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von schweikert audio VR-2 loudspeakers - A Musical Bargain as reviewed by George Pappas
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I have a lot of respect for Von Schweikert loudspeakers. I remember visiting the Von Schweikert room at an audio show in Toronto, many years ago, just after closing time for that day. The speakers were a pair of the original VR-4s, the first ones produced under Von Schweickert's name. The Von Schweikert people were attempting to optimize the sound. At one point, they tried a different set of speaker cables, and about five of us sat down to listen. They played a classical piece that lasted about ten minutes. At the end, all of us stood in silence for about 45 seconds, so moved were we by the quality of sound. Right then and there, I became very impressed with the talents of Albert Von Schweikert. When I unpacked the VR-2s, I was immediately struck by their excellent finish. The VR-2s have a suggested retail price of $3000 per pair. My sample had real maple veneer, and for this kind of money, the quality of the cabinetry was outstanding. I was also impressed by the way the speakers were packed. They were double-boxed, with heavy-duty cardboard that protected them very well. Each speaker has three drivers on the front: a soft-dome tweeter on top, a midrange/woofer in the middle, and a woofer on the bottom (actually, a subwoofer that augments the midrange/woofer at the lowest frequencies). There is also a rear-mounted ambience tweeter. There are four binding posts, for bi-wiring, on the back of the cabinet, and something unique—a volume control for the ambience tweeter, which is continuously variable from totally off to maximum volume. This is an excellent idea, as it allows integration of the ambience tweeter with the main drivers. One quibble I had with the VR-2s was the close proximity of the two bi-wire binding posts on the rear panel. There is very little vertical distance between one set of posts and the other, making it difficult to install spades. At the bottom of each speaker cabinet is a hollow chamber, which can be filled with either sand or (preferably) lead shot to mass-load the speaker and to control cabinet resonances. This is an effective way to make an inert cabinet at a reasonable price. Von Schweikert recommends that the chamber be half-filled with 50 pounds of lead shot. He says that filling it halfway will give 85 to 90 percent of the improvement gained by filling it all the way. He told me that adding more shot will tighten the bass even more, and slightly reduce the bass warmth. The VR-2s are supplied with spikes that can be installed in their attractive, black, wooden plinths. Von Schweikert recommends that you experiment with the placement of the loudspeakers before installing the spikes. The reason for this is that if you move the speakers by rocking them on the spikes, you will dislodge the spikes. Von Schweikert told me that he has redesigned the spike fasteners, making them more secure, and that this change will be put into production soon. Von Schweikert designs his loudspeakers to radiate sound like a microphone in reverse. He calls this the "Global Access Integration Network," and he was awarded the CES Engineering Award for it in 1996. The company website (www.vonschweikert.com) states that, "this crossover design and driver radiation pattern allows the speaker to radiate a ‘bubble' of sound, instead of a narrow beam, allowing 3-D imaging over a very wide space. No more trading chairs for the ‘sweet spot'. Combined with the rear firing Ambiance Driver for spatial depth, the VR speakers reproduce sound that is incredibly real." 3-D is exactly how these speakers sound. When properly set up, they produce an extremely open, spacious, holographic soundstage. This requires careful adjustment of the rear tweeter. The idea is to have the loudspeaker radiate equally in all directions, like a sphere. When the setup is correct, the off-axis response of the drivers closely matches their on-axis response. This greatly eliminates frequency nulls and peaks, which are caused by reflections from the walls, floor, and ceiling. The crossover is attenuated at 24dB per octave—with acoustic, not electrical, slopes. On his website, Von Schweikert states, "Proprietary circuits form steep 24dB acoustic crossover slopes at specially selected frequencies without the penalties of induced ringing and excessive phase delay. These slopes are necessary to limit lobing effects and non-linear off-axis response, and actually enable the consistent phase behaviour necessary between drivers. The architecture of the circuitry resembles first and second order filters combined with zobel conjugate compensators in parallel. By using a minimum of high quality parts in series with the drivers, the sound remains transparent, yet the control over phase and amplitude can be corrected with the paralleled zobel circuits." The VR-2s are very easy to drive. Their impedance curve varies from a low of 8 ohms in the bass and treble to a high of 15 ohms in the midrange. This is a very smooth curve, making it possible to drive the VR-2s with almost any amplifier. Nevertheless, the VR-2s enjoy the power and control of higher-powered amplification, specifically my 200-watt-per-channel Counterpoint Solid 2A MOSFET amp. The woofers are loaded by a unique method that Von Schweikert calls the Triple-Chambered Hybrid transmission line. On his website, he states, "Many non-engineers confuse the transmission line speaker with the older design called a labyrinth; while it is true that several companies use the labyrinth design to