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Gradient Revolution is a unique combination of advantages of a big panel loudspeaker and a mini monitor. Turnable and open dipole bass section with coaxial upper unit differs dramatically from ordinary loudspeaker designs.

With these unique principles Revolution was designed to be extremely room independent.

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If we could have a magician conjure up the ideal loudspeaker from all the properties of current designs, the result could be as follows: A large dipole panel speaker which generates standing waves only in one direction. Because of the narrow dispersion it generates less unwanted room reflections. The resulting sound is clean, airy and non-boxy. Or a small two-way mini-monitor will give a very accurate soundstage and a wide listening area.

If we combine these good properties, and ignore the bad ones (narrow listening window of a panel speaker and the fact it cannot be positioned against the back wall, the weak bass response in mini-monitors, etc.) the result would be an ideal loudspeaker.


The bass part of Gradient Revolution loudspeaker consists of two 300mm custom made long throw woofers. They are assembled on an open baffle giving the low frequencies a "figure eight" or dipole radiation pattern similar to most panel loudspeakers. These two woofers operate from below 30Hz up to 200Hz.

An ordinary box speaker radiates in all directions at low frequencies. This has the unfortunate effect of generating standing waves in all dimensions (HxWxD). In the typical listening room, standing waves distort the sound at frequencies below 200Hz. Gradient Revolution does not excite standing waves between the floor and the ceiling, it can only generate them in the direction of the radiation pattern.

The woofer section of the Revolution can be rotated and directed in three different ways, to minimize undesirable standing waves in the listening area. This ability to "tune" out standing waves in the bass is unique. The result is a smooth articulate bass response which has correct musical pitch and dynamics.


Frequencies over 200Hz are reproduced by a coincident driver assembly. A 170mm fiberglass cone handles frequencies up to 2800Hz. High frequencies from 2800Hz to over 20kHz are reproduced by a 25mm aluminum dome tweeter placed at the apex of the midrange cone. A point source is generally accepted as an ideal sound source for its excellent phase and amplitude response. This results in an extremely accurate, stable and three dimensional soundstage.


The midrange driver is mounted in an acoustic resistance enclosure giving the system a cardioid (heart shape) radiation pattern. The dome tweeter uses the cone of the midrange driver as a wave guide thereby providing the same cardioid pattern.

From 200Hz up, the speaker radiates sound mainly in the forward direction. The rear radiation is effectively damped by having a power ratio of 100 to 1. This minimizes any early reflections when the speaker is placed against the back wall. Special attention has also been taken that the radiation patterns are consistent at all frequencies. The design of the speaker also minimizes sound reflections from the cabinet itself and nearby boundaries, thus negating the effects of diffraction. The room influence to the sound remains very small, especially at mid and high frequencies giving the Revolution a very similar sound characteristic in many different rooms.


The frequency response of the Revolution at the listening position is extremely flat; but this alone is not sufficient for Gradient. Every speaker radiates at least some sound in all directions. If the energy response of a loudspeaker has peaks and dips, the reverberant sound field will be uneven, coloring the music. Frequency response measured in all directions must be linear - as with the Revolution - in order to ensure linear energy response.


Many of the superior sonic qualities of this speaker has been achieved by a properly designed crossover filter. The electrical response of the filter alone has very little meaning - except in terms of power handling. More important are the acoustical responses of the drive unit/filter combinations and how they are tailored to work together in a multiway speaker system. The acoustical slopes are 18 and 24dB/octave. The two-part crossover consists of selected components: air core inductors, wire wound resistors, and polyester film capacitors.


Gradient Revolution can be positioned in the room like a dipole speaker. In this case one or two meters from the rear wall is beneficial. Unlike panel speakers, the bass section of the Revolution can be directed in three different ways allowing for unique control over unwanted standing waves. If a panel speaker is positioned near the rear wall the bass output will be attenuated strongly and the midrange will be colored by early reflections.

Gradient Revolution overcomes both of these problems. When positioned against the wall the bass section will be faced toward the adjacent wall. The bass can be attenuated by increasing the distance from the rear wall and fine tuned by rotating the speaker a few degrees. Due to the radiation pattern at middle and high frequencies, unwanted early reflections are not created. The music will remain smooth and open with correct timbre as with conventional panel speaker positioning.


