Low-frequency Enhancement MethodsA number of methods are used to enhance low frequency response in speaker enclosures. In bass reflex designs, a tuned port in the enclosure boosts low frequencies emanating from the rear of the speaker unit. The VXS10S adopts this method, specializing in more powerful low frequency reproduction. The problem with this approach is that as the enclosure becomes smaller or thinner, the size of the port must be reduced accordingly, resulting in increased resistance and correspondingly reduced bass enhancement. Bass reflex designs are not always suitable for compact enclosures.Passive radiator designs avoid the use of a port, instead boosting bass response with a tuned passive “drone cone.” The passive radiator method is more suitable for compact enclosures, but the passive cone tends to be heavy, requiring some form of firm, durable suspension that can reduce efficiency. The directivity of the passive radiator also places restrictions on where and how the system can be installed.Original Yamaha SR-Bass technology employed in the VXS3S suspends a four-sided diaphragm on only one of its sides, using the resonance of the diaphragm to enhance the system’s low-frequency output. There are no limitations on the shape and materials used for the diaphragm, making SR-Bass technology applicable to a wide range of speaker designs, including compact models.Yamaha offers 2 choices. That is compact VXS3S and powerful VXS10S. Please select the best model for your application.