Von Schweikert Audio Unveils VR-100XS Loudspeaker

February 13, 2013


Von Schweikert Audio presents the ground- breaking VR-100XS speaker system. All aspects of its design were approached with the goal of an acoustically holographic listening experience of a live musical event. To achieve this, we have engineered a) an all-new Noise Reduction cabinet construction based on our Triple-Wall constrained layer patent, b) a matched driver array using the same magnesium diaphragm material from woofer to mid to tweeter for coherent timbre response, c) transient-response ‘speed’ matching of the driver array using proprietary servo-controlled filter circuits instead of a typical crossover, and d) room-correcting subwoofer design that eliminates the standing wave phenomena through the entire room. We believe the new VR-100XS is a complete solution, with the most advanced engineering on the planet. Here is why:

The speaker drivers are implemented as a vertical array as in the legendary VR11-MkII. As recording microphones are ‘point sources,’ we have designed a Point Source Concentric driver Array to properly recreate a holographic experience. The initial source of the focal point is the centered tweeter, with concentric arrays of midrange and woofer drivers. On the rear of the tower is a two-way Ambience Retrieval System that will complete an omni-directional spherical-wave radiation pattern.

In each VR-100XS tower, the four -7″ woofers and two -5″ midrange drivers are custom-designed, ultra high speed, non-resonant magnesium-coned units, damped with a layer of ceramic oxide. This cone material is extremely light, rigid, and tonally accurate; the ultimate in transparency. Each driver was designed in conjunction with the other frequency range drivers to insure a coherent timbre and transient match between all drivers. Using linear high intensity neodymium magnet bars, we have greatly reduced back-wave reflections. The magnetic flux density of the ‘motor’ is linearized by the use of copper rings, shorted-turn triple voice coils, and T-shaped pole pieces with copper cladding. These motor developments were patented by our Norwegian supplier and according to our measurements, these drivers have approximately seven times less motor distortion than any other moving coil driver on the market.

The newly designed ribbon tweeter, placed centrally in the array, has both ultra wide frequency response and wide dispersion due to a proprietary wave-guide. The response and dispersion of all the drivers have been carefully engineered to merge into a single, coherent, virtual point source necessary to generate the holographic virtual reality effect. Transient response matching of the drive units, from the 15” magnesium-coned subwoofers up to the 2” magnesium foil/Teflon sandwich ribbon super tweeters is controlled by a proprietary circuit with ‘servo control’ using the drivers’ back-emf (electro-motive force) for sampling of the signal versus driver response ‘speed’ in actual real time. A feed-forward circuit was designed to electrically damp the driver behavior to match each other driver as closely as possible. Of course, we have implemented mechanical Time Alignment as well as phase coherent filter circuits for the best possible image recreation. Needless to say, each driver is wired in correct ‘absolute’ polarity. Since our matched drive unit diaphragms and complementary filter circuits ensure a complete mechanical and temporal coherence, the tonal accuracy of the VR-100XS is stunning.

VSA research has found that any spurious vibrations in the system can and will compromise that sense of holographic realism all audiophiles seek. As a result, the cabinet is massively constructed using a new version of the VSA triple- wall damping technology and complex internal bracing. This has resulted in an acoustically inert tower, each weighing over 460 pounds. Even with this elaborate construction, the visual appearance is slender and graceful, complementary to any home. The main towers are 1ft wide x 6ft tall and are available in many high quality automotive finishes.

The external sub-woofers, the “XS” of the system, are also an all new VSA engineering solution. They are designed to be placed at or near the rear of the listening area and are aimed at the main towers. Our new patent pending technology will eliminate room response anomalies when integrated with the already outstanding bass performance of the VR-100XS towers. The XS subwoofer amplifiers have Time Delay controls to adjust the response for the room dimensions and can be adjusted to compensate for standing wave modes in any room, no matter the size. The elimination of standing bass waves in the room is not achieved by equalization in the subwoofer amplifier, but is achieved by acoustical cancellation of Eigentones throughout the room, without any digital implementation of any sort. This technology is based on the averaging of pressure at low frequencies at all places in the room; with the combination of four sources of bass below 120Hz (the two main towers and the two rear subwoofers), the bass pressure will vary no more than 1.5dB! Contrast this figure with the normal deviation of bass which is likely around +/- 12 to 18dB in any given room! Our cancellation technology has been verified by Dolby Laboratories in conjunction with Lucasfilm THX (where I was once employed).

