The PureLow GR Subwoofer
By Roy Gregory
Subwoofers and discussions related to the importance of genuine low-frequency extension and output, are amongst the most misunderstood subjects in audio. Towards the end of the 20th Century, the subwoofer had almost ceased to exist as a product category – at least in Europe, with its smaller, more solidly constructed rooms. Products like the AudioPro subs kept the notion on life-support, although these were mainly crossover products from the professional field. Meanwhile, in the US, companies like Wilson and Entec kept the faith, supported by a market with bigger rooms and an appetite for ‘bigger’ speakers.
Then – two things happened…
The first was the advent of surround sound and home theatre/AV systems. The second was the widespread availability of and growing familiarity with DSP technology. The two collided in a noisy perfect storm of high-output, wide bandwidth excess. Home theatre systems demanded the extended low-frequencies only really available from subs: DSP equalisation delivered the means of extracting that output from smaller (more domestically acceptable) boxes, at lower (more domestically acceptable) prices, while offering the possibility of cramming those boxes into smaller spaces. Suddenly Subs were back on the audio agenda, prominent in audio stores and tempting audiophiles with the opportunity of adding low-frequency extension to modestly sized speakers for a modest financial outlay.
Unfortunately, it’s not as simple as it might seem. The AV market places a heavy emphasis on quantity rather than quality – after all, how many of us really know how explosions or train wrecks sound, save for the fact that they are undoubtedly LOUD! Meanwhile, the promise of powerful DSP comes, a bit like powerful drugs, with a number of unpleasant and potentially ruinous side-effects. Not least of these was the inherent latency involved in the processing itself, which messed with the timing of the low-frequencies, undermining musical and rhythmic coherence, turning the extra low-frequency energy from an advantage into an embarrassment. Herein lies the root of current audiophile scepticism when it comes to subs. Add to that the fact that most of the subwoofer systems you’ll hear will be poorly set up and that most subs are set with their levels too high (“What’s the point of having them if you can’t hear them?”) and it’s no surprise that poor integration and musical mud are the order of the day.
But it doesn’t have to be that way.
The problems outlined above relate directly to the misapplication of technology and misconceptions about the ease with which you can add extended bass to an audio system. Despite the fact that equipment for AV and stereo/music replay purposes is superficially similar – both systems employ amps and speakers and play digitally stored material – it’s a bit like assuming that a delivery truck and a sports car are the same, because they both have four wheels and an engine. Approach the problem from the perspective of an existing, two-channel set-up and the situation starts to look very different.
