I first laid eyes on the $175,000 Gauder Akustik Berlina RC 9 loudspeakers at CES 2015. They were part of a system put together by Axiss Audio that included Air Tight reference tube electronics and the company’s Opus-1 cartridge mounted on a Transrotor Tourbillion ’table. That room earned my cost-no-object Best of Show award. The sound was full and rich with plenty of body and macro-dynamic oomph on an orchestral recording I brought along for audition. There was no hint of the edge, brightness, or sterility that has been known to plague certain ceramic-driver designs in the past. Instead, there was an exceptional portrayal of what was on the recording without any colorations that I could identify being superimposed by the speakers.
The Berlina RC 9 is a reference-quality four-way speaker system utilizing a ¾” pure-diamond tweeter, a 2″ pure-diamond midrange driver, a 7″ ceramic lower-midrange driver, and three 7″ ceramic woofers paralleled in a 12th-order bass-reflex enclosure.
This completely custom creation is derived from the mathematical models developed for the speaker by Gauder Akustik. Without getting too technical, Dr. Roland Gauder, a physicist, uses Euler’s formulas to describe every parameter of the speaker system (drivers, cabinet, and crossover) and its performance characteristics (including vibration, oscillation, damping and decay of driver diaphragms, cabinet materials, and electrical components). Laplace transforms are then applied to create transfer functions from which the cabinet size, Thiele-Small parameters, and values of electrical components can be calculated.
Dr. Gauder’s physics-driven, top-down systems-design approach means there are no off-the-shelf driver solutions. Everything must be custom-made. For the drivers, the derived Thiele-Small parameters (along with additional requirements) are transferred to the manufacturer, who then produces the exact physical component specified via the mathematics. There is no room for compromise or deviation with such designs; the drivers have to be made precisely as ordered-up by Dr. Gauder. The German dynamic-driver company Thiel & Partner GmbH met this challenge, and was able to construct custom Accuton (diamond and ceramic) drivers for the RC 9. Strict adherence to specifications has resulted in drivers that are rigid and nimble and that have strong magnetic properties. These custom drivers perform, as required, without the modifications, patches, and accommodations typically necessary to fit or tune a driver into a loudspeaker.
The crossover network is also part of this systems-design approach. The RC 9 crossover moves into the rare area (for loudspeakers) of having greater than 60dB-per-octave passive networks, with less than half-an-octave of acoustic overlap between the drivers. Additionally, the four-way crossover network is symmetrical, which significantly increases its complexity, but Dr. Gauder feels the sonic results are more than worth the expense and effort for his reference Berlina RC 9 loudspeaker. The benefit of symmetrical crossover design (which puts components into both the positive and negative legs of the speaker connection) is said to be to a more natural sound, and an easier load on the power amplifier. According to Gauder Akustik, the components in the crossover are exclusively sourced from Mundorf and Intertechnik, ensuring consistency, quality, and reliability.
The bass section of the Berlina is unique in two ways. First, the bass is high-pass-filtered to 21Hz, so there is no need to be concerned about DC leakage current from the amplifier’s speaker output terminals or subsonic rumble from analog sources directly affecting the RC 9’s performance. The other feature is an equalization system that allows the bass to be tailored to the room. On the rear of the speaker there is an electrical selector plug for “Dynamic Bass Control.” The choices are a 0dB neutral setting along with a +1.5dB boost and a -1.5dB cut. If the selector plug is completely removed, the user will gain an additional setting that provides a -3dB cut. The effect of this room equalization is mostly, but not exclusively, observed in the 70–100Hz range where room peaks, lack of energy, and other anomalies are typically noticeable and may need to be controlled.
