Floorstanding loudspeakers — Avantgarde Acoustic UNO SD

The UNO SD is a fully active horn loudspeaker from Avantgarde Acoustic, a German manufacturer renowned for distinctive, large-scale horn-loaded designs combining exceptional efficiency with built-in amplification. The UNO SD represents a more compact entry point into Avantgarde's horn philosophy compared with the brand's largest models, while retaining the core engineering principles that define the company's entire catalogue.

Key specs that matter

Rated response is 290Hz to 22,000Hz within plus-or-minus 3dB - this notably high low-frequency figure reflects that the UNO SD's horn section handles only midrange and treble, with bass reproduction supplied by the built-in powered subwoofer section rather than the horn itself. Sensitivity is an extraordinary 107dB into an 18 ohm load - an exceptional efficiency figure reflecting horn loading's inherent advantage over conventional cone drivers, meaning even a modest amplifier drives this speaker to considerable volume with ease. Recommended external amplifier power is just 10-50W for the horn section, while built-in amplification totals 700W distributed across the design - 100W plus 100W for different horn-fed sections and 500W dedicated to the powered bass module. At 50.0 x 135.5 x 61.5cm and 81.5kg, the UNO SD's considerable weight reflects the substantial internal amplification and bass driver hardware packed into its horn-topped cabinet.

Sound and use context

Expect the immediate, effortless dynamics and speed horn loading is specifically prized for - the extraordinary 107dB sensitivity means the horn section responds with explosive transient speed even from tiny amounts of amplifier power, a sonic signature considerably different from conventional cone-and-dome loudspeaker designs.

Pairing

The horn section's low 10-50W recommended power range makes the UNO SD compatible with low-power tube amplifiers, including single-ended triode designs, while the substantial internal bass amplification handles low frequencies independently regardless of external amplifier choice.

Alternatives

Avantgarde Acoustic's larger Duo and Trio horn systems sit above this UNO SD at considerably greater scale and price, worth considering instead if this model's already distinctive horn character still leaves ambitions for Avantgarde's larger flagship designs. Avantgarde's decades of horn-loading expertise, refined across its entire product range from this compact UNO SD through to the towering Trio and flagship Trimo systems, is fully reflected in the careful integration between the horn section and its internal powered bass module.