GRADIENT R-5A - THE NEW REVOLUTION
Gradient Revolution series has been 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. The first version of the Gradient Revolution was introduced in 1993. The new active version, the Gradient R-5A, continues the revolution with new features.
The bass part of Gradient Revolution loudspeaker consists of two 12" 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 20Hz 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. 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 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.
ONE POINT SOURCE
The new Gradient Revolution is utilizing our latest coaxial technology. A 176mm pre-coated reed paper cone handles frequencies up to 2.5kHz. High frequencies from 2.5kHz to over 20kHz are reproduced by a 25mm Al/Mg-dome tweeter placed at the apex of the midrange cone. Such a point source is generally accepted as an ideal sound source for its excellent phase and amplitude response. The end result is an extremely accurate, stable and three dimensional soundstage.
SPHERICAL ACOUSTIC RESISTANCE ENCLOSURE
To minimize reflections from the speaker cabinet, the coaxial element is mounted in a spherical enclosure. The sphere is an ideal form with no structural interfaces and discontinuities. Symmetric spherical housing leaks “anti sound” from the opening behind the sphere, cancelling backward radiation and early reflections from the surfaces behind the loudspeaker. Thus 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. Special attention has also been taken that the radiation patterns are consistent at all frequencies. In a nutshell: the room influence to the sound remains very small giving the new Revolution a very similar sound characteristic in many different rooms.
FLAT ENERGY RESPONSE
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 POSSIBILITIES FOR ROOM POSITIONING
Gradient Revolution can be positioned in the room like a panel 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 several 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.
ACTIVE CROSSOVER WITH AMPLIFIERS, GRADIENT XO-AMP
If you listen to the bass section of the Revolution alone you will be surprised to find how little information there really is under 200Hz. However the quality and quantity of this information affects strongly to the subjective listening experience. Too much bass will decrease the accuracy and deteriorate the feeling of space, too little makes the sound thin and tiring.
The real low frequency properties of a sound recording will be reproduced most convincingly by a dipole bass system giving the radiation pattern of eight. You can easily hear the minute tone nuances and follow the bass lines. When compared to the conventional closed box or bass reflex systems you will get the same sound pressure level at only one third of acoustic energy. Thus the room colouring effects are much less annoying and your neighbour will hear less of your bass lines. Otherwise excellent system the dipole bass has one drawback, how to get high volume and how to reproduce the lowest notes. Gradient has solved these problems in the active crossover offering unprecedented possibilities to fine tune the bass response both in quality and quantity.
The new Gradient Revolution comes with Gradient XO-AMP, an active crossover and power amplifier based on the high-performance Hypex Ncore®-technology. Features like extremely flat frequency response irrespective of load impedance and practically frequency independent distortion behaviour make the power amplifier one of the very best in the market.
TRUE DUAL-MONO DESIGN
The Gradient XO-AMP has four power amplifier modules, two per right and left channel. The channels have completely separate switch-mode power supplies and signal-return paths making the maximum signal separation with minimum crosstalk.
BASS LEVEL CONTROL
The level of the signal, feeding the bass amplifier can be adjusted continuously by a trimmer adjustments at the back of the unit. The adjustment range is +/- 10dB for both channels separately. According to the personal taste and listening room acoustics the bass is easy to adjust. Once found the correct balance, there is little need for further adjustments.
The Gradient XO-AMP is equipped with balanced Neutrik XLR - connectors. The speaker connectors are professional Neutrik speakON connectors. Speaker cable lengths can be selected by the customer when making the order. If one wish to use an external power amplifier, for example valve amplifier, for the midrange and treble, the XO-AMP has a line level high frequency output for the purpose.
MANY USEFUL FEATURES
Gradient Revolution is stylish whether the woofers are directed to the side or front. The easy-to-connect speaker connector is located on the bottom of the speaker, from where the speaker cable can be routed freely in the desired direction or even directly to the floor structures if one want the cable to be out of sight. The new Gradient Revolution is designed and manufactured in Finland. Needless to say that special attention has been paid to the quality and finish of all materials.