Von Schweikert Audio

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					Von Schweikert Audio
World-Class Reference-Grade Speakers for Music and Movies



Quick-Guide Setup Instructions Including:  Interactive Room Correction  Equalization Settings  Technical Setup Info

Von Schweikert Audio
930 Armorlite Drive, San Marcos, CA 92069 Ph 760-410-1650 Fx 760-410-1655

TABLE OF CONTENTS      

Initial Room Placement Interactive Room Correction Equalization Settings for Room Correction Woofer Equalization Midrange/Tweeter Equalization Ambience Retrieval Setting

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Initial Room Placement
 Engineering Background The VR-9 SE was designed to work with the room to provide a life-like threedimensional recreation of the original live musical event. It is well appreciated by listeners as well as musicians that musical instruments radiate sound omnidirectionally by nature of their construction. In addition, the best microphones are designed to pick up sound over a “wide dispersion pattern” in order to simulate the original sound-field. For this reason, the VR series of speakers are “wide dispersion” designs based on the study of Psychoacoustics. Since a “wide dispersion” design uses the room acoustics to enhance the listening experience, great care must be used in setting up the VR-9 SE speakers if the best possible sound quality it to be achieved. The following information will help you extract the magic that these speakers are known for. 1. In all rooms, no matter what the size or reverberation time, the setup needs to emphasize the 3-D imaging focus of the speakers; don’t worry about the balance between bass and treble, as the frequency response of the VR-9 SE can be equalized with the on-board controls to enable the speakers to sound natural (and also have flat measurement response). 2. If your room is rectangular, and you have placed the speakers on the “long” wall, you can spread the VR-9 SE by 15 feet before a “hole in the middle” will develop. If you have spread the speakers further apart than the listening distance, the image focus will be best if the speakers are aimed directly at the listener’s ears. Aiming them at you is called “toe in.” If a wider and/or 2

mellower sound is desired, try reducing the angle of “toe in;” in some rooms you may find that the speakers sound best with no “toe in,” so experimentation is in order. If you are using a wide spread, the sound will be more dimensional and holographic if the speakers are kept as far away from the walls as is possible. If necessary, use diffusion at the first reflection points, including side walls and ceiling. If you have a hardwood floor, or large coffee table, note that reflections from these hard surfaces will increase the upper midrange/treble range to an unacceptable level. In this case, you will need to use a large throw rug in front of each speaker and break up the reflections from the top of the coffee table with objects placed on the table to diffuse the sound rays from the speakers. 3. In a long and narrow room, if you are placing the speakers on the “short” wall and are sitting at the other end of a reverberant room, you will notice that the room’s natural reverberation caused by boundary reflections (walls, floor and ceiling) will dominate the sound. In this situation, you may wish to sit closer and/or use room treatment to absorb the excess reverb. Scientists working in acoustics have found that highly reflective rooms with excess reverberation will contribute about 60% - 70% of the total sound field. This means that without some type of room treatment, the rooms’ colorations will dominate the overall sound; the majority of rooms may have so much reverberation that the speakers cannot focus a three-dimensional image of the instruments floating in space. Sometimes, the speakers themselves may be incorrectly blamed for the poor resulting sound field. If this is the case with your particular room, the two options are a): sit closer to the speakers or b): use adequate room treatment.

 Engineering Background One of the most important aspects of sound reproduction is to match the original recording’s frequency balance as recorded in the original venue. Since the average listening room does not have the same acoustical signature as the original concert hall or sound studio where the music was recorded, it is very likely that the listening room’s signature may have a negative impact on the resulting sound from the speakers. Indeed, the frequency response of the room may cause bass lift (often called “boom”) and/or excessive treble reflections that may cause a “bright” (harsh) sound. Both of these room aberrations will cause listening fatigue and/or boredom to set in quickly. This is the major reason why certain audiophiles change speakers every few months: they are, looking for that elusive “magic” sound that the room is destroying. In most rooms, the only practical solution is to enable the speaker to compensate for non-flat frequency and/or phase response caused by the room conditions.


Although “all” frequency ranges are affected by room reflections, there are two main regions that are most bothersome to the listener and are amenable to adjustment with simple equalization controls. The two most important ranges are: a. Deep bass to mid-bass (16Hz to 80Hz); b. Upper midrange to low treble (1kHz to 4khz). Both of these frequency ranges are amenable to correction if access to electrical equalization is enabled. In the case of the VR-9 SE, the correction has been designed into the speaker system itself:  The bass range of the woofer system is actively controlled by the built-in 1,000-watt ICE-BLOK amplifier module, see the next section regarding the controls and how to set them up for your particular room and/or listening taste. (Although the built-in amplifier drives only the 15” High-Speed rear-mounted subwoofer, the entire bass range up to 120Hz can be altered by the subwoofer’s interaction with the main woofers.)  The upper midrange-tweeter frequency range (1kHz upwards) can be attenuated or boosted with the rotary knobs that control the passive Autoformer devices, which are simply transformer input/outputs with 1dB selector switch points. The Main tweeter (Scanspeak Dual-Ring Radiator) can be controlled upwards of 1.5kHz; this is the ear’s most sensitive range and covers the upper midrange region of female voices, violins, pianos, guitars, and other instruments. * Note that the VR-9 SE’s frequency correction does not come at the expense of “purity” of the signal; these controls cannot negatively affect the overall sound unless they are misadjusted. The following technique can be used to easily adjust the system bass and treble response using the supplied Pink Noise CD:


