Акустические системы Sonus Victor SV-350S

Author: Nickolay Yefremov (http://salonav.com/)
May 2017

I’m intentionally refraining from a ”signature acoustics” introduction, as any project has its creators and it doesn’t matter how many of them – the result is what’s more important. But today’s case is exceptional. Systems that we are about to listen were not created by a team of specialized experts, but by one person that had set himself specific objectives with understanding of how to achieve them.

We are already familiar with Sonus Victor acoustics, but the person standing behind this serious project had remained in the shadows. This is our former compatriot Victor Porkalov, who has lived in Italy for over 25 years. In 2011 he founded his own Sonus Victor company in Verona where he simultaneously performs the tasks of an engineer, designer, redwood craftsman and marketing expert. This kind of arrangement makes it convenient by not having to reach endless agreements, and upon deciding to create something, Victor develops a project and launches its implementation with a small group of assistants.

When listening to a higher model SV-400 I was confident that it was really the edge – both from the engineering point of view as well as by the uncompromising implementation. But as it turned out the author himself wasn’t completely satisfied with the results and had ventured a new project – a system of same dimensions but with a further precise, refined and more lively sound. The remainder was to translate these terms into a technical language and procure materialization.

Accordingly, during the SV-350S’s creation main efforts were aimed at decreasing all types of distortions, including phasic. For defeating resonance and noise the cabinet has double layers: thick MDF sheets joint with braces in the inside and solid Italian walnut on the outside. Purely handmade highly skilled job, therefore you won’t find any openings, skews or any other even minor flaws in the finish. The front panel is traditionally narrowed towards the top that provides for interference reduction between mid and high range frequencies. Each speaker weights 75 kilograms.

 

The main difference from the 400’s that catches the eye is multiple concentric ridges on the external surface over the mid-range diffusors. This is a relatively complicated to implement and costly way of defeating flexural distortions that occur at high volumes. Or as the engineers say - expanding the piston’s range whereas the diffusor itself has a completely rigid membrane. In our case the distortions are minimal and the weight of the moving parts practically do not increase. The used material is the same as in other Sonus Victor speakers – impregnated cellulose. But their suspensions are different as made from foamed polyurethane which also positively affects the speed of response. The caliber of mid-range speakers is an impressing 200mm.

As well there are two low range paper woofers working in a sealed enclosure. The choice is clear, comparing to open invertor cases, as it provides for a faster and clearer bass with no sacrifice in sound power deepness – the enclosure volume allows leveling down the low range to 21Hz, as one of a large subwoofer. Although why “as one of a”? Drivers are filtered very low, each with its own crossover but at the same frequency. Overall the system is four-line.

This is the part that requires clarification. Four lines on their own shouldn’t be perceived a significant achievement – with Victor’s budget the number of speakers could be higher. But whether it would benefit the sound depends on the developer who must take into account a number of contradicting factors. The main one is phase (i.e. timing) conformation of lines with obtaining the required total directional diagram. These tasks are resolved by selecting (in our case – manufacturing) speaker heads with the desired characteristics, their allocation on the front panel and fine-tuning the separation filters. Victor keeps his scheme in secret but, nevertheless, he has kindly provided a photo of the circuit board with the installed elements.

As you can see it’s an impressive in size module with symmetrical allocation of four RLC chains. The boards are soldered by hand, the elements, particularly the Mundorf capacitors are carefully selected by matching pairs. Wiring within the case is made with RF cables composed of many insulated threads that benefit by providing minimal losses on high frequencies, therefore often used in communications equipment.

A pair of one inch sized twitters with impregnated textile domes work in different frequency ranges. Short horns, in which they are imbedded, tends to correct the directional diagram. Overall, it is formed by symmetric allocation of the mid-range and high-range heads in relation to each other. This is a slightly adjusted d’Appolito array providing, as known, for a broad opening in the horizontal plane. It is important in our case as the height of the systems is 1,5 meters and if the allocation were different we should have being listening to them standing. By the way, specifically due to this factor the d’Appolito principle is used in the central channel speakers, but with a twist of 180 degrees in order to cover as much of the horizontal area as possible.

Generally speaking, the configuration of our system was 5.4.0 and we were listening to the SV-350S’s as in stereo, as well as in place of front-side speakers of a certified Auro 3D setup. There was a lot of equipment involved and all of it has being carefully selected to obtain the most impressive sound results. Literally impressive, though not deafening as in some stage installations.

So, first we watched “Jurassic Park 3D” on a Blu-Ray in Auro 3D. Noteworthy, there wasn’t a separate subwoofer within the system, but the bass was so powerful that the couch rocked that we were sitting on. Moreover, these were not only LFE special effects but a surprisingly rich sound range up to an ultra-low-range spectrum with all the sounds absolutely realistic and recognizable. Sound field information was as well reproduced very precisely, the front field represented a realistic wall of sound composed of a mass of finest fragments. Such nuances along with booming dynamics is a practically impossible combination as the latter requires the acoustics to have mutually contradictive characteristics. The diffusors of the SV-350S’s are able to react to the most subtle changes in the input signal along with having such an impressive size and to produce peak amplitudes without compression. The sound turns out to be thorough, balanced and even at peak volume levels all timbres remain clearly recognizable. The sounds of nature, musical samples from the Auro 3D demo – everything sounded as from a very expensive home theater installation with a properly matching special effects channel.

In regards of music in stereo the situation was even more interesting: you have huge wooden towers in front of you, but the sound is like coming from the wall behind them. The sound scene is coming out of there to the front line and several fields remain in depth forming a clear fixation of virtual images. And the detail level that I have mentioned above was not limited to a formal representation of the recording’s nuances – in contrary they have formed into a concordantly completed musical painting. Not a single irritating pitch, whatever disk inserted into the player.

Later on, we have conducted the second round of auditions of the SV-350S in significantly more challenging conditions – at the Hi-Fi & High End Show (http://www.hifishow.ru/). There the system demonstrated truly fantastic dynamics, pumping a 100 square meter demonstration hall with high ceilings. And again, the same effect – utmost level of sound accuracy on any volume level combined with a comfortable sound delivery. For demonstrating the timbral accuracy of the acoustics, as well as last year, an interesting experiment was conducted. Playing back violin from a vinyl LP player (Techdas Airforce 3 with vacuum disk hold and air bearing) with simultaneous live violin performance by the famous Andrey Chestyakov. This is when it became obvious that the system does not output synth sound or simplify timbres. Due to the richness of the spectral composition for conveying string vibrations and the “rosin” feeling, both sound sources were so close that it was difficult to distinguish between a recorded and live violin. High harmonic accuracy, perhaps, isn’t something unique, but this to be present in combination with power blasting dynamics is extremely impressive and quite rare in reality.

Such nuances along with completely stunning dynamics is an almost impossible combination, as the acoustics should have mutually exclusive characteristics in order to achieve this.

It became obvious that the sound of the acoustic system does not produce unnatural artificial sound or timbre simplifications.

Configuration: 6 speakers, 4 lines || Frequency response 21 – 30000 Hz || Nominal/minimal impedance: 6/4 Ohms || Sensitivity: 91 Db || Recommended amplifier power: 30 – 350 Watt || Enclosure: solid walnut || Dimensions (with stands): 340 x 440 mm || Weight (1 pcs): 75 kg || Price for a pair: 36000 €

Original release