Trenner & Friedl Sun loudspeaker

The Trenner & Friedl Sun ($3450/pair) is arguably the smallest stand-mounted loudspeaker presently available for serious home listening: only 8.5″ high by 6.25″ wide by 5.5″ deep and weighing just 7.5 lbs. The Sun is the entry-level model from this Austrian loudspeaker manufacturer, and its ported, solid-birch cabinet is designed and built to golden-ratio proportions (footnote 1) It has a single, coaxial driver from SEAS and a crossover made by Mundorf. The Sun boasts a frequency response of 55Hz–25kHz, +0/–3dB; friends of mine have heard the speaker plumb remarkable depths when paired with the right amplifier. And though they’re barely bigger than a pair of Audeze LCD-4 planar-magnetic headphones, the Suns do play louder!With their unusually small dimensions and not-small price, you’re probably wondering how two such speakers can fill a room—heck, a bookcase—with 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.

The Sun reminded me of the Auratone 5C Super-Sound-Cube when I have first sight at it: 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 Auratones—which, 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 studio—but 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!

Here are coaxial drive-units with the loudspeakers —the commonest examples of which have separate woofer and tweeter diaphragms, the latter positioned either at the front or rear of the former’s pole-piece—seem 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 Sun loudspeaker

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 models—from 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 driver—the SEAS L12RE/XFC—consists 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.

Trenner & Friedl Sun loudspeaker

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.”

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 ( 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.

Bob Clarke had noted that the Suns “start to get fun at about 50Wpc. Beyond that, the more [power] the better, given equal sound quality of the amps.” My Shindo Haut-Brion puts out a maximum of 22Wpc. How would the Suns fare with a lower-than-optimal amount of power?Listening: Kuzma, PS Audio, Shindo
Could these little wonders go deep with few watts to spare? Yes and no. The Trenner & Friedl Suns cleanly produced bass notes of substance when present on the recording, and with apparently fewer watts than Clarke had said they needed. Time after time, playing everything from New Orleans funk to UK electronica to Black Saint jazz, I was surprised. It was back to that transparency thing: For better or worse, the Suns unshuttered a consistently clear window on the source. When I played well-recorded music, they treated me to ample bass reproduction, as well as terrific drive, clarity, refined textures, true tone, and—if not forced to reproduce Tchaikovsky’s 1812 Overture—dynamics.For shoots and giggles, I played the 1973 hit “Frankenstein,” from the Edgar Winter Group’s They Only Come Out at Night (LP, Epic KE 31584). The Suns projected the visceral burn of Winter’s spiraling Moog synthesizer with gleeful riotousness. Even more of a Karloff–ian kick in the head was the recording’s heavy-duty bottom end: Hammond B3 organ, electric bass, booming bass drum, and boisterous Afro-Cuban percussion, all creating a rich, thick magic carpet of groove goodness via the Suns. The Trenner & Friedls parlayed the top end, particularly the midrange, with silky ease and smoothness, and their fat bottom was exactly that: oily, wide, heavy rolling.Do I exaggerate? I do not.

Next, I played The Singers Unlimited’s Invitation (LP, MPS MC22016), a collection of songs beautifully harmonized for vocal quartet, and accompanied by accordionist Art Van Damme, double bassist Eberhard Weber, and drummer Charly Antolini. The Suns sorted out the music’s layered vocal harmonies and jazz accordion with sweet vanilla soul, and rendered Weber’s tactile bass notes with coherence and drive, from the uppermost frequency to the lowest whirr. Weber’s bass lines were easier to follow through the Suns than through many larger speakers. Via the Suns, I never felt I was missing anything that’s on this charming LP.

Trenner & Friedl Sun loudspeaker

I got my biggest thrill when I dropped on the Kuzma’s platter Eddie Bo’s “If It’s Good to You (It’s Good for You),” from New Orleans Funk—New Orleans: The Original Sound of Funk, Volume 2 (4 LPs, Soul Jazz SJR185). I also got a hint of the Sun’s limitations. This righteous, four-LP slab of seminal New Orleans funk was remastered by Soul Jazz Records, a consummate UK label delivering first-rate reissues of soul, jazz, funk, dub, and reggae. “If It’s Good to You” is all grind and grimace, delivered primarily by Mr. Bo and the Meters’ illustrious drummer, Zigaboo Modeliste. The Suns devoured Bo’s New Orleans funk, but when I played it loudly, the speakers’ little drivers chuffed and huffed; I could hear them breaking up as I turned the Shindo Allegro’s dual volume knobs up to midpoint, a place they’d never been before. Though the Suns mightily rocked and rolled with Mr. Bo, their magic didn’t extend beyond the plane described by the speakers’ baffles. They imaged beautifully and “disappeared,” but the generally flat soundstage, and the anemic, hollow sound, even when plumbing the bass depths, made it clear that with such hardballing material they cried out for more power than the Haut-Brion could deliver.

