Gayle Martin Sanders co-founded (with Ronald Logan Sutherland) MartinLogan, one of high-end audio’s most iconic companies. Sanders’ greatest contribution was the breakthrough MartinLogan CLS (Curvilinear Line Source), a speaker that exemplified high-end audio’s purist approach. The CLS was a full-range electrostatic panel with no box, no crossover, and a single sheet of Mylar as its transducer. It was speaker technology boiled down to its simplest and most basic (although making a curved electrostatic panel work was anything but). The CLS, and its modern-day descendent, the CLX, set a standard for midrange resolution that has yet to be equaled by any loudspeaker, regardless of price or technology.
Sanders sold MartinLogan in 2005 and headed off into retirement. Or so he thought. With plenty of time on his hands, he couldn’t stop thinking about how advanced new digital-signal-processing technology could be brought to bear on problems in loudspeaker design that he had battled in the analog domain decades earlier. In 2015 he began to conceptualize a new type of loudspeaker, and in late 2019 launched a company, Eikon Audio, to bring to market the realization of his vision, the Image1 reviewed here.
The Image1 is the polar opposite of the CLS. That iconic electrostat was an exercise in minimalism; the new speaker pushes the envelope in complexity. Specifically, the Image1 is a complete integrated audio system featuring four-way active loudspeakers with dynamic drivers, four integral power amplifiers per speaker, digital-domain crossovers, DSP room correction, and remote control via phone or tablet.
Why this radical change in direction? Sanders believes that an integrated system such as the Image1 can address the many technical and commercial challenges that stand in the way of the wider adoption of high-performance music systems. Integrated systems can better fit physically and acoustically in homes; they are easier to use; they are less intimidating to non-audiophiles than component audio systems; they cost less by virtue of integrating many functions; and, perhaps most importantly, they offer the potential of improved performance. This last advantage is partly because all the system parts are engineered to work together and partly because digital signal processing can correct many of the fundamental problems of loudspeakers in rooms. You can read more about Sanders’ thinking on this subject in the accompanying interview.
The Image1 is a self-contained audio system that requires only a source to drive it, such as a computer, music server, or analog component. The Image1 consists of a pair of speakers and the Eikontrol box that contains the digital signal processing and DACs. The entire system costs $25,000, but that includes speakers, DACs, amplification, and cables. The Eikontrol electronics box accepts digital or analog signals from sources, implements a four-way crossover in the digital domain, performs room correction and other DSP, and then converts the four frequency-divided signals to analog with four DACs per channel. The Eikontrol’s output is four analog signals on balanced XLR jacks and unbalanced RCA jacks. These four outputs correspond directly to the four drivers in each speaker. Each output is a band-limited line-level analog signal that, when connected to the speaker via the supplied wiring harness, drives a power amplifier built into the enclosure, which in turn powers one of the speaker’s four drivers. The customer specifies the length of the wiring harness, which carries four XLR-terminated interconnects.
This architecture is different from most integrated systems in that the speaker is entirely analog, with the crossovers and DSP implemented in a separate box. Also unlike many integrated systems, the Image1 doesn’t provide integral support for streaming services. You’ll need a separate streamer or music server to supply a digital signal to the Eikontrol. (I used an Aurender W20’s USB output.)
The speaker itself is a four-way design with a front-firing 8″ woofer, a rear-firing 8″ woofer, a 5″ midrange, and a 1″ air-motion transformer (AMT) tweeter. Each of these drivers is powered by its own 100W Class D ICEpower amplifier. The ICEpower modules, chosen after Sanders auditioned a wide range of amplifiers, are modified for the specific drivers they will power. Because of the DSP crossovers earlier in the chain, the amplifiers are directly connected to the drivers, with no crossover components (inductors, capacitors, resistors) in the signal path. The digital crossover features compound slopes; they are relatively shallow near the crossover point so that the drivers’ outputs sum in-phase, but very steep a couple of octaves away.
The 5″ midrange driver reproduces the unusually wide frequency range of 125Hz–4kHz. In fact, you can think of the Image1 as a one-way speaker augmented at the top by the AMT tweeter and at the bottom by the two 8″ woofers. The idea was to reproduce as much of the spectrum as possible with a single driver, moving the crossover points away from the critical midband. The midrange driver can reportedly extend down to 60Hz (an octave below its operational range in the Image1), and is capable of very high excursion. It is ported out the rear to reduce back-pressure on the cone.
