0Ω) |
| Crossover frequency | 350Hz, 4kHz |
| Recommended amplifier power | 25W – 200W into 8Ω on unclipped programme |
| Max. recommended cable impedance | 0.1Ω |
| Dimensions | Height: 910mm (35.8 in)(not including plinth or feet)Width: 198mm (7.8 in)Depth: 300mm (11.8 in)(including grille and terminals) |
| Net Weight | 18.2kg (40.1 lb) |