Please refer to the built-in ICE-BLOK amplifier control plate, mounted on the rear of the VR-9 SE woofer enclosure. There are two rotary controls marked with numbers and three toggle switches below them. Note: all of the Default Factory Settings for Flat Frequency Response in a typical listening room are marked with gold dots. Starting from the top of the subwoofer amplifier control plate, you will see: Level Control Adjusts the volume level of the ICE-BLOK subwoofer amplifier driving the 15” subwoofer. This knob has a default setting marked by the gold dot on the amplifier plate (approx. at 12:00 o’clock position). IF the deep bass sounds too loud in your


room, turn down the control slowly on both speakers, if they are arranged symmetrically with equal distances to the side walls. In the event that one of the speakers is close to a room corner and the other speaker is out in the open, the speaker loaded by the corner will require much less bass boost than the speaker in the open area. In this case, do not worry about using less bass LEVEL in the corner speaker. In one particular room, the setting for “flat’ response turned out to be at the 10:00 o’clock position, but in a different room (that seemed to be lacking in bass with other brands of speakers), the setting for “flat” turned out to be at about 1:00 o’clock. Do not be alarmed if you find yourself adjusting this control to compensate for recordings that have too much or too little bass in the mix, as there is no “standard” for bass level; it is set by the recording engineer’s tastes. Low Pass Control This knob adjusts the crossover point between the 15” rear-firing subwoofer and the twin- 9” front-firing midbass woofers. Note that the main 9” woofers are flat down to 40Hz in their sealed configuration, so the job of the 15” subwoofer is to fill in between 10Hz and 40Hz. Based on your particular room situation and/or listening tastes, you may wish to overlap the crossover area between 40Hz and 80Hz in order to reproduce very powerful orchestral or jazz recordings that should be “flapping your pant legs” in real life, but sound weak in a typical room. Note that too much midbass generated by the 15” woofer may overload a very small room – in this case, reduce the midbass overlap by turning the Low Pass knob to the left. 25-Hz Bass Boost toggle switch In many rooms, the extremely deep bass (10Hz to 40Hz) may be “missing in action” due to the standing waves set up by the boundaries created by the floor, ceiling, and walls. In our particular room, we use the 25Hz Bass Boost to increase the deep bass power, so the Factory Default Setting is marked by the gold dot on the right side of the toggle switch. In the event that you are hearing too much deep bass, turn off the 25Hz Boost. Phase toggle switch This switch could also be labeled Monopole/Dipole setting, since the polarity of the 15” woofer can be used to either strengthen the 10Hz to 80Hz region by setting the Phase switch to 0-Degrees, which is the Factory Default Setting marked by the gold dot. In the event that the midbass (or entire bass range) is too overpowering for the room, set the Phase switch to the other side, which is marked 180-Degrees. This setting will result in a Dipole woofer arrangement that focuses the bass power in a forward direction, which may reduce the effects of “one note bass” generated by room nodes. The best way to determine how to set this switch is to start with the 0Degree setting and listening to a variety of recordings. If you feel that the bass is too loud compared to the midrange, it will be very useful to use the 180-Degree “out of phase” position.


Auto Off toggle switch Since it is not convenient to turn of the subwoofer amplifier by using the On-Off switch at the rear of the speaker, the Auto Off switch will turn off the ICE-BLOK amplifier after no sound is detected within a 15-minute period. The Factory Default Position is marked with a gold dot. This control has no effect on the sound quality and is just a convenience feature.

If bad recordings and/or boomy or bright listening rooms didn’t exist, our hobby would be far more pleasant, wouldn’t it? We could actually sit down and enjoy the music instead of worrying about “bad sound” every time we turn on our stereos! It is well known that a speaker that is designed to be as accurate as possible will often sound unpleasant – this is not due to the speaker itself, but the fact that the speaker system is letting you hear EVERYTHING, both good and bad. Can we do something about this? We’ve all experienced “boomy” or “bright” rooms, components, and recordings I decided that a really accurate speaker should be able to compensate for these unwanted artifacts. In fact, many of the recordings I own from the past 50 years either have too much bass or treble, or even worse, have harshness in the upper midrange due to the “bright” nature of the recording studio electronics and miles of inexpensive cables. (This doesn’t even count the engineers who love boosting the treble with equalization due to their loss of hearing caused by excessive volume.) For these reasons, I have developed a method of enabling the speaker to be accurate and also sound musical. This was accomplished by two methods: A. Reducing the distortion and coloration created by the speaker system; B. Designing basic equalization controls that will NOT interfere with the transparency of the basic sound. Since most of the harshness of older recordings is caused by upper midrange distortion and/or boosting of these frequencies by the recording engineers, this type of unpleasant frequency imbalance can be corrected by lowering the volume level of the offending frequencies themselves. Our study of the spectral imbalances in recordings and/or listening rooms occurs at two general areas:  Upper midrange (1kHz to 4kHz)  Treble range (4kHz to 10kHz). Cool, now that we know what frequencies we need to adjust, how do we go about doing it without causing additional sonic nasties? My answer was to design “autoformers” that could attenuate (reduce) the offending frequencies; (autoformers are low distortion volume controls based on transformers). Yes, they are hand made in Japan and are frightfully expensive, but the VR-9SE was designed to be the best speaker in the world, after all.