The two high-excursion 8″ woofers are loaded in an unusual quasi-transmission-line arrangement. In a full transmission line, the woofer’s rear wave is directed down a labyrinth filled with mineral wool (or other damping material) inside the cabinet. The woofer’s rear wave is dissipated as it travels down the labyrinth, and in theory is completely dissipated at the end of the transmission line (the opening in the speaker enclosure that looks like a port). A transmission line avoids the problem of sealed loading in which the trapped air inside the enclosure acts as a spring against the woofer as the woofer moves in. It also avoids the problem of reflex (ported) loading in which transient behavior is compromised and port artifacts (resonances, the sound of air moving through the port, etc.) can become audible. Although a transmission line has none of these problems, a true transmission line requires an enormous cabinet enclosing a very long labyrinth to fully dissipate the woofer’s rear wave. In a quasi-transmission line such as in the Image1, some woofer energy emerges from the end of the line, but it is greatly attenuated. The Image1’s transmission line gets progressively narrower, forcing the energy into a smaller and smaller area that has progressively greater damping. Sanders says that this unusual approach delivers tighter bass than traditional sealed or reflex loading.
Digital signal processing makes it possible to perform a simple but clever trick that allows the front- and rear-firing woofers to work perfectly together. Specifically, the signal driving the front woofer, the midrange, and tweeter is delayed just long enough for the rear-firing woofer’s wave to bend around the cabinet and reach the front baffle where it combines in-phase with the front woofer’s wave. This technique creates a null at the sides and rear of the cabinet, directing all the bass energy forward into the room rather than omnidirectionally where the bass would more strongly excite room modes. This is a great example of how DSP can solve acoustic problems that are intractable in the analog domain.
The cabinet is built from fine-grained MDF in a multi-constrained-layer-damped structure. Sheets of ceramic material are attached to the MDF with a flexible acoustic adhesive that has a specific compliance, and that stays flexible after it has cured. The ceramic layer forces cabinet resonances into the acoustic adhesive where it is dissipated as heat. The idea was to make the cabinet as quiet as possible yet keep the enclosure cost-effective. The multi-faceted enclosure, with its swept-back baffle, is designed to reduce diffraction. The baffle is matte black, and the sides, top panel, and rear are finished in a beautiful wood veneer. (The same veneer vendor supplies Rolls-Royce.) Three wood finishes are available.
The Eikontrol is a standard-size electronic component with a large front-panel display that indicates the system volume. A row of front-panel buttons selects an input, switches between stereo and mono, inverts polarity, mutes the output, and puts the unit in standby. The rear panel houses three digital inputs (USB, SPDIF, and TosLink) along with two pairs of balanced and two pairs of unbalanced analog inputs. Note that the analog inputs are immediately converted to PCM digital by on-board 96kHz/24-bit A/D converters. Eikon says that the Image1 may be upgradable in the future, and that additional features could be added. A bank of rear-panel DIP switches provides a rudimentary gain adjustment for the signal feeding the A/D converter, permitting -3dB, -6dB, or -12dB of attenuation (or no attenuation). Note also that the DACs operate at a maximum sampling frequency of 96kHz. Higher resolution signals must be downsampled in your music server to 96kHz. The digital-section designer, Bernt Böhmer, believes that D/A conversion is better performed at 96kHz than at higher frequencies because jitter becomes more audible the higher the sampling frequency. The DAC features custom digital filters with virtually no pre-ringing. An Ethernet and a USB communication port round out the rear-panel connections. The power supply is housed in a small outboard box.