The Gradient Revolution loudspeakers are designed for the most demanding audio enthusiasts. However there are good reasons to use them as main loudspeakers in a home cinema system.


Gradient Revolution is designed and hand built in Finland with professional craftsmanship and very high quality materials. In addition to the variety of standard finishes, Gradient Revolution may be customized with a huge variety of options. In total over 20 different high quality fabrics and multiple real wood veneers allow personalized speakers for every taste. 

Data sheet
Make and modelGradient Revolution MK IV
Radiation patternsBass: dipole, midrange & treble: cardioid
Frequency response50-20000Hz +/-2dB, -6dB@30Hz, high frequency limit above 50kHz
Impedance6 Ohm, minimum 5 Ohm
Recommended amplifier power50-250W
Drivers2×300mm long throw woofer, 176mm fibreglass midrange, coaxial aluminum dome 25mm
Crossover frequency200Hz and 2800Hz
FeaturesBass level adjustment
ConnectionsTwo pairs of binding posts
Dimensions (WHD)41 × 102 × 36cm
Room sizeMedium - Large
Suitable for home cinemaYes
Made inFinland
Reviews and awards


‘ Quite the best, the truest reproduction of an orchestra I experienced at the show, with some of the most accurate bass reproduction I’ve heard anywhere. ‘ -Paul Seydor, T.H.E. Show Newport Report, The Absolute Sound, June 2012.

‘ Several amazing pieces of organ music, live club jazz and female vocals proved to be intoxicating. The sonic imaging placed me in the room where each of the recordings was made, and each projected a different-sized space. Holographic would be the best word to describe this system. Whether sitting in front or standing in back of the speakers, the sound was so extremely visceral and huge that you could easily lose yourself in the illusion of being at a live music event. This was the most realistic and musical sound at the 2012 New York Audio Show. ‘ -Jeremy R. Kipnis, (April 2012)

Read the full report here:

‘ The sound in the Gradient room, with everything running, was quite simply unrivaled at this show. ‘ -Scot Hull, New York Audio & AV Show 2012, Part-Time Audiophile (April 2012)

Read the full report here:

‘ Gradient Conquers Room Acoustics - The sound was open, clear, and vibrant, with well-defined images placed across a wide stage. I heard no evidence of the bass problems that troubled many other systems. ‘ -John Atkinson & Stephen Mejias, New York Audio & AV Show 2012 coverage, Stereophile (April 2012)

Coup de Coeur - Award in the SSI 2012:

‘ Pour moins de 10 000$ tout compris, il n’y a rien sur le marché qui puisse arriver à détrôner le résultat sonore des Gradient Revolution, voilà la raison principale du pourquoi Tim .G Ryan remporte un « best sound of the show » à chaque salon. ‘ -Marc Philip, Magazine Audio (April 2012)

‘ Best Sound of the Show (TAVES 2011) ‘ 

-Marc Philip, Magazine Audio (October 2011)

Best in Show at CAS 2011:

‘ Aesthetically, this resulted in my favorite sound that I heard all weekend.’... ‘ The bass in this room was perfect... impactful, but not boomy, and fast. There is a section in "The Real Blues" where Ray Brown plays a fast run down to the low E, slapping the strings all the way. This tight combination of high frequency and low frequency information is a mess unless the bass is lightning quick, and I didn't hear it played better on any system at the show.

You hear the exclamation, "the speakers disappeared" all the time, but when it really happens, it is breathtaking... and my breath was taken by the Revolutions. They projected a sonic hologram... when I closed my eyes I felt I was no longer in a hotel room at all. When it needed to, it placed a solo performer right there in the room with us. For larger-scale recordings, sound seemed to come from well beyond the physical walls. ‘ -Clarke Robinson, CAS 2011 Show Report, Enjoy the (August 2011)

Read the full report here :

' This was one of my favorite listening experiences of the California Audio Show... While many exhibitors struggled with the sound of their rooms, employing careful, creative speaker placement and a variety of room acoustics treatments, SimpliFi Audio’s Tim Ryan seemed happy to ignore the room altogether..... I was surprised to see that Ryan had used NO room treatments whatsoever.'

