The upper reaches of the rear panel are populated with either the bi-wired binding posts for passive connection (at the top) or the XLR input and dip-switches for the separately powered iTron active amplification and crossover. Those dip-switches allow adjustment of relative level between the mid and treble units, as well as the overall gain of the horns’ output relative to the bass section. And yes, you got that right: driven active, the Uno SD does require two separate power cords. In this case, signal connection would be made using a single XLR lead, normally connected to the bass amp and then, via the ‘daisy chain’ socket and a second XLR interconnect to the iTron section. The excellent outrigger feet that I first encountered on the Duo GT are included here, a welcome sight as they make the critical process of set-up significantly easier.
One thing that the Uno SD does share directly with the Trio G3 is its bass control system and software. When I reviewed the Trios, the Space Horns were software controlled with an incredibly complex programme that allowed remarkably precise adjustment at the expense of an impenetrable interface. That software has developed substantially in the intervening period and now operates on a dual-level basis – a clear and intuitive control panel for everyday use and users and a password protected level for professional installers with the training and measurement equipment required to use it without totally screwing things up. It’s a near perfect arrangement. Run one Ethernet cable between the speakers and a second to the laptop you’ll be using, open the Avantgarde software (downloaded from their website: there’s a Software tab in the Support section) and it will search for and connect to each of the bass sections on the network – whether that’s the two Unos or a quartet of Space Horns. Click on a bass unit and you get the control panel you’ll see in the pictures. You can adjust each of the speakers individually, or pair them so that adjustments are shared.
The control panel gives you the ability to adjust overall bass level, the crossover point and bass ‘tilt’, along with clear explanations as to what these functions do and what you should expect to hear. There are two 6dB/3dB notch filters that can be set for frequency (to help combat dominant room nodes) and an eight-band graphic equaliser – although it’s the three lowest bands at 30, 40 and 60Hz that are likely to prove most useful. Using these options along with the timed low-frequency sweep and discrete low-frequency tones on the Nordost test disc (to first identify key frequencies and then adjust or accommodate them) it was astonishingly easy to integrate and optimise the Unos’ bottom end. Sitting with the lap-top at the listening seat, at first I tried adjusting them as a pair, but ultimately it was easier and more productive to run and fine-tune each speaker in turn with a mono signal. Dialling in sub-woofers is a familiar and always demanding task. The Avantgarde software package made it considerably easier and more intuitive. Could taking things to the next level improve results? Quite possibly – especially in a difficult room. But I was astonished not only by how easy and effective the Avantgarde approach was, but the quality of the results achieved. It’s a perfect example of that old audio conundrum: building performance potential into a product is one thing; making it deliverable in the real world is quite another. When it comes to adjusting and integrating the bottom-end of their latest speakers, Avantgarde have pretty much nailed it.