System control is via a web-enabled device such as a smartphone or tablet. You simply connect the Eikontrol to your network (wired or wireless), enter its IP address in your browser, and a screen pops up on your phone or tablet with two volume controls (coarse and fine), a balance adjustment, and a mute on/off button. A row of buttons selects other screens. The Settings screen allows you to set up the system’s many functions, including the start-up volume, engaging the “home theater” mode, turning room correction on and off, and adjusting the frequency response with the “Contour” control. The Contour section is essentially a five-band equalizer that allows you to fine-tune the system to your room, or even for certain recordings. The Contour Memory will store up to eight equalization settings that you can engage with just a couple of taps. For example, I dialed down the “Brilliance” and “Low Treble” settings by a couple of dB each, saving the setting for recall on overly bright recordings. You are asked to name the settings as you create them so that they are recognizable later. A sixth adjustment on this menu, marked “Punch,” allows you to tune the low bass, from a tight and lean sound to a bigger, bloomier rendering. I found the Contour adjustments useful both in giving the system that last bit of tuning to my room, and also for shaving off excessive brightness in some recordings. One pitfall is that when swiping on this screen to access different frequencies you must be careful not to touch the other sliders because the system interprets this as an attempt to change the setting on the band that you accidentally touched. Also, any change in equalization or selection of a Contour memory causes the system to mute or sometimes stutter on and off for a few seconds, which is distracting. Overall, I would prefer to use a conventional remote control for volume and balance.
The Image1 incorporates DSP room correction, but it’s very different from conventional room correction. With conventional room correction, you place a measurement microphone at the listening position, drive the speakers with a test signal, and repeat the process with the microphone at various locations a few inches away from the prime listening position. The room correction program analyzes the frequency response peaks and dips, and then creates an equalizer in DSP from the measurement data that boosts the frequency bands where there are room-induced dips and attenuates those frequency bands that have room-induced peaks. The equalization curve is optimized specifically for that microphone/listening position, and may introduce large frequency-response errors outside the prime listening spot.
The Image1’s Wavelet room correction works very differently. Rather than trying to flatten the frequency response, the Image1 correction optimizes the system’s time behavior. It was designed by Swedish academic Bernt Böhmer using “wavelet” analysis of sound in a room, and is based on psychoacoustic principles of how we perceive time-domain information. It’s rather complex, so I’ve summarized in the sidebar how this system works, and how it is different from conventional room correction. In practice, the system is easy to calibrate. You (or your dealer) place the supplied measurement microphone 4′ from the speaker at tweeter level, push a few buttons on the app, and the system does the rest.
Gayle Sanders, Eikon’s Sales Manager Jerry Stoeckigt, and development engineer Evan Fahr visited me to set up the system and give me a technical briefing. During the visit we had a phone call with Bernt Böhmer in Sweden about the room correction and the A/D and D/A sections of the Image1, which he also designed.
Having seen the Image1 only in photographs, I was surprised by how small the speaker is—just 42″ high and with a very narrow baffle. It’s impossible not to look at a speaker’s size and drivers, and then consciously or unconsciously make assumptions about its bass extension, dynamic capabilities, and ability to present a sense of scale.
Whatever your expectations for the Image1 are in this regard, they are undoubtedly wrong, as mine were. If someone listened at length to the Image1 behind a curtain that prevented them from seeing the speaker, they would be shocked when the curtain was removed. The Image1 sounds like a big speaker in every way—soundstaging, bass extension and weight, and dynamic scale. The Image1’s ability to extend into the lowest bass regions, and to do so with such authority and effortlessness, is what I’d expect from a speaker at least twice its size. I don’t think that I’ve ever been more astounded by the quantity and quality of bass from a moderately sized speaker. The Image1 reproduced the full weight of a Fender bass, along with the impact and punch of a kick drum, with satisfying power and precision. Even when playing bass-heavy music at very high levels, the bottom end maintained its clarity and definition, never sounding thick or woolly, or exhibiting signs of stress. A good example is the hard-hitting Jeff Beck album Performing This Week . . . Live at Ronnie Scott’s with Vinnie Colaiuta’s depth-charge kick-drum barrage; the Image1 conveyed the power and energy of this remarkable trio at live listening levels with no hint of strain, dynamic compression, or congestion.
The Image1 is also very punchy, dynamic, fast, and full-bodied, and is remarkably adept at communicating an upbeat propulsive drive. I also got the impression that the Image1 had more dynamic headroom than I was using. A volume setting of 92 (out of 100) on the control display was a little louder than I’d ever want to listen, and I assume that the system is calibrated so that a volume setting of 100 is just below the point of driver overload (the power of DSP again). Incidentally, Eikon Audio specifies the Image1’s bass extension at 24Hz, a figure that I can believe. Unlike many frequency-response specs that state a low-frequency extension figure without a tolerance, Eikon Audio specifies the Image1’s response as being down by 2dB at 24Hz—a remarkable spec for any loudspeaker, never mind one of moderate size.
