Trenner & Friedl Sun loudspeaker
With their unusually small dimensions and not-small price, you're probably wondering how two such speakers can fill a roomheck, a bookcasewith real-world frequency range, organic tone, credible bass extension, and lifelike dynamics. I wondered that too, the moment my eyes spotted the Suns' lovely birch cabinets in Greenwich Village hi-fi emporium In Living Stereo.
At first glance, the Sun reminded me of the Auratone 5C Super-Sound-Cube: a similarly small speaker that, from the 1970s through the '80s, was seen in professional recording studios from Albany to Anaheim. (Such albums as the Bee Gees' Saturday Night Fever soundtrack and Michael Jackson's Thriller were mixed using Auratoneswhich, I should add, some recording engineers referred to as "horrortones.") Andreas Friedl designed the Trenner & Friedl Sun as a small monitor speaker to use in his own recording studiobut this isn't 1980, and his Sun is no tricked-out Auratone. For one thing, with its sensitivity of 82dB and impedance of 4 ohms, this mighty mite is a bear to drive. And though the Sun's visual appeal is subtle and its finish is silky to the touch, its Cardas single-action binding posts accept only spade-terminated speaker cables. Boo-hoo!
Loudspeakers with coaxial drive-unitsthe commonest examples of which have separate woofer and tweeter diaphragms, the latter positioned either at the front or rear of the former's pole-pieceseem to come back into fashion every decade or so. The 1940s saw the predominance of the Altec 604 driver. Tannoy's Dual Concentric design gained popularity in the 1950s. The Altec 604 rose again in UREI's 813 studio monitor of the 1980s. More recently, KEF introduced the UniQ; Cabasse came up with its four-way concentric QC-55 driver; and Andrew Jones got his mojo seriously working with the concentric driver of the Elac Uni-Fi UB5. I wanted to know: have Trenner & Friedl brought a new big bang to the coax party?
Trenner & Friedl's loudspeakers are hand-built in the mountainous, forested countryside of Styria, Austria, with final assembly near Styria's capital, Graz. Austria is home to some of the finest luthiers in the world; woodworking and music are in their blood. Peter Trenner and Andreas Friedl have designed and developed a line of seven speaker modelsfrom the entry-level Sun to the mid-tier, floorstanding Pharaoh ($13,000/pair), to their top model, the Duke ($175,000/pair)all made almost entirely of natural hardwoods.
"Wherever possible, we use natural materials," states T&F's website. "Thus, we damp our loudspeakers with sheep's wool. We long ago ceased the use of endangered tropical hardwood veneers in favor of locally grown hardwoods for our cabinets. The surrounds of many of our drivers are made of cloth, which is extremely durable."
Sheep's-wool damping? Cloth surrounds? I genuinely admire this small company's organic approach to crafting music-reproducing machines. Further wisdom from the T&F site: "All of this not only serves to protect our Mother Earth, but also has sound technical foundations: our ears are extremely sensitive to the resonances that occur in artificial materials."
Perhaps this explains why I always haul ass away from giant-robot (thanks, Herb Reichert!) loudspeakers sporting metalflake finishes, beryllium tweeters, and ceramic woofers. Like my women, my coffee, and my hairstyles, I like my loudspeakers au naturel. Same as it ever was.
The Sun's coaxial driverthe SEAS L12RE/XFCconsists of a 1" silk-dome tweeter set into a 4.7" black-anodized aluminum mid/woofer coupled to a ferrite magnet 3.5" (90mm) in diameter and weighing 3.3 lbs (1.5kg). In the Sun enclosure, this two-way coaxial unit is ported to the rear via four very small, cute funnels that look as if some worker bee drilled them clear to China.
The advantages of a coaxial driver? Bob Clarke of Profundo, T&F's US distributor, gave me a lesson in electromechanics: "The difficulty with coaxial systems is to design them with no colorations; to locate the tweeter in exactly the right position, in order to have the same temporal point of origin as the woofer (time alignment); to harmonize the drivers; and to achieve focus of the whole, including the cabinet. Then, the coaxial principle has clear advantages: Ideal, point-source design that is independent of listening angle; [consistent] impulse behavior to produce the same sonic character: homogeneity. This sounds more natural and one doesn't need to spend so much time worrying about listening/mounting height/angle etc."
Clarke explained that the Sun's cabinet is dimensioned according to the golden ratio of 1:1.618 . . . , which, he claimed, "creates a more rigid box, reduces internal standing waves, and spreads out more evenly the resonant frequencies of the panels of the box, so that none 'stick out' to cause a tonal imbalance." (footnote 2)
After Trenner & Friedl had researched the resonant qualities of various ecologically sensitive materials, they chose to build the Sun's cabinet walls of birch ply of varying densities, to further reduce standing waves.
Clarke describes the Sun's crossover, handmade in Germany by Mundorf, as "employing Linkwitz-Riley functions with a very steep and flat 4th-order acoustic roll-off curve." According to T&F's website, Mundorf uses "premium Mundorf capacitors . . . baked-lacquer, flat copper coils with extremely low skin-effect, [and] metal-film resistors for purest reproduction of high-frequencies."
Systems and Setup
I evaluated the Trenner & Friedl Sun in two different systems. In both, the Suns were marginally toed in.
The system in my larger, 12' by 13' room comprises a Kuzma Stogi turntable with Stabi tonearm, a MacBook computer with PS Audio NuWave DAC, Shindo Laboratory Allegro preamplifier and Haut-Brion power amp, and AudioQuest Castle Rock speaker cables. I placed the Suns 14½" from the front wall and 7' 6" from my listening chair.
In my second, more tightly packed room (11' by 12'), I listened in the nearfield using a Music Hall MMF-7.3 turntable and arm, a Heed Quasar phono stage and Heed Elixir integrated amplifier, and Auditorium 23 speaker cables. Here the Suns sat 6" from the front wall and 5' 7" from my chair, each speaker on four small squares of mahogany to control ringing, atop a 24"-high steel stand from Bowers & Wilkins.
I feared that banana plugs sliding up against speaker posts designed for spades would be less than optimal. Soon, I requested and received a loaner set of Cardas banana-to-spade adapters ($60/four) from Dan Muzquiz of Blackbird Audio, near San Diego, California (www.blackbirdaudio.com). The difference wasn't subtle. The adapters opened the Sun's top end to reveal perhaps its most consistent trait: absolute transparency to the source.
Footnote 1: Merriam-Webster's Collegiate Dictionary, 11th Edition defines golden section, aka golden ratio, as "a proportion (as one involving a line divided into two segments or the length and width of a rectangle and their sum) in which the ratio of the whole to the larger part is the same as the ratio of the larger part to the smaller."
Footnote 2: As the Golden Ratio is either 1.618 or its reciprocal, 0.618, as the ratio of the Sun's height to its width is 1.3125, that of its height to its depth 1.5, and that of the width to the depth, 1.1, Trenner & Friedl's use of the Golden Ratio in its promotional literature is both incorrect and misleading.John Atkinson