Reviewer: Srajan Ebaen
Financial interests: click here
Sources: 2TB iMac 27" quad-core w. 16GB RAM running OWS 10.8.2, PureMusic 2.02, Audirvana 1.5.10, COS Engineering D1, Metrum Hex, AURALiC Vega, Aqua Hifi La Voce S2, SOtM dX-USB HD w. super-clock upgrade & mBPS-d2s, Apple iPod Classic 160GB (AIFF), Astell& Kern AK100 modified by Red Wine Audio, Cambridge Audio iD100, Pro-Ject Dock Box S Digital, Pure i20
Preamplifier: Nagra Jazz, Esoteric C-03, Bent Audio Tap-X, COS Engineering D1
Power & integrated amplifiers: Pass Labs XA-30.8; FirstWatt S1, F6; Crayon Audio CFA-1.2; Goldmund Job 225; Gato Audio DIA-250; Aura Note Premier; Wyred4Sound mINT; AURALiC Merak [on loan]; Job Sys 250 monos [on review]
Loudspeakers: Albedo Audio Aptica; soundkaos Wave 40; Boenicke Audio W5se; Zu Audio Submission; German Physiks HRS-120, Gallo Strada II w. TR-3D subwoofer
Cables: Complete loom of Zu Event; KingRex uArt, Zu and LightHarmonic LightSpeed double-header USB cables; Tombo Trøn S/PDIF; van den Hul AES/EBU; AudioQuest Diamond glass-fibre Toslink; Arkana Research XLR/RCA and speaker cables [on loan]
Power delivery: Vibex Granada/Alhambra on all components, GigaWatt PF-2 on amps
Equipment rack: Artesania Audio Exoteryc double-wide 3-tier with optional glass shelves, Rajasthani hardwood rack for amps
Sundry accessories: Acoustic System resonators
Room: Irregularly shaped 9.5 x 10m open floor plan with additional 2nd-floor loft; wood-paneled sloping ceiling; parquet flooring; lots of non-parallel surfaces (pictorial tour here)
Review component retail: €23'900 - €25'600/pr depending on finish

When it comes to bending-wave drivers, Germany has its autobahn still without speed limit. From the Manger to the Göbel to the German Physiks, the country's speaker market thrives on an unusually high variety of these exotic transducers. Yet they're very dissimilar. The Manger is a direct radiator, the Göbel is an open-backed dipole panel. The German Physiks takes a Göbel-type film membrane, then turns it into an upside-down funnel to work as a direct-radiating omni à la Ohm Walsh. Here it overlaps with two other radical German omni drivers - the mbl Radialstrahler and the Elac 4pi Plus.2. Yet neither of those is a widebander. The Elac is a circular super tweeter based on a HF ribbon. The mbl requires different sizes to cover limited bandwidths like standard dynamics do. Here German Physiks overlap with Göbel again. Benders from either company cover from the mid 100Hz to the limits of human hearing to eliminate crossovers anywhere near the presence region plus associated phase shift and dispersion discontinuities between multiple drivers.

What's the deal with omnipolar dispersion*? Lack of imbalanced power response is what. Traditional direct radiators suffer narrowing dispersion with rising frequencies. Bass and mid frequencies propagate 4pi or in full space to freely reflect off boundaries for so-called room gain. Higher frequencies suffer progressively narrowing dispersion called beaming. They gain far less room boost from reflections. Think flood light versus spot light. This imbalances the sound. Clearly beaming is an unnatural hifi artifact. Whether you hear an orchestra from the front or the cheap student seats in the back, tonal balance doesn't change. A violin sounds the same from the front, sides and back. That's not the case for normal speakers. Only omnis—and to a lesser extent bi/dipoles and speakers with rear, side or upfiring drivers—mimic natural sound propagation. A violin also doesn't scramble its bandwidth through a crossover. Nearly all speakers must however.

A single driver for the entire bandwidth with proper dynamics and linearity is still mythical though Voxativ & Co. disagree. Mating 360° direct radiation to 7+ octaves makes the German Physiks unique. Hence it's used in all their models. Just as you can in a live concert where moving from a center to side seat won't change tonal balance or much affect soundstaging, so a German Physiks offers a very wide sweet spread. Serious listening no longer is an asocial pursuit of one. If you're sour on a narrow sweet spot, the Borderland is for you. If you're tired of tonal bleach, it is too. By deliberately playing the room equally from top to bottom because its omni widebander hands over to an omni downfiring 12" woofer, it creates more ambient-rich sound. That's precisely what sound engineers do to thin lean voices. They add reverb to inject venue sound. In very natural fashion, the Borderland speaker is a reverb generator. Of course in an anechoic room all of that goes away. This particular action depends on reflective boundaries. Hence the degree of reflectivity vs. absorption of your room affects how much or little you'll harvest. Balance is key. An overly reverberant space like a church smears complex music. Individual tones linger to overlay those which follow. Particularly rapid short notes like arpeggios turn into standing chords. That's like playing a piano with its damper pedal disengaged.

* Canadian Muraudio have another entry into this sector with an omni hybrid electrostat which combines a faceted array of curved stat panels on top with three woofers oriented at 120° each around the lower circumference. In many ways their Domain Omni PX1 is the electrostatic cousin to the HRS-120/Borderline concept.

With proper distance from the wall, what this speaker does is rather more subtle. In standard living rooms filled with furniture, carpets, curtains and such, being too echo-y really isn't an issue. Room sound as mined deliberately by an omni simply acts as a tonal enhancer. It'll very rarely become an outright blurring agent. But it will always operate on the far side of listeners who pursue a very dry extremely separated-out sound such as you'd want and get in a nearfield monitor setup. If you cherish textural redolence, an omni has your name on it. If you want maximal crispness and focus, it does not. Proper 4pi radiation in the high frequencies can obviously present a different tonal balance than the one you're used to with the usual beaming tweeters. Hence German Physiks offer a response adjustment between 8-12kHz from -2dB to +4dB in four equal steps via a jumper above the rear-mounted biwire terminals. This lets owners determine the relative HF amplitude contingent on taste and how absorptive or reflective their room behaves. Against this backdrop, we can now discuss the Borderland model in more detail. It's a 2-way speaker with a low filter point of 190Hz for a response of 28 - 24'000Hz with a minimum impedance of 3.7Ω @ 375Hz. Efficiency is a lowish 86dB though omni radiation adds about 3dB to the actual in-room spec. Weight is a still manageable 54kg and size a rather compact 40.4 x 40.4cm footprint with 1.23m height. The hexagonal cross section makes for narrower stiffer vertical panels than the ubiquitous rectangular cross section and the structure is additionally strengthened with cross braces, then lined with Hawaphon, a material which traps steel shot in synthetic cells. Integrated into the sealed bass section is a Helmholtz resonator tuned to cancel the primary organ-pipe resonance. The basic recipe is obvious. German Physiks need an inert 'dead' enclosure and quick well-damped bass system to not undermine the excellent impulse response of their unique 360° widebander on top. After all, this is a hybrid system. As is true for electrostats with cone woofers, their challenge is always to have the higher-mass conventional drivers keep up with the exotic lightweights. Hence the need for LF speed, ergo a sealed not ported alignment. The Borderland currently in its 4th iteration for a MkIV suffix is a scaled-up lookalike of the €11'500/pr HRS-120 which I reviewed previously and then purchased as the anchor for our upstairs 2-channel video system. But for our downstairs 'big room'—roughly 100m² of open floor plan listening room, kitchen, entry, office and corridor plus open loft—the Borderland is the designated driver on the omni widebander autobahn. Its bigger woofer and higher output capabilities promise more potent coverage.