Напольная акустика — Oswalds Mill Audio AC1 Anniversary Edition

The AC1 Anniversary Edition is a limited-edition three-way floorstanding horn loudspeaker from Oswalds Mill Audio, marking the 15th anniversary of the model that started the company - the AC1 was OMA's very first loudspeaker, originally commissioned by photographer and filmmaker Anton Corbijn, who challenged founder Jonathan Weiss to build a speaker like no other. This special edition adds copper stands and cast bronze horn throats to the standard walnut construction, following a similar celebratory edition released at the brand's 10th anniversary.

Key specs that matter

Sensitivity is an exceptionally high 100dB per watt at 1 metre, with a docile impedance easy for even low-powered single-ended triode tube amplifiers to drive comfortably. The three-way design is constructed entirely from solid Pennsylvania hardwood - 1-inch thick walnut for this Anniversary Edition - completely hand-built and hand-finished with oil and wax using the same joinery construction found in the finest furniture, a build process taking roughly one month per pair. Bass comes from an efficient 15-inch Alnico paper-cone woofer, front-ported. The midrange uses a very special vintage compression driver originally made by RCA for actual movie theatre sound systems from the late 1940s through early 1960s, mounted to OMA's own conical 300Hz horn crafted from the same hardwoods as the bass enclosure - because this specific vintage driver exists only in finite quantity, standard AC1 production is limited to just 25 pairs, with the Anniversary Edition an even more exclusive variant. The tweeter uses what OMA describes as the most high-tech, best-engineered ribbon design ever made, itself horn-loaded for genuine coherence with the midrange and bass sections. OMA is the only current high-end audio manufacturer producing conical-profile horn loudspeakers, directly inspired by RCA's horn-loaded designs from the 1930s and 1940s.

Sound and use context

Expect a speaker capable of removing itself from the room despite its towering size and attention-grabbing looks - the vintage RCA driver and horn-loaded ribbon tweeter contributing standout midrange performance compared with even OMA's other current models.

Pairing

The exceptional 100dB sensitivity and docile impedance mean even a modest low-power tube amplifier, including single-ended triode designs, drives this speaker with genuine ease, and performance is best in medium to large rooms given the speaker's considerable scale.

Alternatives

Oswalds Mill Audio's Monarch offers a related but somewhat different horn-loaded design within the brand's catalogue, worth comparing directly with the company given both the standard AC1's already limited 25-pair production run and this Anniversary Edition's even greater exclusivity and considerable investment.