User manual ALPINE SPX-Z18M

[. . . ] Read this manual carefully before starting operation and use this system safely. We cannot be responsible for problems resulting from failure to observe the instructions in this manual. This manual uses various pictorial displays to show how to use this product safely and to avoid harm to yourself and others and damage to your property. When drilling holes in the chassis for installation, take precautions so as not to contact, damage or obstruct pipes, fuel lines, tanks or electrical wiring. [. . . ] Achieving the most phase coherent and flat summation possible requires controlling the amount of inherent phase shift of each filter, and is directly related to the selection of filter order, Q and cut-off frequency. Again, this relationship is also affected by the distance and angle of each driver relative to the listener and their proximity to each other. Since the acoustic center of the midrange will be farther back than the tweeter in nearly all applications, minimal delay is desirable in the midrange low-pass. Subsequently, this filter is of low order, and leaves much of the adjustment capability for the mid/tweeter transition to the tweeter high-pass section. For the midrange high-pass, higher order configurations are used in most applications to achieve phase linkage with the woofer (see WF-LP section). for general reference , the available midrange network configurations are listed below. In certain installations where positioning or placement necessitates level adjustment, a jumper is provided that boosts midrange output by approximately +2dB. As an additional note, either filter (high-pass or low-pass) may be bypassed independently for semi-active applications. Since it is often difficult to position the woofer and midrange close together or at equal distances, it is critical to achieve phase linkage between them to avoid localization, image smear, poor staging, etc. Additionally, vehicle interior dimensions are typically close to the wavelength of the woofer/midrange crossover region, so it may be necessary to minimize overlap to reduce the chance of generating a complex canceling sound field or response aberrations. Therefore, a variety of higher order filter types and characteristics are provided in this section, making it possible to link the two drivers in relative phase for a smooth transition in many applications. Again, it is important to note that the selections made in both the WF-LP and MID-HP sections produce a net effect, and must be set in such a way so as to work together. SIGNAL LINK: The signal link jumpers provide a parallel connection between the input sides of the terminal blocks, eliminating the need for extra terminals or wiring when using a single or dual input. Caution: These jumpers must be removed accordingly when used in a bi-amp or tri-amp configuration to prevent possible damage to amplifiers. System Description With all three drivers mounted close together and equidistant to the listening position, this is surely the most favorable configuration for a component speaker system. Although such an installation may not often be practical in situations other than the demoboard, it is certainly possible given the custom fabrication techniques available today. In anticipation this, a degree of tolerance is built into the settings described below for the most likely cases, though some experimentation may be necessary if all conditions cannot be met. If choosing to go beyond the recommended settings or utilizing the network in a partially active mode, keep in mind that phase coherence and flat summation remains critical even in the idyllic flat baffle situation, as each driver type exhibits unique phase and group delay characteristics. Type-1B is for such cases where pathlength is nearly the same to all drivers, but where the mounting surface orientation creates a uniform but fairly extreme off-axis listening angle. Network Jumper Setting Type-1A: Pathlength to the listening position is considered to be basically equal in this case (ideally 2-3m away), with relative on-axis positioning of all drivers. Phase linkage is accomplished with a low Q 2nd Order high-pass filter on the tweeter, 1st Order lowpass and 4 th Order high-pass on the midrange, and a semi-4th Order low-pass on the woofer. Again, please note that the tuning of the settings below considers the best balance between driver and passenger listening positions, so all distances and angles are referenced to the nearest side. [. . . ] In order to minimize overlap while maintaining phase coherence between the mid and woofer, a 3rd order high-pass and semi-2nd order low-pass are applied, resulting in a summation point of 600Hz. Since the tweeter and midrange are farther away, minimal delay and some level adjustment are desirable, utilizing a low Q semi-2nd order high-pass on the tweeter and a 1st order low-pass on the mid for a resultant acoustic crossover point of 3. Highlighted tweeter level jumpers are the recommended settings for each configuration, but user adjustment may be desirable. Transfer function simulations only illustrate the effect of the filter upon the input signal, and therefore do not represent the actual frequency response of the system. [. . . ]