Reviewer: Srajan Ebaen
Financial interests: click here
Sources: 27" iMac with 5K Retina display, 4GHz quad-core engine with 4.4GHz turbo boost, 3TB Fusion Drive, 16GB SDRAM, OSX Yosemite, PureMusic 3.01, Tidal & Qobuz lossless streaming, COS Engineering D1, AURALiC Vega, Aqua Hifi La Scala MkII, Fore Audio DAISy 1, Apple iPod Classic 160GB (AIFF), Astell& Kern AK100 modified by Red Wine Audio, Cambridge Audio iD100, Pro-Ject Dock Box S Digital, Pure i20, Questyle QP1R
Preamplifier: Nagra Jazz, Esoteric C-03, Vinnie Rossi LIO (AVC module), COS Engineering D1, Wyred4Sound STP-SE Stage II
Power & integrated amplifiers: Pass Labs XA30.8; FirstWatt SIT1, F5, F6, F7; Crayon Audio CFA-1.2; Goldmund Job 225; Aura Note Premier; Wyred4Sound mINT; AURALiC Merak [on loan], Nord Acoustics One SE Up NC500MB
Loudspeakers: Albedo Audio Aptica; EnigmAcoustics Mythology 1; Sounddeco Sigma 2; soundkaos Wave 40; Boenicke Audio W5se; Zu Audio Druid V & Submission; German Physiks HRS-120; Eversound Essence, Rethm Bhaava [on loan]
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]; Sablon Audio Petit Corona power cords [on loan], Black Cat Cable red level Lupo
Power delivery: Vibex Granada/Alhambra on all components, 5m cords to amp/s + sub
Equipment rack: Artesania Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc Krion and glass amp stands [on loan]
Sundry accessories: Acoustic System resonators
Room: Rectangular 5.5 x 15 metres with double-high gabled ceiling and stone-over-concrete flooring
Review component retail: TBA


My 2016 Retrospective
talked of welcome trends: "The Rethm Bhaava released this year was an example of an actively augmented widebander. In a nutshell, that's a crossover-less driver spanning bandwidth from about the midbass on up to the treble. It is then supplemented by a self-powered bass system. Zu's Definition MkIV belongs to this breed as does Voxativ's 9.87 Pi and their soon-to-come Zeth II, a small single-driver floorstander which for 2017 shall sprout a powered 10" woofer addition. All four current Rethm models already pursue this path. I understand that Czechia's RDacoustics are presently at work on their own variation. Why is that a good trend? First, so-called widebanders, even those augmented by tweeters above 6'000-12'000Hz, eliminate a xover in the vital midband, hence associated phase shift. Second, with the vast majority of the audible range reproduced by one driver, one exploits very practical point-source benefits. Third, widebanders tend to work in the 94-100dB sensitivity range. This welcomes amplifiers of simple circuits and low power and tends to an early wakeup call on the SPL meter, i.e. works better at already low volumes. Fourth, the addition of active bass completes the bandwidth for modern music without requiring colossal rear horns. Such speakers can be smaller, hence cosmetically friendlier. Then they can add various bass adjustments to suit different placement/rooms. The morph from purist single-driver speaker to far more practical actively augmented widebander transforms a vintage fringe genre into a far more relevant buyer choice. It also enforces a certain creativity from their designers since bolting a standard low-efficiency massive rubber-roll-surround subwoofer to a far more efficient widebander is no guarantee for a happy ending without discontinuity and seams. Rethm with their isobaric bass systems and Voxativ with their dipole 99dB subwoofer demonstrate such creativity to contribute meaningfully to our hifi arts. Here's to more examples of this breed in 2017."


Unlike many in this specialty sector who drive stock because they lack resources to do otherwise, Voxativ design and craft their own high-efficiency wide-bandwidth drivers. Hence their smallest monitor gets a special 5er shrunk down from their core 8" platform which comes in a variety of Ferrite, Neodymium, field coil and hybrid motors and with paper or veneered wood membranes. The Zeth sports their standard 8-incher in either entry-level 1.6 or 2.6 version to designate Ferrite or Neodymium magnets respectively. The stock cone is paper but an upgrade to veneer is available. In an email, company chief Holger Adler reported that unlike hardcore widebander aficionados, the majority of users expect single-driver speakers to work like standard boxes. They give little to no thought about setup and ancillary requirements. "Plonk 'em down, fire up that receiver and off you go is the idea." It's not potentially lethal like handing Ferrari keys over to a 16-year old. After all, bad sound won't kill you. Still, it can be deadly for business. People will quickly blame the speaker—for sounding too lean, bass shy, forward or whatever—when in fact, they overlooked or misunderstood basics to get it to work as intended.


What to do when your product demands more? Dumb it down for mass consumption? If you're Holger Adler, you make it more universal. How? You already own splendid review and trade show feedback on your 9.87 Pi system with isobaric dipole woofer system. Whilst that high-efficiency solution could be easily tacked onto to the Zeth—one sub would be sufficient as shown above—for most it'd be cosmetically and financially a size or two too large. This segues logically into 2017 where the 12Ω Zeth with its short plinth-reflected rear horn and test winnings from Germany's Audio magazine was to get a downfiring active woofer. "We never had any complaints with the 9.87 system lacking bass or fullness even in large rooms. It made sense to integrate a similar solution into our smallest floorstander."

Voxativ at the 2016 Warsaw show.

Polish contributor Dawid Grzyb, for his own website StereoKnights, already reported on Zeth as the original purist widebander without woofer. He'd heard it at their annual fall show in Warsaw to be smitten with their sound. To retrieve the same enthusiasm inside his own four walls took him on a bit of a journey. It had primarily to do with securing valve amps from Amare Musica and Eggshell to overcome deficiencies when playing the speaker with his various solid-state amps. Given that Voxativ would entrust me with their activated Zeth despite my exclusive transistor harem already tells us something about being more universal. "We are again working with a high-efficiency woofer. Its moving mass is very important to meet the speed of the widebander. In this version we will use a class D amp to keep pricing low and only one woofer per side. The punch is wonderful. We gain 10dB at 45Hz. That's nearly 4 times louder than without woofer so the sound body is huge now. Extension is -3dB at 20Hz. It's all adjustable so there will never be any room problem. And if you don't want big bass, switch it off and use the widebander fullrange with your 2wpc tube amp. I will reserve the first serial pair for you to test." Soon coming to a theatre near you?