The latter has much to do with this speaker’s impressively wide dynamic range and fine reproduction of low level information. That in turn may well be down to improved control over enclosure vibrations, perhaps due to the extra reinforcement and stiffening provided by the additional vertical dividing panels that are used to create a transmission line.
Stereo imaging is about as good as it gets, with well layered perspectives on material with appropriately simple miking. Fine details and airiness were convincingly portrayed, and some clues to various recording studio techniques could also often be heard. Coloration here is also very low, probably thanks mainly to the very smooth delivery of that new midrange unit, which ensures that the voice band is generally and rather unusually even, as well as restrained.
Earlier in this review, I mentioned that introducing Vertex AQ’s terminal links was usually a good guide to the quality of a speaker. Doing so did indeed create a significant improvement, confirming the Twenty.26’s underlying qualities. This is unquestionably a superb loudspeaker, with the sort of restrained and laid back balance that ensures it will never become aggressive even when playing music at high levels. It can become a little untidy when loud, revealing plenty of power handling but also minor timing limitations compared with the fact.12. However, at any normal level it’s beautifully balanced, with ample bass weight and an excellent dynamic range. PMC’s Twenty series has proved to be its most commercially successful to date. With models like the Twenty.26 in that range, it’s not hard to see why! Highly Recommended.
What is RAOS?
Loudspeaker companies have used laser interferometry for many years to examine the mechanical behaviour of enclosures, diaphragms and so on, but the National Physical Laboratory’s RAOS (rapid acoustico-optic scanning) approach avoids any mechanical contact and actually measures changes in the air’s refractive index in front of a loudspeaker producing an audio signal. These correspond to the pressure variations in the air, which are the actual soundwaves themselves of course, establishing the detailed directivity of a loudspeaker more rapidly and less invasively than traditional techniques. Ollie Thomas (son of PMC proprietor and founder Peter Thomas) has been working with the NPL to apply RAOS in several recent designs, examining, for example, the shape of the 50mm midrange dome’s front flange, an ideal problem since the technique is currently only applicable above 500Hz.
Freq response: 27Hz – 25kHz
Sensitivity: 86dB/W (measured at 88dB/W)
Effective ATL: 3.3m (11ft)
Impedance: 8 Ohms (measured 4 ohms min.)
Drive Units: LF: 177mm cast frame with doped 125mm paper cone. MF: 50mm twenty-series dome. HF: PMC/SEAS 27mm soft SONOLEX dome
Crossover frequencies: 380Hz, 3.8kHz
Input connectors: 3 pairs 4mm socket/binders
Size (HxWxD): 106.2(+25 spikes) x19x43.9(+16 grille)mm
Available finishes: walnut, amarone, diamond black, oak
Price: £5,750 per pair
Manufacturer: Professional Monitor Company
Tel: +44 (0)8704 441 044