The audio performance of the Sony CMT-CX5 is pleasing. It accentuates the treble somewhat at the expense of bass and midrange, but music is notably clear and detailed. Sony clearly recognises this may not please the younger big beat enthusiasts, and the DSGX mode focuses on both these two shortcomings and is fairly successful.
It adds greater depth, and while the CX5 still isn't bass-heavy by any means it is arguably better off for it, maintaining impressive fidelity as the volume is cranked up. Distort creeps in a little at maximum volume (which with 40W to play with is loud, if not window shaking), but it is saved by the CX5's greatest attribute: its stereo separation.
Just as MP3s saw users forget about audio quality in favour of track quantity, stereo separation has become a near-dead criteria for the legions of dock buyers focused on near-mono bombastic delivery. Sony may show the CX5 with its speakers pushed against the main unit (there is no physical way of locking them together), but the further apart the speakers are positioned the better they sound.
The supplied cables for each speaker are just short of 90cm each and mean a wide radius of sound can be created which clearly distinguishes the left and right channels and consequently the placement of specific instruments and effects. It also means the speakers can be positioned independently to best fill any shape of room regardless of the Sony CMT-CX5's primary position and cuts down the need to max out the volume.
We've seen the Arcam rCube and Audyssey South of Market docks most faithfully recreate this by angling their speakers at 45 degrees inside their chassis, but they cannot compare to actual physical distance.
That is not to the Sony CMT-CX5 is sonically superior overall to either of these more expensive docks. Sony is not trying to cause chaos in the premium dock sector, but what it does is ask serious questions of those with up to £200 to spend. In this context the CX5 easily outperforms its similarly priced dock alternatives, gives you a CD player and DAB radio (admittedly largely redundant for those with internet-radio-sporting devices). Other niceties include an alarm clock and sleep timer modes, and a neat remote with bags of functionality including the ability to navigate iPod content. Against is an almost deliberate lack of cool, no wireless functionality and a sunken Apple dock which means an iPad cannot be attached.
Ultimately whether you should buy the Sony CMT-CX5 comes down to priorities. It lacks gimmicks and may not be as portable as an equivalent dock, but it offers a superior audio experience to any equivalently priced dock, brings your dusty CD collection back to life, drops in DAB for good measure and won't break the bank - particularly with online discounts. The CX5 is a brave move from Sony and one it just about pulls off.