The short story
Music appeared in the first weeks of my life. On the one hand it was something natural for me and on the other something essential just as food, drink or sleep. Over the course of the years, the activity of listening to music became my great passion. What is more, I started to pay my attention more and more to the quality of sound. In October, 1996 in Warsaw there was the only concert in Poland of Michael Jackson. The concert had so perfect sound system that I must have held my breath in amazement. That event constituted the turning point in my life. I realized then how faulty and imperfect my musical player equipment was.
After coming home in a state of excitement, I wanted to listen to the same songs all over again in order to feel that atmosphere one more time. However, after a few sounds my disappointment rose flagranly! The speakers that I had at that time gave out something… indeterminable. These average speakers were produced by some worldwide company and, therefore, I expected much more. At that time I realized that the speakers did not sound as perfect as I wanted them to. I was the teenager then, so I could not have been able to afford to buy more expensive and equipped ones. In a result, the thought crossed my mind. The idea was to create such speakers that could give the joy of listening to music. What is more, these speakers should give out such sound like this one I have heard during that concert and they should not cost a fortune.
The process of designing the speakers turned out to be very complex and labourious process which is full of unpredictably achieved results and moments of doubt, even despair.
To create speakers, that would be good in sound and appearance and that I would be proud of, lasted nearly three years. I named these speakers Altair which means “the flying eagle”. One of the stars in the sky is named Altair. In that way I was able to combine my two great passions which are music and astronomy.
The Altair speakers were improved many times and their sound was transformed few dozen times. I was in search of something undefined which I felt my speakers lacked. The process of creating these speakers showed me the complication and extensiveness of the process of designing the speakers’ cabinets. After many months of designing, testing many various alternatives, listening to again, simulating on a computer, the speakers came into being. Their main characteristic was that they gave some semblance of intercourse with live music. After so many years of gaining experience in designing, I am now aware of my first speakers’ imperfection.
These Altair speakers enabled me to learn how design the speakers efficiently. The only pair of them was created and they work till now.
Few years along I designed more or less successful speakers’ sets for my friends and acquaintances. Thanks to that I have been more and more experienced in designing. In 2007 an acquaintance asked me to create the monitor of close field. Its purpose was to be used in his recording studio at home. In the final phase of the project my friend – audiophile visited me. I asked him to assess its sound. He was very astonished by the sound and encouraged me to create the speakers for audiophiles on the basis of these monitors. For the reason that there were many perpendicular cabinets all over the shops, I decided to design a project which would stand out from others.
Since I was child I was fascinated by science fiction films, the future technology and stars. One of the ground-breaking movies in the history of cinematography is Stanley Kubrick’s ‘A Space Odyssey 2001’. The very important part of this movie was mysterious monolith made of unknown material. It became the inspiration for my project. So called Proxima came into being. As it turned later out, its name was metaphoric.
The Proxima means ‘the first’. As my first project the Proxima speaker was assessed by the specialist magazine and, surprisingly, it was awarded by ‘Best Product 2008’award in the highfidelity.pl magazine. Furthermore, as the first of my projects (exactly Proxima2) has received elaborated in years by myselfBAD and SGP systems which are described later in the text. Finally, as the first of my project it released from Poland. Also as the first received the flat multilayered cabinet and became the precursor of speakers’ models which Divine Acousticsoffers nowadays.
Proxima project was originally created as the monitor of close field which provided quick and impulse sound with least possible distortion. However, that idea evolved into unique in design speakers’ set. Nevertheless, that set is encased with the closed up cabinet. Thank to the closed up cabinet, the set takes advantage of its virtues, but, simultaneously, takes disadvantage of lacking of bass-reflex’ features. The following sets, so called Electra and Antares cabinets, were equipped with bass-reflex and based on applied in Proxima systems.
During the initial years of designing the speakers’ crossovers, I used computer software. With the usage of that software I could have carried some simulations out. What I have observed was the fact that the results achieved by computer and the sound which I heard did tally. I had to spend many hours in concert hall, thousands of hours listening to music and, therefore, exercising the hearing. As a result I have worked out the scheme and the algorithm for designing cabinet sets. I have not used any computer software to design crossovers since the time of Proxima set. The sound of every cabinet model constitutes the result of few months’ hearing-through-tests and the selection of components which harmonize with each other creating the final effect.
Divine Acoustics speakers constitute the coexistence of modern design and hand-made carpentry. The remarkable visual impression is achieved through the combination of beautiful figures of exotic wood, leather and the slenderness of the floorstand cabinet.
To achieve such an effect the ‘golden division’ – in other words gold proportion or divine proportion (lat. divina proportio) – rule was taken into account during the process of designing the shapes of all kinds of cabinets. The golden division is derived from antiquity and since then the exceptional esthetic effects are ascribed to it. Designed in that way shapes possessed harmony and were described as beautiful.
The idea of Divine Acoustics’ designs was to create not only an equipment to the sound reproduction, but, above all, an elegant shape which remains in harmony with the interior décor and becomes its adornment.
The cabinets of the Divine Acoustics speakers are designed in CAD environment. They integrate the sui generis look with elements which are required to gain the proper sound of mounted speakers. During the process of designing the three dimensional model, precise technical drawings and templates for all of the elements are made. The templates ensure the repeatability during the production of all units.
Peculiar resonances of the cabinet are damped using multilayer walls built of different dampening feature materials – in every cabinet there are at least 6 different structural and finishing materials. At the bass speaker height the cabinet is reinforced by using steel bars which form the rim. The high frequency speakers are mounted into the main cabinet with the usage of damping layers.