achieve a transmission line, a labyrinth is not necessary to achieve true transmission line performance. What defines a transmission line speaker is a non-resonant enclosure, with highly damped impedance peaks. The transmission line in the VR-2 uses custom-engineered woofers with suitable Theile/Small parameters for a tuned pipe/short-line with 100% stuffing density to eliminate cavity resonance and damp the impedance peaks of the drivers. Three separate woofer loading chambers using the Distributed Resonance principle: one highly damped chamber for the upper woofer, a large chamber for the second woofer utilizing 30% less density than the first chamber; the third chamber is formed by a combination of the two separate chambers; here is where we place the exit port tube. Note that these chambers are not formed by a section of labyrinth; they are formed by the inclusion of stuffing blankets." The design is claimed to have very tight yet extended bass response, and boy, do the VR-2s produce just that! The bass of these speakers is just incredible. The quoted frequency response is 25Hz to 25kHz, -3dB. This is exceptionally good low-end response, and absolutely remarkable for a loudspeaker that uses two 6½-inch drivers. I was astounded at the depth of bass they could produce. The low end sounded deeper and much better balanced than that of the Vandersteen 3A Signature loudspeakers that I was reviewing at the same time. It was a pleasure to listen to the VR-2s. The three forward-firing drivers are very well matched, and the frequency response is spot on. No driver is louder or quieter than another. This is extremely rare in my experience. Often, the tweeter will be louder than the other drivers, giving a forward, bright, and aggravating sound. Another speaker may have a recessed midrange, caused by the fact that the midrange driver is too low in volume relative to the other drivers. Von Schweikert told me that he designs his drivers to his own specifications, and pays a lot of attention to making them very low in distortion. My listening tests bore this out. These speakers give you detail, but with no harshness, and again, this is very rare in today's market. The music had warmth, but none of the usual slow, lumpy, syrupy colorations. I could listen to these speakers for days on end. They sound very smooth, and the 24dB-per-octave acoustic filters help to keep the bass out of the higher frequencies. The VR-2s are not tweaky. With so many speakers (and components) these days, you have to spend months, even years, tweaking to make them sound musically satisfying. The VR-2s are the complete opposite of this. It is difficult—next to impossible—to get bad sound out of them. Changes in components and cables are very noticeable, so the definition and articulation are there, but most of the components and cables that I tried sounded great with the VR-2s. The VR-2s are extremely easy to place. You can put them pretty much anywhere and still get good sound. Once they are optimally positioned, you can control the upper midrange and high frequencies by changing the volume of the ambience tweeters. In my room, the best, most realistic results were gained by setting the control fairly low, at the number 2 marking. The VR-2s' bass response is very tight and tuneful, and while the very deepest bass is slightly woolly and loose, it is enjoyable nonetheless. It is better to hear an abundance of bass than an absence of it. I wondered if fully loading the cavity with lead shot would have improved this, but I did not attempt it. The VR-2s can play quite loud without distorting. Even at high volume, the sound was not compressed, congested, or distorted. These speakers can reproduce music ranging from orchestral to folk to rock—even disco—with equal mastery. Many modern speakers are transparent and open but leave out the warmth and the body of the music, giving a weak, anemic, lightweight sound that is ultimately fatiguing. In contrast, the VR-2s have great mid-bass, which gives warmth, drive, and body to the music, and is extremely pleasurable. Was there anything about the VR-2s that I did not like? They lacked that very last ounce of articulation and nuance. Having this would have been nice, but in all honesty, I hardly missed it. The speakers' only minor—and I do mean minor—problem is that the transition between the midrange/woofer and the tweeter is not seamless. I'm not sure if this is due to a lack of frequency extension on the part of the midrange/woofer driver or if there is discontinuous phase between the two drivers. Although the effect is audible, it is not objectionable. I found that I could reduce its significance by turning up the level of the rear tweeter, and by experimenting with interconnects and speaker cables. Also, some types of music made the problem more noticeable than others. I don't want to make a big case of this, but it is my job to be critical. The problem was only noticeable because these speakers are just so darn good. The Von Schweikert VR-2s are a musical bargain. Considering their price, the fit and finish of the cabinetry is excellent. They are very well made, and very well engineered. They produce holographic images and a focused, realistic, large, and deep soundstage. The drivers are very well balanced, and the speakers are very easy to listen to for extended periods of time. The depth and quality of their bass is outstanding. These speakers can play all types of music with aplomb. It was a delight to listen to the VR-2s. They brought great pleasure to every kind of music. George Pappas Specifications
Von Schweikert Audio
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