I’ve heard the Nightingale described as an Italian variation on the panel theme. Like classic panels, it’s a dipole design, though it differs from most current models in using conventional moving-coil drive units, and housing them in a package of considerable physical elegance.The £8,000/pair Nightingale Concentus CTR2 – the full name is important, as others around the globe have also chosen the Nightingale name – is the only loudspeaker in a generous range of audio electronics produced under the Nightingale banner since 1995. Alongside the CTR2 loudspeakers, Nightingale makes an extensive range of valve amplifiers and a number of mains conditioning units.
The elegant shape tapers in gently curving hardwood (walnut) sides to a top that’s half the width of the base. The unit sits on an attractively shaped and fluted base which can accommodate spikes and ensures fine physical stability. The only real aesthetic criticism is that the front view is rather large (likewise the black grille), as these are unavoidable consequences of dipole/panel operation. You can leave the grilles off, revealing the attractive hardwood front panels (though the graining doesn’t quite match between the pair), but the disposition of the mirror-imaged drivers can look a trifle odd. The floorcoupling arrangements are a trifle primitive: the threeper-speaker spikes should certainly sit properly without rocking, but these pretty chrome-finished cones lack lock-nuts and are simply too short when fixed into the recessed underside of the plinth – I ended up using large Michell cones instead.
What really distinguishes this speaker from the overwhelming majority is that there’s no enclosure as such. Instead of attempting to remove or make some use of the out-of-phase signals generated from the rear surfaces of the cones, the CTR2 simply lets them waft out into the room.
This has a number of crucial implications. On the plus side, there is by definition no enclosure here, so there’s consequently a complete freedom from most of the boxy effects that plague most other loudspeakers. These will include the internal reflections and standing waves generated by the rearward radiation, and the vibrations created in the enclosure panels themselves, all of which threaten to colour up the sound. The front panel here can introduce some coloration of course, but only from vibrations generated by the drive units themselves, as there are no associated enclosure pressures.