- Stephen Mejias, CAS 2011 Show Report, Srereophile (July 2011)

Read the full report here :

‘ I carried around an excelent recording I know well (Eargle's recording of Dvorak's New World), which I have listened to on quite a few carefully corrected systems. I have a good idea of what this ought to sound like...Gradient Revolution with extra bass towers: Small room but excellent truth to tonal character, solid precise bass, correct sense of space, good all around. Sounded a lot like an orchestra, to the extent that that can be done in a small room...Gradient'Simplifi, whose exhibit was one of the very best, making most of the rest sound foolish, was using a $500 amplifier. Of course, no one noticed from listening. No one ever does. ‘

-Robert E. Greene, THE Show Report, REG’s Audio Forum (June 2011)

‘ Gradient craftily left their room door open, and I found myself incapable of walking past it without being drawn in by the wonderful sound. These speakers are clearly worth further evaluation. ‘ - Alan Taffel on THE Show Newport Beach, (June 2011)

‘ Gradient Revolutions, with the active Gradient subwoofers, presented the most accurate replication of a full orchestra with respect to timbral accuracy and tonal weight, and it was certainly no sluggard in the dynamics department...had among the truest, most accurate bass at the show. ‘ - Paul Seydor on THE Show Newport Beach, (June 2011)

‘ Best Sound of the SSI Show (Montreal SSI 2011) ‘ -Marc Philip, Magazine Audio (April 2011)

‘ I suppose it’s clear that I really like these speakers, but my admiration goes far beyond simply liking how they sound. To me this design represents a fundamental improvement over most others by directly and successfully treating the problems of room and speaker interaction. In my experience, the resulting immersion in the originally recorded soundfield is otherwise only available in “near-field” listening. Anyone with serious audio interests ought to listen carefully to the Gradient Revolution for the pleasure of it, and also to hear what is possible when a speaker can “ignore” the room around it. You can spend far more money, but you are unlikely to find a speaker (without any special signal processing) that does anywhere near as good a job of taking you to the concert hall. And that is where you want to go, isn’t it? ‘- Robert E. Greene, The Absolute Sound (Sept. 2008)

Golden Ear Award 2005  (The Absolute Sound): 

‘ In theory, one of the very best ways to make a speaker that ignores the acoustics of the listening room is to have dipole radiation in the bass, but in the treble to have forward radiation only in a uniform but relatively narrow pattern. This theoretical dream was realized some years ago by the Gradient Revolution. With its dipole bass and cardioid forward radiation, it was and is a remarkable success at ignoring its surroundings (and sounding neutral in nearly any environment). The original model has been recently supplemented by a new version with a line-level electronic crossover. This design, which requires bi-amplification, allows crossover adjustment of the bass level to fit room size and acoustics. If high bass dynamic capability is desired and/or the speaker is used in a large room, the bass units can be doubled up—two (or more) can be used per channel. The Revolution, even with extra bass units, is quite compact, but it is a giant in sound quality. ‘ -Robert E. Greene, The Absolute Sound (Feb. 2006)


‘ The Gradient Revolution is a wonderful speaker for those listeners who want their speakers to organize the musical signal as complete, coherent whole, yet who themselves view listening as an activity that requires effort and engagement if one is to extract the value of it. The speaker is honest and fair and represents a distinctive and meritorious approach to reproducing music in the home. One can spend a great deal more and find oneself experiencing a good deal less musicality and honesty. The Gradient should appear on every list of faithful and honest reproducers of music. It's certainly high on my list and thus highly recommended for the active listener. ’- Jules Coleman, 6moons (Nov 2004)

‘ Meanwhile, the Gradient Revolutions, which feature open-baffle dipolar bass, proved their design merit by producing some of the finest bass I heard at the show, and in the smallest hotel room. ‘ -Michael Fremer, Frankfurt Show Report,  Stereophile (Sept 2000)

‘ Viva la revolution! exhorted DO. He found the Revolution, designed to be less room-dependent than ordinary speakers, "quite endearing," although not spectacular in conventional audiophile terms. He decided their greatest strengths were organic wholeness, solid imaging, excellent microdynamic expression, and convincing rhythmic drive. Original review samples turned out to have a broken crossover. JA's Follow-up endorsed DO's enthusiasm for this unprepossessing-looking but neutrally balanced speaker, and he adds that the bass quality and extension are both simply excellent. MF also agrees, adding that the Revolutions work great as rear-channel speakers in a Dolby AC-3 system ‘

- Recommended Components 2000, Stereophile (April 2000)

