Floor Loudspeaker Reviews

Doug White, of Philadelphia-area retailer The Voice That Is, has been a fixture at US audio shows the past few years, where he always gets great sound using loudspeakers from Tidal Audio. (There is no connection between the German audio manufacturer and the music-streaming service owned by Jay Z and Sprint.) In early 2017, Herb Reichert, Jana Dagdagan, and I visited White and spent a delightful afternoon listening to Tidal's then-new Akira loudspeakers. I promised myself to review the Akira, which costs a wallet-straining $215,000/pair, when my schedule opened up. As things turned out, it was more than a year before that opportunity presented itself.

The Akira . . .
. . . is an imposing yet elegant-looking tower standing almost 5' high on its bases, and finished in a high-gloss black lacquer. As I saw when Doug White removed two of the passive radiators to replace a tweeter (see later), this polyester-based finish is three millimeters thick; in fact, Tidal founder and CEO Jörn Janczak told me, when he visited my listening room, that, before sanding and polishing, the several coats together weigh more than 80 lb! The extensively braced enclosure itself is constructed from 42mm-thick boards of a proprietary polyshell material Tidal calls TIRALIT Ultra, which combines glass-hard layers with softer, damping layers of MDF and HDF, the 13 layers compressed with what Janczak describes as "tons of pressure and a layer-melting resin."

All drive-units are made by Accuton, exclusively for Tidal. The three 7.5" woofers are mounted vertically in-line on the front baffle, each clamped from behind with a ring of polished stainless steel. Their convex diaphragms are made from aluminum honeycomb, and while the response of the topmost driver extends sufficiently high in frequency to be crossed over to the midrange unit at about 250Hz, the middle driver rolls off a little earlier, and the bottom unit even earlier.

Above the woofers, the 5" midrange unit and 1.2" tweeter are mounted in a 1"-thick block of polished stainless steel, this decoupled from the enclosure with a cork gasket. The midrange unit is a bit special—its diaphragm is made of pure diamond, vapor-deposited on a substrate. Janczak told me that it takes four weeks of the chemical-vapor-deposition (CVD) reactor running 24/7 to produce two midrange diaphragms. As well as having good heat dissipation, diamond has both low density and high stiffness, meaning that the midrange unit behaves in pure pistonic manner up to a claimed 16kHz, a frequency far above the 2.2kHz crossover to the tweeter. An underhung 3" titanium voice-coil former is glued behind the 13-carat diaphragm; the midrange diaphragm is claimed to have a maximum peak–peak excursion of 7mm. The midrange unit's basket is milled from an aluminum block, and the magnet presents almost no obstruction to the diaphragm's rear wave. The tweeter, too, has a CVD diamond diaphragm, this one in the shape of an inverted dome.

Mounted vertically in-line on the Akira's rear panel are five passive radiators, these basically similar to the woofers but without motor systems, of course. The massive crossover—it weighs 44 lb—is mounted inside a hermetically sealed enclosure below the radiators. It offers "close to 12dB/octave" slopes, and features massive silver- and copper-foil capacitors and very-low-resistance inductors. (A custom-made 16mH inductor is said to have a series resistance of just 0.03 ohm.) Only close-tolerance Mundorf and Duelund parts are used in the crossover—and these are expensive. Janczak told me that for what Tidal pays for the parts used in the crossovers for a pair of Akiras, "you could buy a decent motorcycle."

A pair of custom-made silver binding posts at the base of the speaker completes the picture, along with three toggle switches that can be used in conjunction with a third binding post to reference the crossover circuitry to the system ground. I didn't try this, however.

As expensive as the Akira is, it is actually a scaled-down development of Tidal's flagship loudspeaker, La Assoluta, which Janczak described to me as "a pretty huge, 1100-lb tour de force" that costs $550,000/pair. The goal, he said, was to design "something ultimate but with modest dimensions." Modest? Only in comparison with La Assoluta!

Setup
Doug White and Jörn Janczak visited just after Independence Day to unpack the Akiras from their massive wheeled flight cases and set them up in my room. It turned out that these samples were the same speakers I'd heard in Philadelphia, and are White's own pair.