The bass was exceptional in other ways. It was extremely linear and smooth, with very little trace of the midbass thickness that plagues most speakers. The transient performance was outstanding, likely due in part to the use of two smaller woofers that can start and stop faster than larger cones. There was no trace of overhang or slowness in the bottom end, a quality that wonderfully conveyed an upbeat sense of music-making and propulsive drive. The bottom end was beautifully articulated in pitch and dynamics, making it easy to follow bass lines. It took a bit of placement experimentation to realize this performance (57″ from the rear wall), but it was worth the effort. Incidentally, my listening room has a volume of 5350 cubic feet.
And this was without room correction. Hearing the system with and without room correction was very different from my previous experience with DSP. First, unlike the radical reduction in midbass energy of most room-correction systems, there was only a very small change in the bass balance—it became just a little leaner. That could be because of my purpose-built room, the design of the Image1 itself (remember that the Eikontrol uses DSP tricks on the two woofers to reduce room-resonance excitation), or the fact that optimal speaker placement already realized fairly flat response at the listening position. But what the room correction did was at once subtle and profound. Don’t expect a huge reduction in midbass bloat, a general tightening of the bottom end (like pulling a trampoline taut), and a lighter-weight rendering. Rather, the correction system clarified and pulled into sharper focus the bass region. Bass lines that were a little smeared and homogenized became crystal clear in dynamics and tone color. The starts and stops of each note were better articulated, and the texture and body of acoustic bass was more richly portrayed. The inner timbral details that convey the mechanism by which the instrument produces sound were better resolved, increasing the sense of realism. While I had the Image1, I discovered the wonderful new live acoustic trio recording Trilogy 2 by Chick Corea, Christian McBride, and Brian Blade. Everyone plays beautifully on this album, and bassist McBride has never sounded more inspired. I intentionally listened to this album on the Image1 without room correction (I discovered this recording on my desktop system) to get familiar with it, and then later turned on the correction. Even without room correction, the Image1 did a great job of creating a tangible sense of a large instrument’s wooden body, the attacks of each note, and the nuances of McBride’s virtuosity. But turning on the correction took the alacrity and definition to the next level of realism. Think of looking through a lens that’s slightly out of focus, and then suddenly pulling perfect focus. That’s the effect of the Böhmer Wavelet correction in the Image1.
The room correction also affected the clarity, openness, and transparency of the midrange. With the correction engaged, the lower midrange was less “thick” (it wasn’t thick in an absolute sense without correction, only by comparison). The room correction “lightened” the midband and created a greater sense of the music existing in space independent of the loudspeakers. Vocals were clearer, with the midrange taking on an almost planar-like level of transparency. Unlike my other experiences with room correction, which were a mixed bag, I heard no downside or unnatural artifacts with the Image1’s correction. Significantly, the room correction didn’t degrade the tonal balance or timbre through the midrange and treble.
As great as the Image1’s bass performance was, the midrange was just as impressive. Voices were particularly well served by the Image1’s smoothness, clarity, openness, and resolution. The midrange driver’s wideband operation conferred a sense of seamlessness and coherence, qualities that went a long way toward the natural rendering of timbre. The midrange couldn’t be characterized as “forward” or “laid-back”; rather, it had very little character and color of its own.
The treble was open, extended, airy, and well-integrated with the mids. The top-end’s texture was a bit on the dry side, with a hint of excessive brightness on cymbals and vocal sibilance. The dryness seemed to span just a portion of the treble range, primarily centered on “sss” sounds in closely miked vocals. The Contour control’s “Brilliance” and “Low Treble” adjustments were extremely useful in realizing a smoother and more relaxed sound. I shaved off a couple of dB in the treble for most of my listening.
In the ability to portray the large scale of orchestral recordings, the Image1 was surprisingly good, particularly considering its moderate size. The speaker’s relatively short stature (42″) didn’t result in a soundstage confined to head-level; instead, the stage was wide open in width, height, and depth. Image specificity was particularly good, with clearly defined placement and image outlines. Many speaker systems become less precise in the imaging of low-frequency instruments, but the Image1 maintained its sharp image focus across the entire spectrum.
