Digital signal processing rules the field of front surround. Except when it comes to US loudspeaker maker, Polk Audio. Its surround bar doesn’t have integrated circuits, or even a power cord. Instead it produces its surround effect entirely by the careful location and integration of speakers into its aluminium enclosure, and a well-designed passive crossover network.
The one metre wide speaker sits well, wall mounted under or over a plasma or LCD TV. Within, it contains three tweeters and seven bass/midrange drivers. These do not rely on bouncing sound from a back wall to create surround sound, but use phasing techniques to achieve the surround effect.
The only connections are the five sets of speaker inputs, which are real hi-fi style binding posts. There is no setup as such. You just plug the five outputs from a standard home theatre receiver into the binding posts, and play away. You don’t even need to adjust the speaker distances and volumes in the receiver’s setup menu. Just set all five speakers to ‘small’ and use a subwoofer.
A subwoofer is pretty much essential, because this system just doesn’t do anything approaching deep bass.
The sound quality was really, really good on both stereo music and movies. There was no sense at all of any kind of processing going on. Instead it just produced the goods.
Subject to one thing: having plenty of power on tap. The SurroundBar is quite robust, and not very efficient, so the more power you can supply the better. With a couple of hundred watts available for each channel, it was able to produce very high sound levels.
The surround effect with the vocal test track was rather unconvincing, but in contrast the performance with surround material in actual movies was excellent. Incredibly so, with a fully enveloping sound field the produced sounds up high, to the rear and sides, as though a set of five real loudspeakers were in place.