The RC 9 enclosure features a high-quality oval-shaped rib construction—from which the “RC” in the name is derived. The idea came to Dr. Gauder when contemplating how he thought nature would build a loudspeaker—like a human, with a sternum (faceplate), ribs (sides), and spine (for stability)—to enclose a volume of low resonance. Dr. Gauder chose the construction technique in order to suppress any loudspeaker’s inherent tendency to vibrate and add unwanted resonant energy to the sound. To accomplish his goal of removing as much vibration as he could, the Berlina RC 9 uses a stack of 50mm individual ribs separated by 4mm damping ribs. Gauder Akustik believes that these thick, heavy, stiff ribs create favorable conditions to keep vibrations from interfering with the speaker’s sonic reproduction of source material. To further reduce and isolate vibrations, each of the adjacent 50mm single ribs is structurally different. The RC 9 cabinet is constructed with 26 single ribs and 25 damping ribs. The front faceplate is 38mm thick with an additional 3mm of constrained-layer-damped heavy black flagstone that has a textured finish to further help break up acoustic resonances. The ribs are compressed together with six threaded rods, three on each side) that provide the necessary pressure to acoustically seal the enclosure. On the rear of RC 9 are two sets of WBT NextGen binding posts that allow bi-amp or bi-wire configurations. The bottom of the rib construction has the port for the bass-reflex system at a fixed distance from the bottom granite base upon which the speaker sits. This base is made of black Star Galaxy granite—which is what is used in the trim of some Mercedes-Benz automobiles, among other high-end stone applications—connected to the lower rib by three stainless cone footers. The single ribs are finished in high-quality, high-gloss piano white or black.
In late February of 2015, I received an inquiry about reviewing the Berlina RC 9. In mid-April, Gauder Akustik’s U.S. distributor Arturo Manzano of Axiss Audio in California and Dr. Roland Gauder himself flew in to install the Berlina RC 9s in my listening room. The speakers arrived in individual wooden crates, side by side on a single pallet. To begin the installation, the top/side covers of the wooden crates are removed from the pallet; inside, each speaker is secured, face down, on a rolling base. Once the bottom of the crate is removed, the 220-pound speakers are easily rolled into the listening area. There, the speakers are lifted to their vertical position with the rolling bases still attached. Straps securing the speakers to the bases are then removed, which allows the two speakers to be separated. Once their protective cloth covers are lifted off, the attractively finished products are ready for speaker-wire connection, position adjustment, and playback.
The Berlina RC 9 speakers I received were the same ones I’d heard at CES 2015. The speakers had a high-gloss piano-white finish with white damping rings. This external color, juxtaposed against the black flagstone faceplate holding the pure-diamond and ceramic drivers, made a striking visual appearance.
My listening room is approximately 18′ wide and 43′ deep, with an 8′ ceiling (a little over 6000 cubic feet). The listening space has permanent openings that add few thousand cubic feet of additional space. This room has proven to be very good with low frequencies. Subjectively, the room doesn’t overload with bass, and measured low-frequency response is typically very smooth across the frequency spectrum. We set the Berlina RC 9 speakers in a position along the 18′ wall that has worked well for nearly all the speakers that I’ve used. During setup, we could adjust the speakers for improvements and use the supplied Gauder Akustik test-signal CD to adjust bass.
Once the speakers were set in place and connected, I did some initial listening. The imaging and balance I’d heard at CES were there from the start, and the sound was better than expected with the speakers just installed in a new environment. Initially satisfied, I handed the remote control to Dr. Roland Gauder and Arturo Manzano. Upon listening, all three of us felt the location initially selected sounded very good. Dr. Gauder ran through a series of CDs he brought along with him to hear the performance of the system and make adjustments if necessary. My observation was that with each successive test track from his selected CD, he became more at ease. After some time had passed and the Dynamic Bass Control was adjusted +1.5dB to accommodate my room’s acoustics and the speakers’ position (which is more than seven feet out from the wall behind them), we switched to vinyl playback. This is where things really took off and the sound quality increased. Despite the vinyl format’s technical flaws, subjective listening still shows why it is often the preferred playback medium for many listeners. Since the setup and first listen went so well, we ended up playing vinyl from my collection for much of that afternoon. Most of my observations for that day were made off to the side of the listening area, since the distributor and manufacturer as my guests were sitting in the center position. What I can say is that even in the side listening position, I could easily observe proper placement of images and a tonal balance that was above average by a significant margin.
