Making top quality speaker sets with the intention to present them as uncompromising designs, the designers are trying to impress people with innovations. As a result, they introduce as many proprietary solutions as possible (which then frequently turn out to be empty slogans) or forcing open doors, often bringing more damage than benefit. ESA does not announce a revolution in the speaker technology; what it promises is only perfect sound based on proven principles, systems and materials. A constant foundation of all ESA designs is careful alignment of the best components that can be used within a specific price limit, with consideration given to all interdependencies typical of the always complex nature of a speaker set.
Also Credo 3 Illuminator is based on this foundation. This set, however, rises above all other two-and-half-way systems by using the state-of-the-art, fantastic Scan-Speak Illuminator transducers.
Two-and-half-way loudspeakers combine many noteworthy advantages. Based on high-quality transducers, they bring together good parameters and good sound with a comfortable cabinet form which kept the moderate width of the front wall owing to elimination of the large woofers.
Three-way systems, boasting of specialized woofers and midrange drivers mostly lose competition with Credo 3 Illuminator in every aspect. The Illuminator midwoofer maintains the very low level of distortions throughout the band as well as at high amplitudes and powers, which allows effective and accurate processing of low frequencies while keeping the top resolution of the midrange frequencies. These possibilities are a result of a combination of sophisticated design features unprecedented in any other speaker: powerful neodymium motors with under-hung voice coil and a basket moulded into a perfectly aerodynamic shape. The advantage of cellulose cones is that they are good in dispersing resonances, which is the effect of their structure (different length fibres arranged in various directions); usually cellulose cones are sufficiently rigid and guarantee good results even without any special efforts. In the Illuminator, the cone is made up of two layers in which the wavy overpresses are “phase-shifted” in relation to one another, which gives the whole cone special stiffness with moderate weight and particularly effective damping of the standing waves.
A pair of 18-centimeter Illuminators has a very high potential in the low tone range, however to obtain top characteristics it requires appropriate alignment of the bass reflex cabinet. As research has shown, no conventional system with a bass reflex will work here, as it forces us to use either a very long tunnel, which is troublesome and enhances parasitic resonances, or to reduce the opening area, which in turn causes compression and turbulence noise. In this situation, the best solution – already used previously by ESA – is to install passive radiators. At the back wall in the Credo 3 Illuminator we have placed as many as four 18-cm passive radiators with very large excursion (these are famous “coal” Scan-Speak). Each speaker drives two passive radiators, creating a resonance system aligned perfectly in every respect – in the best volume, to the optimum frequency – and ensuring very good low bass reproduction and excellent impulse response. Freedom of operation of this system is not limited by the opening size; the system is also less susceptible to transmitting standing waves from the cabinet. To reduce them even further, the cabinet has been divided into two chambers (the partition comprises two components set at an angle of 90° towards each other and 45° towards the horizon). The chambers are of identical volume and with identical passive radiators pairs; they are aligned identically to ensure perfect phase cohesion of the two subsystems, and thus the best bass effectiveness and dynamics.
The operating principle of the two-and-half-way system is the differentiation of filtering frequencies by midwoofers. We have again focussed on minimizing phase shifts between two speakers, including shifts above the lower woofer’s filtering frequency to avoid attenuation of processing characteristics in the range of several hundred Hz, occurring with (too) early damping of the lower speaker when it is treated only as a subwoofer. Operating range of this speaker up to 500Hz, preferred by our design engineers, allows compensation of the attenuation occurring in this range in structures approx. 20 cm wide. Also the slope of low pass filters has been adjusted to simultaneously ensure the optimum damping of each speaker and maintain their close phase characteristics. Owing to this, very good directional characteristics are obtained in the vertical plane; a listener located in a quite broad field of the optimum listening spot, even from a small distance experiences a very stable and clear image of the sound stage, with well-balanced tone characteristics of beautifully saturated lower registers. Sound sources are properly located but are not only points on a map; they represent reliable and natural sizes of instruments.
Space, respiration, accuracy and subtlety can be credited largely to the tweeter. Originating from the reference R2904 ring radiator, the new R3004 model has a six-segment neodymium magnetic system giving it power adjusted to the effectiveness of the 18-cm Illuminator pair. Owing to this, the crossover network needs no damper, no resistor, the quality of which would need to be ensured. While in R2904 characteristic on the band edge is slightly rising, in R3004 it is perfectly plane. This gives the sound the feature of pure neutrality, maintained by the alignment style of the entire set. To maintain distortions at a record-low level offered by Illuminators, all coils are air coils, and the large coil in the woofer has been wound using a 2-mm wire. Its resistance is still similarly low to the resistance of the smaller coil in the midwoofer’s filter. All condensers are made of polypropylene and, like the coils, are selected with 0.5% tolerance. Binding posts are original WBT products.
Outstanding speaker structures frequently have an awe-inspiring exterior design. It is not, however, a feature exclusive to them – poor quality loudspeakers may equally well deceive with showy design and seemingly spectacular sound. Therefore, when designing top quality loudspeakers one must find his own formula. Making the form complex is unnecessary; it can be even simplified, without becoming primitive. One clear, unique and state-of-the-art feature can be introduced to define the entire silhouette. First of all, one should take care that the form in a clear and dignified way follows the contents. The sloped front wall of Credo 3 Illuminator calls upon the famous concept of “time equalization”; out-of-parallel front and back wall and the accompanying special setting of the partitions inside the cabinet help in damping the standing waves. Slight spread of the midwoofers sets them in optimum positions considering waves reflected from the floor causing amplification and attenuation of characteristics; in Credo 3 Illuminator they will counterbalance each other.
The cabinet has been assembled without traces of wall connections, which required top precision, state-of-the-art machines and the hand of an experienced joiner; the case is similar with the perfect veneering (available in a broad selection of natural veneers) and varnishing.
High effectiveness, convenient impedance, broad and equalized band, neutrality, precision and dynamics, natural representation of the stage, saturation, plasticity and articulation of midrange region, bass impressing with its spread and control, minuteness, freedom and air of high tones – Credo 3 Illuminator really combines all these. For rooms of 20 to 50 meters, for 50-300W amplifiers, for the music you like. With Credo 3 Illuminator you will like it even better.