Waterfall Iguascu

French firm Waterfall has actually been in existence for around ten years, though its first few years were apparently largely spent developing the concept of glass speakers to make them a practical possibility. The company now produces a full range of stereo and surround speakers, including its flagship Waterfall, the compact Athabasca, and there are also the flat Hurricane satellites and a (non-glass) subwoofer.

The Iguascu sits between the standmount Athabasca and the three-driver floorstanding Victoria. Despite their proliferation however, it seems there are plenty of reasons for not making speakers out of glass, which goes some way to explaining why Waterfall are the only people who do. Glass is an extremely dense material, which is good for lowering the possibility of resonance, but it can also be extremely difficult to work with.

For one thing, the fact that they're see-through cuts down your options for damping, until someone invents transparent foam perhaps. There is however a neat little foam square at the bottom of the cabinet, above the wide and thin, rear-firing bass port, which goes some way to effect this. Wiring has been cleverly incorporated into the design, with four cables stretched along the front of the cabinet producing a taut, guitar-string effect, rather than the usual untidy clutter. Incidentally, there is just a single pair of connections at the base - bi-wiring is not an option on this speaker.

Waterfall also has a neat little innovation behind the 150mm paper cone bass/mid driver in the shape of its ADT (Acoustic Damping Tube), essentially a foam pad at the end of a short tube which limits the return of the back wave on the driver.

The glass panels, joined with a specially developed glue which provides the necessary strength without adding any unwanted resonances, are 6mm thick - thinner than conventional MDF or wooden cabinets, though they end up weighing around about the same. The tweeter is a 20mm Neodymium dome with a short horn flare, protected behind a two-bar wire grille.

Virtually all of the problems inherent in glass speakers have been overcome by Waterfall, except for their fragility. The installation instructions warn of danger of "destruction" if they're allowed to fall. Aesthetically, they're prone to marking, especially from fingerprints. Perhaps not the best audio solution for households with young families then.

Sound
These speakers have been gathering a lot of attention in the print media, due in no small part to the way they look. Fortunately, the attention is generally justified sonically as well as visually. The 20mm 'Atohm' Neodymium dome tweeter in this second-generation version of the Iguascu has been upgraded, and now uses a new type of damping at the rear of its titanium vacuum-coated dome, which promises a more linear response than previously. It delivers impressively, producing a warts-and-all performance from the harmonica on Dylan's Bootleg Series - not pretty perhaps, but no doubt accurately reproduced. Likewise the snap and spark of the jangling guitars on the Go-Betweens' Bright Yellow, Bright Orange, were rendered with a well-rounded grace.

The single bass/mid driver (twinned on the more upmarket Victoria model) has its work cut out to offer a full-range performance in this uniquely designed speaker and for the most part it delivers well. Based on the T13 model by top French driver manufacturer Triangle (pronounced 'Tree-ongle', by the way), it's been adapted to incorporate Waterfall's proprietary rear damping system. It goes low, especially when backed up with a bit of close-wall placement. though perhaps doesn't deliver as precisely as some others in the low bass - it doesn't match the Focal-JMlab 726S in this department for example. Moving them out from the wall rewards with a greater degree of tautness, but the low end suffers - your choice will largely depend on your taste in music.

In the midrange however, the Iguascu is exceptionally crisp and revealing. Every buzz of the strings and shuffle in the studio from the one-take recording of Swedish jazz bass player Lars Danielsson's Suffering on his excellent Libera Me album was delivered consistently, even at fairly low volume. In fact, this speaker seems to deliver particularly well at low levels, offering exceptional clarity and insight, the pay-off being that this can appear a little strident when the volume is cranked up.

Stereo imaging is good, with the sound showing no temptation to linger around the speakers and there's no apparent tendency towards boxiness - perhaps because of the exceptional solidity of the structure, though more likely due to the degree of care that's been taken to get the balance of elements right with this unusual speaker.