Later that afternoon, we switched the electronics to an Accuphase C-2820 preamp, A-70 amp, and DP-720 SACD/CD player. With the Accuphase electronics in the system, the Berlinas took on a slightly darker character with a generously full lower-midrange and upper bass. Some of the same songs had a bit more grunt and a little less sparkle. With either configuration, the RC 9 speakers were capable of providing significant amounts of music enjoyment and of revealing whatever hint of character the accompanying electronics possessed. The next day we did much of the same listening with different component combinations. In each case, the sound was above average by any measure I could think of.
I was pleased that the distributor and manufacturer were both happy with the sound they heard. Knowing the speakers only had 60 hours of playing time prior to CES 2015 and that there would be time for everything to settle in, I knew the sound would only get better (and it sure did).
While the Berlina RC 9 speakers were in for review, they were also used, in part, for my Ortofon A95 and Ayon CD-3sx reviews. Even though I could clearly identify everything reported during the review periods with my own speakers, when the Berlina RC 9 was playing, every aspect of the sound was cast in greater relief. The performance differences identified between the MC A95 and MC Anna were even clearer. The smooth operation of the Ayon CD-3sx was more apparent. The strengths and weaknesses of cartridges, turntables, phonostages, digital players, CD players, and other source components were heard with greater clarity. The preamps available during the evaluation (Accuphase C-2820, Dual Placette Active linestages, and the Siltech SAGA C1) showed clear sonic differences.
The amplifiers used with the Berlina RC 9 speakers were the most interesting in terms of equipment differences. Because this was a speaker review, I wanted to at least try a handful of different topologies. On my list of amplifier types were Class AB solid-state (custom 1500Wpc mono amps and the Sanders Magtech stereo amp); Class A solid-state (Accuphase A-70 stereo amp); tube/solid-state hybrid (custom 300Wpc mono amps); ZOTL (Berning ZH-270 stereo amplifier); and transformer-coupled tube amplifier (two VAC Signature 200 iQ stereo amplifiers). Trying all these amps allowed me to better assess the speaker’s characteristics with music (discussed later) and observe the behavior of the speaker/amplifier pairing to help determine what each component was doing.
The two high-power Class AB amplifiers paired with the Berlina RC 9s possessed near unlimited dynamics (from micro to macro), incredible speed, frequency extension at both ends of the spectrum, and a wide soundstage. They did differ in soundstage depth with the Magtech amplifier being a bit shallower, while the custom amplifier was as deep as the tube amplifiers. The Magtech had the greatest control in the bass of any of the amplifiers—some might think it was too controlled, but the bass was certainly very tight. The custom amplifier’s bass wasn’t as tight with the Berlinas, by comparison, and a little fuller sounding as a result. Midrange and high-frequency differences in clarity were also recognizable with both amplifiers.
The Class A Accuphase A-70 proved to be as powerful sounding as the Class AB amplifiers within its power envelope. This 60Wpc (nominal) stereo amplifier has a minimum of 3dB headroom, meaning it will produce 120Wpc into an 8-ohm load when called for. Additionally, the amplifier doubles its output as the load is halved. The Berlina RC 9s have 4-ohm (nominal) impedance (with an uncalibrated measurement I took of around just below 3 ohms at the lowest point). One additional feature of the A-70 is the ability to accurately track real-time power output on its display. With this amplifier in the system, I witnessed a local reviewer, who gave a listen during the manufacturer’s visit, push the amplifier to well over 400+ watt peaks during some musical passages. Dr. Gauder mentioned the speakers can take that kind of peak power (up to 580 watts to be exact) without damaging the drivers. Needless to say, the amplifier packs a lot more power than expected. The sound produced with this amp in the system was bolder, bigger, and slightly fuller. There was less high-frequency emphasis and a warmer midrange. The upper midrange remained intact but the overall presentation was slightly burnished. Overall, the sound was favorable, powerful, and very enjoyable.
With the hybrid tube amplifier, the RC 9 had sonic characteristics similar to the A-70 without the added heft and grip in the low frequencies. In some ways it was a more polite version of the A-70 with a less burnished upper midrange and more even emphasis in the transition to higher frequencies. What I missed with this amplifier was the drive of the all-solid-state amplifiers mentioned above. What I gained was a subjectively smoother and purer sound with a soundstage as deep as any amplifier on hand. Overall very nice sounding, very well put together, with a bit less flamboyance when the music called for same.