The degree of the resulting bass realism is an industry first and extends down to 10 Hz, but most importantly, has transient response speed and clarity that equals the response accuracy of our woofer and midrange drivers. The supplied subwoofer amplifier is designed and built in the USA; it supplies over 1,000-watts r.m.s. into each of the four voice coils of our Super Duty High-Speed Infrasonic Subwoofer driver. With a 60 pound (that is not a typo) motor and four -5” voice coils configured in Push-Pull operation, the 15” magnesium cone with a 3” total excursion potential has the lowest distortion and quickest transient response speed of any subwoofer on the market. With a 3” thick Triple-Wall Noise Reduction cabinet weighing almost 200 pounds, the sound is extremely solid, tight, and coherently matches the ultra-fast 7” woofers of the Main Towers. A Signal Sensing Cable made by Delphi Aerospace is supplied to connect the Main Towers to the Sensing Inputs of the XS subwoofers (the subwoofer signal is not sent from the preamplifier, but from the main speaker). In order for the subwoofer to “follow” the main woofers, we have implemented a ‘servo-controlled’ feedback loop from the main woofer’s back-emf (electro motive force) output to ‘tell’ the 15” woofer how to react, in terms of speed and tonal quality. This is a fairly new technology, invented by us several years ago for the dB-99.

Even the rear-facing implementation of the VSA “GAIN” Ambience Retrieval System breaks new ground, as we have engineered a solution to recreate the desired dispersion pattern of an omni-directional speaker system. This requires a bipole implementation of a rear wave that will combine with the front wave to generate a ‘side beam’ of sound to enhance the ‘openness’ of a live performance. Using both a 1.25” dome midrange and an additional 3” ribbon super tweeter, the new 2-way rear-firing design operates from 1,5kHz to 100kHz. The 1,5kHz frequency was chosen by examining the polar response of the front driver array’s response at 90-degrees off axis. When both the front and rear driver arrays are measured, the speaker behaves as a quasi-omni speaker, similar to a cardiod pattern as in recording microphones. This new “HGAIN” technology couples with the front drivers, completing the you-are-there holographic experience.

Many custom internal components for the VR-100XS were developed by industry leading suppliers and manufacturers in consultation with VSA with multiple rounds of prototyping and evaluation. No detail was too small to be tested and optimized for this new reference system. Master-Built Single Crystal copper wiring from Delphi Aerospace is used internally, with twin pairs of WBT Signature NextGen platinum binding posts available for bi-wiring or even bi-amping. All internal crossover parts are supplied by Deulund, Jensen, V-cap, Mundorf, and Clarity Cap. Inductors are made from Single Crystal ribbon foil copper on midrange/tweeter circuits and 1,000-watt steel laminated transformer types for the woofers. All resistors are Mundorf metal film.

The VR100XS is a no-compromise product that offers the passionate listener an unparalleled experience of a live musical event brought to your listening room. Full specifications and photos will appear soon. Relevant specifications at time of this publication are: $145,000 for the 4pc system consisting of two Main Towers and two XS subwoofers with 15” drivers and 1,000-watt amplifiers. Main tower is 6 ft tall x 1ft wide x 30” deep with a weight of 468 lbs uncrated. The XS subs are 176 lbs @ 24” x24” x 24”. System sensitivity is 90dB, impedance is 4-ohms, recommended power rating is 50 watts to 1,000-watts, frequency range is 10Hz to 100kHz. Main Towers have Autoformer Level Attenuators for front Tweeter and Rear Ambience Level.

Source: Press Release