Resonance of the flat cabinet
According to the Helmholtz’s rule of resonator, which describes working of the open speaker cabinets, the frequencies which are radiated by the opening in the cabinet are being displaced in phase against the radiation of the speaker. This displacement increases with the decrease of frequency and is approaching the value of 180 degrees and, thus, is cancelling the radiation from the speaker. The phase displacement of the resonance frequency of the cabinet – where the bass-reflex exhaust works at maximum level – accounts 90 degrees in comparison with the speaker’s radiation. The best placing of the bass-reflex exhaust, which gives the lowest frequency response and the lowest possible phase displacements, will be by the 90 degrees to the speaker.
By placing the bass-reflex exhaust at the bottom of the speaker’s cabinet that kind of radiation rule may be achieved. Additionally, that kind of placing of the exhaust gives the cabinet the ability of less excite while is placed near the wall of the room and also the distance between the exhaust and the nearest reflecting surface (floor) is always constant.
The process of selection of the suitable bass speaker – with proper mechanical, electrical and sound qualities – is the key to gain the proper final sound of the speaker. There are many speakers in the world which differ in parameters, kinds of used materials and prices.
During many hours of hearing through tests and as the experience in designing was being achieved, the sets of speakers’ parameters were determined in Divine Acoustics workshop. These parameters are very important for receiving dynamic and natural sound of the speaker set.
The speakers, which are applied to the cabinets, possess diaphragms with appropriate relation of vibrating mass (Mms) to the efficiency (SPL) and the basic resonance (Fs). Many companies produce speakers with very low resonance of diaphragms, however, in such case the diaphragms are too heavy, or the efficiency of such a speaker is too low. In consequence, the speaker is too quiet. The speakers chosen by Divine Acoustics possess the relatively high efficiency (above 88 dB), the small mass of diaphragm and the resonance below 40 Hz.
Parameters mentioned above are connected with the following: combination of total Q factor (Qts) of the speaker and the speaker’s equivalent volume (Vas). Many speakers possess the total Q factor which is suitable for the bass reflex cabinet; however, their equivalent volume often is very high. Thus, the designed cabinet must have the very great volume and, consequently, the light diaphragm of the speaker must move the great amount of air in resonance system. Such process is not in favour of gaining the quick and impulse bass. Therefore, the speakers which are applied by Divine Acoustics have the proper combination of required volume of the cabinet and the mechanical susceptibility. This combination enables to achieve very efficient impulse characteristics.
When dealing with selection of the appropriate bass speakers, the most important criteria are their parameters and sound. Therefore, neither the price, nor the trends in using the speakers of company X or Y do constitute the main criterion for selecting the speakers. Moreover, not every expensive speaker possesses the proper parameters or not every speaker, which does possess the proper parameters, sounds good.
High frequency speakers used in the Divine Acoustics designs contains very light silk domes.
Electrical circuits – the crossovers
The crossover constitutes one of the most important elements of the speaker system and also the element which demands the greatest amount of work during the designing. Properly selected electrical schematic, configuration and layout of the elements on the board as well as its quality and connecting wires – all of these factors influence the final sound of the speakers set. The well-matched value of the elements forces the time and phase coherency of the transducers and influence its musicality, felt speed and punctuality of the sound.
Properly configured crossover plays the key role in harmonizing of the speakers with each other and, thus, they create homogeneous entirety just as if they become a single transducer which reproduces the entire frequency spectrum.
Listening tests, which were carried out, have proven the fact that making connection with the amplifier using single-wiring with the higher quality speaker cables gives better sound’s result than bi-wiring using lower quality speaker cables. Due to that fact all Divine Acoustics’ speakers hold a single connection plugs allowing single-wiring.
The crossover configuration is not just the division of the frequency response and phase arrangement of the speakers. It is also very important for the amplifier distribution of the power which is picked up by the transducers. The correct distribution of the power coming from the amplifier to the individual transducers allows gaining the significant volume of the undistorted sound with full dynamics range and simultaneously reproducing of full frequency response with very low volume. That kind of the crossover configuration facilitates driving the speakers even by the amplifiers with the minor output power.
The crossovers designed by Divine Acoustics are second order passive filters. Thanks to the additional circuits, which are correcting phase and impedance for both speakers in two-way speaker system, elimination of the series and parallel resistance elements in the filter path for high frequency speaker has been made. It improves the micro dynamics and nuances of the high frequencies considerably with coincident preservation of the proper ratio to the middle frequency range.
The crossovers are made of high quality elements. All capacitances are Jantzen-Audio polypropylene capacitors, which are commonly connected into pairs containing different sounding Z-Superior, Z-Standard, Cross-Cap and Z-Silver series. Variety of used capacitors is matched during listening sessions and influence significantly to the final sound quality of the speaker system.
All of used coils are made of oxygen free copper (OFC), they are accurate measured and paired. All the crossovers during the assembling are extensively verified of all values and the quality of joints. After assembling the comparison with the comparative crossover is made. It assures the repeatability and high quality of components mounted into
Divine Acoustics speakers.
All joints are made using soldering alloy which contains tin and copper and it is free of lead (Pb free).
Divine Acoustics products are made in a small manufacture in Poland. Starting from the first sketch, through all design works, carpentry, upholstering, final parts assembling, to the final product all activities in Divine Acoustics workshop are made by hand.