Even though the Berning ZH-270 has power output similar to the Accuphase A-70, driving the Berlina RC 9 was a bit of a challenge for it. This particular amplifier sounds wonderful with the right speaker, but the RC 9 is not a good match. At low volume levels, the sound was fine but once moderate-to-loud levels are required, the amplifier begins to sound compressed and to lose dynamics. To the amplifier’s credit, I’ve heard it do exceptional things with easier speaker loads in less demanding situations. In the case of the RC 9, this is a clear example of what not to pair the speaker with. Neither component will show its otherwise exceptional capabilities.
Pairing the VAC Signature 200 iQ Stereo amplifiers with the Gauder Berlina RC 9 proved to be as enjoyable as the pairing with the solid-state amplifiers. Interestingly enough, with two VAC stereo amplifiers, I was able to try two amplifier configurations (monoblock and stereo bi-amp) plus two tube combinations (stock and optional Russian tubes), in addition to the different transformer taps available. A pair of these amplifiers offers exceptional versatility for the end user. First listen was with the optional Russian tubes (Tungsol and Gold Lion). Paired with the Berlina RC 9 in mono configuration, the sound was full, warm, smooth, and ever so slightly round in the low frequencies. When I switched to stereo mode and bi-amping, the RC 9 created a bit more clarity through the upper midrange and treble, which the speakers reproduced extremely well. In this configuration, the sound character remained the same as in the mono configuration but with a bit more air. In some cases, a highly resolving speaker will benefit from taking a bit off the top, so to speak. The Gauders, however, can take as much low-distortion resolution as the electronics can provide. When I switched to the stock tubes for the Signature 200 iQ amps, the top end opened up and resolution began to pour into the speakers with clarity and purpose. What I has been missing with the optional tubes was now there without any loss of fullness in the low registers. In fact, using the stock tubes with the stereo bi-amp configuration was my favorite tube pairing with the RC 9. I suspect that any user who must have a tube amplifier would do well to try this combination—just make sure to try the stock tubes before making a judgment.
Having listened to the Berlina RC 9 with so many amplifier combinations allows me to better comment on the speaker’s sonic capabilities in any system.
In the second movement of Bach’s Concerto in D major on the Jacques Loussier Trio LP of Bach to the Future, there are sections where only a cymbal is sounded. As reproduced by the RC 9, these solo cymbal strikes shimmered realistically with a sweet and lovely sound that seemingly went on forever. In this same movement, where the contrabass “walks” the scale, the fingering on the strings and powerful-sounding timbre created an illusion of the real thing. Combined with the delicate piano playing, this movement made me feel as if the entire performance were being reproduced in my mid-sized space. When the third movement kicked in, the tempo picked up and the drum kit became more powerful, fast, and tight sounding. One could still focus on the contrabass while the piano’s quick rhythm created beautiful sound. Through the RC 9 every aspect of this recording was enhanced and enjoyable.
Moving to Ella Fitzgerald and Joe Pass’ Speak Love LP, on “Speak Low,” Ella’s voice sounded very dynamic, natural, and clear; Joe Pass’ guitar, just to the right of center stage, provided the musical foundation with rock-steady rhythmic playing. On “Comes Love,” Ella’s dynamic fortissimos were even louder than on the first track, and the clarity of playback revealed several page-turns of the sheet music. This track, in most cases, serves as a focused test for dynamic breakup in a cartridge or speaker. With the RC 9, there was nothing but music and more resolution than previously heard.
“I Don’t Stand a Ghost of a Chance with You” from Linda Rondstadt’s What’s New LP shows a mix of jazz and orchestral playing in a single song. The well-recorded sax, drums, and piano were easily identifiable on the RC 9, while Linda’s voice transitioned effortlessly from delicate to dynamically soaring. While all of this was going on, orchestral placement was near perfect and realistic sounding. This was the clearest playback I’ve ever heard of this recording.