LOCATION OF THE ATTENUATORS AND THEIR SETTINGS: Note: all of the Default Factory Settings for Flat Frequency Response in a typical listening room are marked with gold dots—the controls have markings that have been factory preset to these gold dots. Looking at the rear of the VR-9SE’s upper midrange/tweeter module, you will see a control plate on either side of the RIBBON Rear-Firing Ambience Retrieval Driver: HIGH TREBLE ATTENUATION (10kHz - 100kHz) On the left side of the upper speaker, you will see that the black plastic control plate has two different knobs, a large knob with a “pointer groove” at the top of the plate and a smaller knob below it. The large black knob controls the volume level of the 5” ribbon super tweeter on the front of the cabinet and operates between 10kHz to 100kHz (the very upper treble range – note that these frequencies are so high that it is difficult to actually hear them unless you listen carefully to the ribbon tweeter with the volume level off, then on. A long-term comparison will prove to you that the subtle addition of extra “air” in the frequency response up to 100kHz enables the VR9SE to have far more clarity and transparency than speakers that don’t go up as high in frequency.  Note that the gold dot painted on the number plate indicates Factorymeasured Flat Response, and that there is a “pointer groove” on the top of the large knob that is set to the gold dot. (The actual numerical marking is labeled “16/17” and the selector switch at the bottom of the knob is set to the “0-dB” setting). If your room tends to sound “dull” and you own equipment that needs more “air” at the high frequencies, please turn the control knob clock-wise until you hear what you are seeking. If you hear aggressive high frequencies, you should first try turning down the Main Tweeter with the large control knob on the right side, see below. In our experience, the ribbon supertweeter does not operate in the “harshness” area.

 

LOW TREBLE ATTENUATION (1 kHz – 4 kHz) Looking at the right side of the upper speaker, you will see another black plastic control plate, with a large black knob at the top and the binding posts below. This is the frequency range where most of the room reflections and/or harsh recordings can be adjusted. The round Main Tweeter on the front of the cabinet operates from 2kHz up to 40kHz, so we have set the Autoformer to attenuate the sound between 1 kHz and 4 kHz, where the ear is most sensitive to harshness and distortion.  Note: all of the Default Factory Settings for Flat Frequency Response in a typical listening room are marked with gold dots. The Factory-measured Flat Response setting is numerically marked “ 5/4” on the number plate, with a gold


dot on the right where the “pointer groove” is marked. The slide switch under the large knob is set to “0-dB” and there is a gold dot for reference as well. REAR-FIRING AMBIENCE RETRIEVAL SYSTEM CONTROL The VR-9SE has been designed to replicate the pickup pattern of a typical omnidirectional recording microphone to enhance the Three-Dimensional image focus of good recordings. To enable this effect, we have installed a rear-firing Ambience Retrieval system using a 5” ribbon to replicate a decoded reverberation signal derived from our Ambience Retrieval Decoder circuit. The Effects Level is controlled by the small knob on the left side control panel, directly below the large black knob. Note that the small knob has a white arrow, set at 12:00 o’clock (referring to a clock face, not numbers on the dial). Note the gold dot painted directly above the small knob is the Factory-measured Flat Response setting.

Theory : Since a recording mic picks up sound from a 360-degree window, reflections from the back of the recording hall or studio end up at the rear of the mic – this signal is phase reversed and is also time delayed due to the distance from the rear wall to the back of the mic. Our Ambience decoder retrieves this ambience signal and feeds it to the rear-firing ribbon speaker, thus completing the original 360-degree sound-field. If you have placed the VR-9SE close to the rear wall, you may have to lower the volume level of the Ambience Driver if the effect is boosted by the rear wall. Turn the small knob to the left to reduce the Ambience Effect. If you have the VR-9SE out into the room and you wish to have more depth to the sound, then turn up the small knob clock-wise. Our factory sound room is somewhat overdamped, so we use the Ambience Effects level set to 100% full volume.

Please take the time to play with all of these controls to learn what they can do for your sound. If you have read the detailed review of the VR-9SE at our website, you will find that Mike Levine, the owner/customer/reviewer, spent about a year playing with all of the controls on his personal pair of VR-9SE’s. Not only did Mr. Levine have a lot of fun, but his friends were also helpful in offering suggestions for the control settings when different components were switched in and out of the system. Note that the VR-9SE is considered to be the most accurate speakers ever built, and if you are having any issues with their sound or adjustments, please call the factory for detailed help in setting the controls. Albert Von Schweikert will be pleased to speak with you and has had 100% success rate with each and every VR-9SE customer. Happy Listening!


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