The digital nature of integrated systems requires that analog sources be digitized and then converted back to analog. Obviously, introducing an A/D and D/A conversion in an analog signal path will inevitably result in some audible degradation, particularly if you have very good quality analog sources. Nonetheless, the Eikontrol’s A/D and D/A were quite good judging by the sound quality of the system when playing LPs. Despite the added conversions, vinyl sounded clean, open, and spacious, without the attendant reduction in space and hardening of timbre of lesser-quality conversions. If the Image1 appeals to you and you play vinyl, I think that you’ll be pleasantly surprised by the A/D quality.
A fundamental question posed by a product like the Image1 is whether its performance can be matched, or exceeded, by a component-audio system of the same price. I imagined the system I’d put together with a $25,000 budget for an integrated amplifier, DAC (or DAC module in the integrated amp), speakers, and cables. It’s highly unlikely that the component audio system could match the Image1 in any aspect of the bass performance—extension, resolution, power and weight, pitch precision, dynamic impact, or clarity. The room-correction system elevates what was already exceptional bass performance to a new level. The Image1’s midrange and treble quality and balance could be equaled by a component system provided those components were carefully chosen. The Image1, however, can be tuned to the room via the Contour controls, which is not possible with most component-audio systems.
Toward the end of my time with the Image1, I put on an old standard that I’ve used in just about every speaker evaluation over the past 20 years, Keith Johnson’s remarkable recording of Rutter’s Requiem on Reference Recordings. I listened to this title on the Image1 primarily to hear how low the bass extends, and to gauge how well the speaker conveyed the pitch of the organ pedal points in the wonderful acoustic of Myerson Symphony Center. Yes, the Image1’s bass extension and pitch precision were exceptional, but I quickly found myself immersed in the way the Image1 presented a natural rendering of instruments and massed voices within a huge and beautifully portrayed acoustic space. This recording demonstrated everything that the Image1 does well—presenting a huge sense of scale, precise imaging, realistic timbre (particularly on the massed voices), superb bass extension and clarity, and just a generally well-rounded and engaging musicality.
The Eikon Audio Image1 is a bold, forward-thinking product that brings something new and different to high-end audio. By combining the friendliness of a “lifestyle” system with the sonic performance of high-end audio, the Image1 makes great sound easily accessible to anyone who loves music. The Image1 is also an ideal system for someone downsizing and looking to eliminate “system clutter.”
Among its many virtues, the Image1 can deliver big-speaker sound in a package small enough to fit in just about any room. The bass performance is outstanding, aided by the innovative DSP room-correction system. In the ability to present a large sense of scale, spatial and dynamic, the Image1 is an overachiever.
Still, the Image1 isn’t for everyone. It isn’t compatible with DSD or MQA, can’t be upgraded over time, and requires that analog signals be digitized. For many listeners, however, the Image1’s simplicity of operation and sound quality will outweigh these limitations. If you want a great-sounding system that liberates you from thinking about your next upgrade, the Eikon Audio Image1 is hard to beat.
Specs & Pricing
Frequency response: 24Hz–24kHz ±2dB
Driver complement: One forward-firing 8″ woofer, one rear-firing 8″ woofer, 5″ midrange, AMT tweeter
Loading: Quasi-transmission-line bass, vented midrange
Inputs: Four line-level on balanced XLR jacks, AC power
Integral amplification: Four 100W Class D
Dimensions: 9.5″ x 42″ x 15″
Weight: 95 lbs. each
Analog inputs: Two pairs stereo balanced XLR, two pairs unbalanced RCA, XLR measurement microphone; input attenuation of –3dB, –6dB, –12dB
Digital inputs: USB, SPDIF, TosLink
A/D conversion: 96kHz/24-bit PCM
D/A conversion: 96kHz/24-bit PCM
Analog outputs: Four balanced on XLR and RCA connectors per channel
DSP: Analog Devices 96kHz/56-bit
Processing: Wavelet time and amplitude correction
Crossover: Four-way, digital domain
Control interface: Ethernet, TP-cable, WLAN
Supplied accessories: Measurement microphone, microphone tripod
Dimensions: 17.52″ x 3.74″ x 11.85″
Weight: 13.5 lbs.
System price: $25,000
Shunyata Sigma AC power cords
Berkeley Alpha USB USB-to-AES converter
By Robert Harley
My older brother Stephen introduced me to music when I was about 12 years old. Stephen was a prodigious musical talent (he went on to get a degree in Composition) who generously shared his records and passion for music with his little brother.More articles from this editor