Once the speakers had been unpacked and their aluminum bottom plates fitted to the massive stainless-steel bases—easier to write than to do with these bulky, heavy speakers—White and Janczak painstakingly maneuvered them, inch by inch, until the low-frequency balance, midrange tonality, and precision of stereo imaging were to their liking. Interestingly, the Akiras ended up close to the spots in my room that Wilson Audio's Peter McGrath had found optimal for the Wilson Alexia Series 2 speakers I reviewed in July. The right Akira's woofers were 65" from the books that line the closest sidewall, the left Akira's woofers 35" from the LPs that line its sidewall. Both speakers were 77" from the wall behind them and 127" from my listening position.

Happy with these placements, White and Janczak then fitted the four feet under each base, each foot coupled to its base with a ball bearing. They bade me farewell and hit the road back to Philadelphia.

Listening
As always, I began my critical listening to the Akiras with the test signals I'd created for Editor's Choice (CD, Stereophile STPH016-2). The 1/3-octave bass-warble tones were produced with good weight down to the 50Hz band, with the 160Hz band higher in level, and the 100 and 80Hz warble tones a little lower in level than the bands to either side of them. As is usually the case, the 32Hz warble tone was exaggerated by the lowest mode in my room, but at my typical listening level, the 25 and 20Hz bands were inaudible. Overall, the lowest-frequency warble tones sounded extremely clean, with no audible distortion. The half-step–spaced tonebursts on Editor's Choice spoke clearly down to their 32Hz lower limit, but with less energy in the upper bass than I was anticipating, and a slight emphasis around 1kHz.

The dual-mono pink-noise track from Editor's Choice sounded smooth and evenly balanced as long as I sat upright in my listening chair, which placed my ears 39" above the floor. If I stood, which put my ears above the tweeter axis, the sound was free from any hollow-sounding coloration, as is so often the case, but the top octaves sounded slightly elevated, which isn't. The central image of the noise signal was narrow and stable, with no splashing to the sides at any frequencies.

Although, if I had to swear to it on the very first issue of Stereophile, I would admit that the Akira has a faint trace of character in the upper midrange, a little bit of extra "ping," voices sounded remarkably uncolored. I can't remember where I got the file, but a favorite recording of a woman's voice is Alanis Morissette singing her "You Oughta Know" live, accompanied by only an acoustic guitar, on The Howard Stern Show, in 2015. Despite it being a low-bit-rate (128kbps) MP3 file, this recording sounds extremely natural. Through the Akiras driven by Lamm monoblocks, Morissette was powerfully present in my room. I'm not sure that was necessarily a good thing, given the passive-aggressive nature of the song's lyrics, but her every little vocal inflection was laid bare by the Tidals, with no unnatural emphasis.

Nor did the Akira excel only with women's voices. In 2014, I recorded the Portland State Chamber Choir performing Henry Purcell's setting of Psalm 102, "O hear my Prayer," released on the CD Into Unknown Worlds (CD Baby). I listened to the 24-bit/88.2kHz master WAV file for this recording: It begins with unison altos on middle C, sequentially joined by first tenors, first basses, second altos, first and second sopranos, second tenors, and second basses. When the first basses enter in measure 11 with a rising C-minor scale on the words "And let my crying," your heart lifts as the minor key is transformed into major. Not only did the Tidal speakers present each of the eight vocal lines separately, but their superbly precise stereo imaging in both the width and depth planes let me fully appreciate their ensemble singing in that beautiful church acoustic.

The sheer resolution of the Akiras continued to astonish me throughout my auditioning. An album I hadn't played in a while was Winging It: Piano Music of John Corigliano (CD, Cedille CDR 90000123), performed by Ursula Oppens and Jerome Lowenthal. Roon suggested I listen to Chiaroscuro for 2 Pianos Tuned a Quarter-Tone Apart, (24/44.1 FLAC file). One piano echoes the other, the uncertainty in pitch lending an addictively haunting quality—through less-resolving speakers, I'm sure this recording would merely sound as if the pianos hadn't been tuned. And the thunderous bass chords indeed sounded . . . thunderous.