Playing “Kings of the Highway” from Chris Isaak’s Heart Shaped World LP through the Gauder Berlina RC 9 produced a saturated soundstage in which it was easy to follow all that was going on. Vocals were reinforced with overdubs, something that I’d not picked up on as easily before. The speakers maintained their composure no matter what volume was selected, which tended to lead to a desire to continually increase the level in order to feel more of the drive and pace in the music. Moving to “Blue Spanish Sky” provided a nice musical contrast that still played big, even though the tempo was much slower. Isaak’s voice sounds deeper than on the previous song, the soundstage was clearer sounding, the guitar played a lower scale, and the occasional trumpet took on an ethereal quality.
On Nadja Salerno-Sonnenberg’s performance of Prokofiev’s Sonata No.1, the speaker’s ability to capture the beauty, speed, and transient response of the violin and the realistic timbre and dynamic of Sandra Rivers’ piano in a real space was on fullest display. The superb timing of this performance was felt to a greater degree than I’d previously heard in my system.
Mobile Fidelity’s reissue of Dire Straits’ Brothers In Arms served as a fitting bookend to this musical tour. On its own, this LP is the best version of Brothers In Arms I’ve ever heard. “So Far Away” started off with a strong drumbeat that was big with plenty of power. The snare was clean, and so were the guitar and vocals. When the LP moved to the second track, “Money For Nothing,” I felt as if the floodgates opened and there was a wash of energy from this song I’ve never experienced before—gut-wrenching bass and a crisply pounding snare drum. (An added enjoyment was the occasional double-kick of the bass drum.) Along with this sensational low-frequency drive, the performance was cleaner than I’ve ever heard it sound before. When played back on the Gauder Berlina RC 9, the left channel guitar’s cut and boost were also clearer than I’d ever heard before. Additionally, this particular LP played extremely cleanly at levels that climbed over 100dB, during moments of weakness when I allowed the system to breathe a bit more than usual.
With the above-mentioned listening examples and equipment combinations, the Gauder Acoustic Berlina RC 9 showed itself to be a formidable speaker by any measure. So much so, it earned a 2015 Golden Ear Award from me. In many ways, I feel that loudspeaker choices are personal. Their character tends to set the limits of what’s possible with playback systems. The old adage that resolution lost can never be recovered fits all components in the listening chain, but none more than speakers, since they are the last bastion of potential purity from which the music must emerge.
Having said this, I’d like to conclude with a version of the text from my Golden Ear Award. Loudspeakers are often described as being a window to the performance. The best of them remove the window (and walls) entirely in an effort to place you within the performance, capture you, and let you explore—holistically or analytically—the essence of the composition as well as the individual music lines. The Berlina RC 9 fits the description of the best of them. This is not because of price (which is in part the result of using incredibly expensive pure-diamond midrange and tweeter drivers); it is because of the consistently stable pianissimo-to-fortississimo resolution, clarity, and dynamic capabilities within its methodically crafted DNA. This loudspeaker plays like a chameleon to music reproduction, as well as to the source and amplification components in front of it. Choose the correct amplifiier and be rewarded with reference-quality sound. An audition is highly recommended.
SPECS & PRICING
Type: Four-way dynamic loudspeaker
Drivers: 3/4″ diamond tweeter, 2″ diamond midrange, 7″ ceramic lower-midrange, three 7″ ceramic woofers
Bass principle: 12th-order symmetrical bass-reflex
Crossover type: Symmetrical four-way
Crossover frequencies: 150/1000/6000Hz
Crossover slope: ›50dB/octave
Sinewave power handling: 340W
Impulse power handling: 750W
Dimensions: 23/34 cm x 145 cm x 61 cm
Weight: 102 kg
DE – 71272 Renningen
AXISS AUDIO (U.S. Distributor)
17800 South Main Street,
Gardena, CA 90248
By Andre Jennings
My professional career has spanned 30+ years in electronics engineering. Some of the interesting products I’ve been involved with include Cellular Digital Packet Data modems, automotive ignition-interlock systems, military force protection/communications systems, and thrust-vector controls for space launch vehicles.More articles from this editor
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