Floorstanding loudspeakers — German Physiks HRS-130

The HRS-130 is the entry-level floorstanding loudspeaker from German Physiks, the brand of DDD Manufactur GmbH, founded in 1992 and based in Frankfurt. It replaced the long-running HRS-120 and, like every German Physiks model up to the flagship Gaudi Mk III, it is built around the company's proprietary omnidirectional DDD driver, here mounted on top of a slim octagonal column with a downward-firing woofer in the base.

Key specs that matter

The HRS-130 combines one carbon-fibre DDD driver, covering 220Hz to 24kHz, with a 10-inch woofer firing downward in the base, the same bass unit used in the far more expensive PQS-402. Frequency response is 29Hz to 24kHz, sensitivity is 86.9dB and impedance is 4 ohms. Dual WBT nextgen terminal pairs are fitted for split feeds to the DDD and woofer sections. The speaker stands about 1.26m tall. Standard finishes are high-polish black or white polyester, with satin or high-polish veneer, paint and carbon-fibre options to special order. At launch it cost GBP 11,900 to 15,450 depending on finish.

Engineering and use context

The DDD driver is a cone of carbon fibre only 0.15mm thick, with a total moving mass of about 3.5g, and each one is hand-built in the German Physiks factory. It works as a wide-band transducer using a combination of pistonic, bending-wave and modal radiation, and its geometry makes it radiate omnidirectionally, spreading sound evenly around the speaker instead of beaming it forward. Because one driver covers everything above the woofer, there is no crossover anywhere in the midrange, and the driver is phase-linear across its working range. The DDD operates in free air with no enclosure behind it. The 10-inch woofer works in a sealed enclosure, and this is linked through a small opening to a smaller cavity at the top of the cabinet that acts as a Helmholtz resonator, tuned to the resonant frequency of the main bass enclosure to smooth the bass response. The HRS-130's cabinet is slightly taller than the HRS-120's, allowing a larger resonator and the move from an 8-inch to a 10-inch woofer. The crossover was developed from the one in the larger Borderland Mk IV. The woofer fires down and out through openings around the plinth.

Pairing

The HRS-130 is not an easy load, so it wants a capable amplifier, and German Physiks recommends at least 70W into 4 ohms. Because it radiates in all directions, it is less dependent on toe-in and precise listening position than conventional speakers, but room surfaces around it play a larger part.

Alternatives

German Physiks' own Borderland Mk IV uses the same DDD driver with a larger bass system in a bigger cabinet.