High-quality VS 240 bookshelf loudspeakers offer a combination of size and performance that many buyers—including critical listeners—consider ideal, both for stand-alone music systems and multi-channel setups. The VS 240 system adds physical beauty and an element of choice to the bookshelf equation. Compact enough to sit comfortably on virtually any shelf or tabletop, yet powerful enough to fill all the but largest rooms with robust, richly-detailed sound, each VS 240 features an advanced OCCM full-range transducer for tighter bass response, and an SWB tweeter for louder, more realistic high-frequency sound at any listening level. While both systems deliver exceptional bass, pairing either with the VPS 210 powered subwoofer, which can be easily integrated into most spaces, takes bookshelf performance to a level all but indistinguishable from that of a floorstanding system.
2-Way 4-1/2 " High Performance Bookshelf Speaker.
- 4-1/2" (114mm) OCCM woofer
- 1" (25mm) SWB tweeter
- Elegant black lacquer piano finish cabinet
- High-gloss furniture-grade end panels
- MagnaGuard video shielding
- Gold-plated 5-way binding posts
Boston's Super Wide Bandwidth (SWB) High -Frequency Transducer Tweeter
This extraordinary new tweeter incorporates an array of features and technologies that result in great transparency and micro dynamics with a low frequency extension that ensures a full-bodied sound character at high output levels.
The SWB's Coupled Dual Concentric Diaphragm (CDCD)
The advantage of using the new Boston Acoustics CDCD diaphragm is that its center is terminated to a brass plug that extends from the motor system. At high frequencies (i.e. above 10-12 kHz) the center of a traditional dome shaped diaphragm is gradually decoupled and begins to move out of phase with the remaining diaphragm structure causing cancellation of higher frequencies and a loss of radiating surface area. Terminating the center portion prevents this from happening and forces the diaphragm to operate in a “bending wave” mode, which has significantly lower distortion and no phase cancellations. In this way, the CDCD works more like a piston—and this lowers the ”noise floor”. The larger surround ensures sufficient
high frequency radiation and improves dispersion. It also compensates for the loss of center diaphragm area
and lowers compliance. The layering of materials is used to make a composite sandwich.
Organic Composite Cone Material (OCCM)
When selecting a high performance loudspeaker cone material for VS Series, the engineering team at Boston Acoustics required the material’s performance qualities to meet our highest standards. In order to acheive maximum performance, the VS Series loudspeaker cone material needed to exhibit 3 principal qualities:
Lightweight - To achieve faster speed allowing for greater attack transient response while maintaining good sensitivity
Rigid - To remain pistonic and minimize cone break-up even during higher output
Highly-damped - To minimize resonances and provide un-colored accurate motion throughout it’s specified band
The Organic Composite Cone Material or OCCM chosen for VS is a new lightweight, strong, and well-damped cone material developed to have superior sound characteristics. Through the use of select natural fibers making the material less uniform, it virtually eliminates the inherent cone break up modes exhibited by many other common cone materials, and provides VS with a cone platform for inherently accurate motion and sound.
While OCCM cones are very light they are also very rigid because the random crossing natural fibers strengthen the paper base material much like carbon fiber, but at a lower weight. By using OCCM along with premium transducer components, such as aluminum cast baskets and rubber surrounds, VS Series loudspeakers are able to achieve increased output, improved accuracy, and a high level of reliabilty.
Cabinet Construction
The speaker enclosure plays a vital role in the sound reproduction chain. It provides a foundation for the woofers to generate of high-level bass while remaining neutral in acoustic color and adding none of its own character. The enclosure should not flex or resonate and it should not allow standing wave buildup which
could influence the behavior of the speaker units. The enclosure should also be strong and stable, offering rock solid anchoring for the higher frequency drivers so an accurate acoustic image can result.
Most cabinets are made of man-made wood, which is inexpensive, relatively strong, well damped, and easily machined and finished. It’s well known in the aviation industry, that composite materials can benefit from their constituent components in a way that exceeds the performance of each of them separately. Typically, composite materials exhibit a much higher strength than any of the component materials, and they can benefit from enhanced damping characteristics as the layers work against each other. For this reason, we chose to make our VS Series loudspeaker cabinets from several layers of dissimilar wood materials, sandwiched together in a high pressure curved set of tools and cured with high frequency RF energy. The result is a stable curved composite wood board material that can be further machined and assembled into a loudspeaker enclosure.