Listening with the Music Hall and Heed
The combination of Trenner & Friedl Suns with the Heed Elixir integrated amplifier—one of today’s most remarkable audio bargains—was a match made in hi-fi heaven. The Heed provided more wallop than my Shindo amp could muster: 50Wpc into 8 ohms, or 65Wpc into the Sun’s 4 ohms.

But first, I pulled out John Atkinson’s Stereophile Editor’s Choice Sampler & Test CD (16-bit/44.1kHz FLAC, Stereophile STPH016-2), specifically track 21, “Bass Decade Warble Tones.” Each tone in this series is lower in frequency than the one before: 200, 160, 125, 100, 80, 63, 50, 40, 31.5, 25, and 20Hz. The Suns played the 50Hz tone cleanly and strongly, and valiantly maintained their force at 40Hz. That speaks for itself.

The combo of Music Hall turntable, Heed integrated, and T&F Suns was one of those golden matchups in which everything fell perfectly into place and synergy was achieved. I listened for hours on end, exploring my collection anew. Whether spinning vinyl from French electronic duo Air, 1970s jazz titans Old and New Dreams, Eddie Bo, or even Georg Solti conducting Bart¢k, these products’ simpatico strengths were in full effect, record after record.

Air’s four-track Casanova 70 (12″ EP, Parlophone 0724389365757) was reissued on Record Store Day 2016. A gossamer production, it’s an electronic lullaby of cosmopolitan easy listening with a sardonic edge. Harps glide and pulsate, and electric-bass notes cross good vibrations with a Fender Rhodes piano worthy of Barry White and a swooning string synth. This slo-mo groove spree let me marvel at the Sun’s consistently rich tonal palette and spot-on rendering of textures. When a shrill Hammond B3 appears midway through the title track, the Suns unleashed all the visceral appeal of the organ’s leering tones. Gutsy guitars, practically tumescent electric piano, and coiling electric bass blossomed from a rich, velveteen soundstage. The Suns planted me deep in the sweet spot.

Solti conducting the London Symphony Orchestra in Bart¢k’s Music for Strings, Percussion, and Celesta (LP, London CS 6399) demonstrated the Suns’ rhythmic drive and textural acuity. Blazing left-to-right-channel orchestral salvos flew from the Suns, the speakers’ perfectly tuned coaxial drivers never trading speed for resolution and timbre. Those tiny drivers stopped on a dime. Even when letting go of notes as effortlessly as I’ve heard any speaker do, they gave up nothing to confusion, the massed strings singing as one, yet each instrument was individually distinguishable.

Trenner & Friedl Sun loudspeaker

Old and New Dreams is a crappy, narrowband recording of some great performances (LP, Black Saint BSR 0013). But listening to Eddie Blackwell drop agitated bass-drum bombs under Don Cherry’s pocket trumpet, Dewey Redman’s tenor sax, and especially Charlie Haden’s wiry double bass, is pure joy—a study in New Orleans standup drumming from a master sit-down drummer. The Suns didn’t hype the LP’s bland sound, but they did empower Blackwell’s bass drum to crank, boom, and splat for all its worth.

And talk about electric bass stealing the show! Playing Eddie Bo’s “If It’s Good to You” through the T&F-Heed combo was like hiding out in Dave Bartholomew and Cosimo Matassa’s J&M Recording Studio, on North Rampart Street. The Suns revealed Bo’s track as sounding viscerally wet and greasy—I could mop my face in it. The Suns delivered this gutsy soul music with impressive speed and slam. They revealed the overdriven electric bass’s cabinet resonance, the noisy fuzz guitar, the air-pushing sensations of the choogling drum beat. Bo and friends were holding a maniacal late-night party just the other side of the Suns, their New Orleans combustion blasting from the speakers’ tiny drivers with hot groove and dynamic energy to spare.

Trenner & Friedl’s little Suns bowled me over and blew me away. Rarely have I heard a loudspeaker with so many essential gifts in so small a package. Paired with an appropriately powerful amplifier, they had astounding rhythmic drive, exceptional tonal purity and transparency, textural faithfulness, the ability to “disappear” while creating finely detailed aural images, seamless coherence, grain-free reproduction of high frequencies, a generous midrange, and bass notes that outperformed those of every other minimonitor I’ve heard in extension and precision of definition.

The Sun is the finest stand-mounted speaker I’ve heard: a modern classic. The sum of $3450 is a not-insignificant one to spend on the reproduction of music in your home, but a pair of Suns is well worth it. If your dream is of sublime sound in a small space, the Sun just might fulfill it.