Unlike most planar speakers, the LO is not a di-pole, the tightly packed magnetic channels behind the diaphragm effectively creating an enclosed but vented rear chamber. Of course, the ‘voice-coil’ sits in free air, an arrangement that, combined with being more than 50m in length, effectively eliminates thermal compression. The diaphragm itself is formed from a light, rigid, fibre mat, with the bracing struts and stand-offs hand-constructed from more than 1000 of the 2700 discrete parts that a single LO speaker contains. In fact, the entire speaker is hand assembled and exactingly tuned in France by Patrick Marchandot and his team, a process that takes more than 200 hours for each unit.
That all stands true. What’s changed is that PureLow has produced a (slightly) smaller and (somewhat) more domestically acceptable model, in the shape of the GR – or Golden Ratio. With efficiency and bandwidth to burn, the company has kept the same construction but shrunk the height of the driver/panel. The GR stands a shade under 100cm tall, with the same 125cm width, The fully driven diaphragm is approximately 100cm wide and 74cm tall. That might not sound like much of a reduction. It doesn’t for instance, reduce the height of the subwoofer below window sill level. But it does have a significant affect on the overall visual impact of the unit(s). Having got used to two of the LOs stood at the far end of the listening room, the GRs are far more discrete and less intrusive. In part, that’s down to the other big, visual change. Where the LOs used a heavily radiused solid timber frame, the GR has a sharped edged profile, its frame painted in a high gloss finish – black in the case of the review pair. Colour can be specified, as can the choice of gloss or satin finish, making the GR far more visually compatible with the vast majority of modern, high-end loudspeakers. Their price is ‘compatible’ too. Starting at €40,000 each, one thing the PureLow GR isn’t is cheap- but then the best rarely is!
Electrically speaking, the GR has similar overall characteristics to the original model, with 90dB sensitivity, similar bandwidth and a slight reduction in impedance, to 3Ω, although once again, that’s almost ruler flat through the GR’s pass-band, making it an ideal amplifier load. The wide, curved base that supports the woofer panel now stands on four adjustable feet (the review pair only has two feet on the rear edge), giving some control over the panel’s attitude, although I’d like to see a far easier and a far greater range of adjustment. In particular, I suspect that the ability to raise the whole unit relative to the floor could prove an absolute boon when setting up. What I know is that in my room/system, the speakers required a small degree of rear rake and a touch of toe in to sound their best. That has the effect of ensuring that the panels are not parallel to any of the walls/boundaries. In my room it works best if the panels are raked and toed to precisely the same degree, but that might vary with circumstances. Likewise, I didn’t try a single panel to establish the preferred attitude for that.
Practical magic…
I drove the GRs from a single CH Precision A1.5, fed from the Wilson Active XO, with the main speakers bi-amped with M1.1s. ‘Satellites’ included the Peak El Diablo, Stenheim A5s and U2s and the Clarisys Minuets. None of them are speakers you’d think would need subs. But past experience has shown that even if a speaker doesn’t need subs, it doesn’t mean it won’t benefit from them. Hence Wilson’s provision of subs for the WAMM MC and XVX. I also used the GRs with the diminutive Vienna Acioustics Haydns – which was a hoot. Given that the PureLows look nothing like most peoples’ idea of a subwoofer, the sheer scale and weight generated by these tiny, free-standing, stand-mounts had many a visitor looking distinctly perplexed.