‘ As it turned out, a superb speaker, the Gradient Revolution, was designed so that in one of its configurations it could work against the wall. How much were they? When told $ 4000 a pair, I may have felt dizzy. But only a little. My decision was helped because I had heard the Gradients at CES. In fact, I had been so impressed with their neutral, transparent sound that I had gone back several times to listen to them. ’ ‘ Soon a pair arrived at my house, and my good-natured wife couldn’t resist making jokes along the lines of  ‘ It would have been cheaper if you’d gone to Vegas and just gambled. ‘ The Gradients spoke for themselves, however. After I hooked them up and played more of those LPs and some CDs, my wife settled into a chair, spellbound. The musicians seemed to be spread out before us. Each note was amazingly distinct. ‘ -David Morrell, The Absolute Sound (Dec 1999)

‘ The Signatures also made my Gradient Revolutions sit up and take notice. Gradient’s designer Jorma Salmi says that given the open-baffle design of the woofers, the Revolutions prefer solid state to tube, and they need an amplifier capable of exerting firm control on the bottom end. In my over 3,150-cubic-foot living room I could not overdrive either the speakers or the amplifier at any level I could stand. A good friend of mine who owns Gradient Revolutions loves Nineteenth Century orchestral and organ music. He bought the Gradients for their neutrality and their (just about peerless) imaging. ‘

-Paul Seydor, The Absolute Sound (Oct/Nov 1999)

‘ As well as the flatness - presumably due to its dipolar design and the effectiveness of its crossover, it meets astonishing +/-1.3 dB limits in-room, from the 32 Hz 1/3-octave band to the 10 kHz band - note the excellent extension, the speakers not starting to roll off until below 30 Hz in my listening room! ‘  ‘ My auditioning of the revised samples of the Revolution confirms Dick Olsher's excellent opinion of this speaker. Its modest appearance and size belie a sophisticated, superbly engineered, high-performance design. Highly recommended. ‘ -John Atkinson, Stereophile (March 1997)

‘ The Gradient Revolutions finally provide an alternative to panel and ordinary box speakers. ‘ ‘ The stereo image of the Revolutions is exceptionally accurate with diffused air around the instruments. ‘ ‘ The Gradient Revolutions are always highly musical in all listening environments! ‘ -Patrick Vercher & Jacques Vallienne, Prestige Audio Video (Oct 1995)

‘ Gradient's research into the final frontier of loudspeaker art - i.e., room/speaker integration - has yielded a speaker that I find quite endearing in musical terms. "The Revolution's greatest strengths are an organic wholeness, solid imaging, excellent microdynamic expression, and a convincing rhythmic drive born out of a pure and quick bass range." "My advice is to give this Finnish delight a serious audition. Its inherent musicality may move you to rise and join the Revolution!‘ -Dick Olsher, Stereophile (May 1995)

‘ Andre Previn's Richard Strauss recording of the Alpensinfonie (Telarc CD-80211) and Mariss Jansons' recording of Rachmaninov's third symphony (EMI CDC 7 54877 2) belong to the absolute highest top when we are talking about natural concert hall acoustics. Listening to these recordings through Gradient Revolutions is of a fantastic experience. The walls simply vanish and your living room turns into the Vienna Musikverein Hall and the Philharmonic Hall of St. Petersburg. ‘

- Peter Johnson & Michael Madsen, High Fidelity, 2/1995

‘ Tangible is the term that most accurately describes the sound staging. The Gradients could paint a more convincing picture of an orchestra playing in real space than any other speakers I have heard. ‘ ‘ I recommend them highly. ‘

- Ken M. Duke, The Sensible Sound, No 54, 1995.

‘ The Gradient Revolution is a remarkable, and remarkably successful attempt to design a speaker that is as free as possible from fundamental defects and that can be expected to perform well in real listening environments. ‘ ‘ But what separates the speaker from the usual High End product is the sheer creativity and originality of its acoustic design. ‘ ‘The result is almost a nonspeaker speaker...And naturally recorded music acquires with the Revolutions a musical realism that is startling. For example, the Rutter Requiem (Reference Recordings RR-57) sounds convincing tonally and spatially to the point of almost dissolving the walls of one's listening room. ‘ ‘ Certainly, they would be on the short list of those that I would consider were I required to give up the Quads. Speakers like this reassure one that there is real progress and creativity in speaker design. ‘ - Robert E. Greene, The Absolute Sound (Nov 1994)