Actual Max SPL, Speaker Type for 70V/100V Systems

Sub-Sat Design Considerations

Sound Level Capability

For each system in this guide, the Max SPL figure is listed, describing the continuous sound level that the system can maintain on a full-range basis with either speech or music program content, with 10 dB headroom for clear transient peaks.

For any installation, the satellite speakers might be located next to each other and cover exactly the same area, resulting in 6 dB of coupling between them, or they might be located far apart and have no overlap between then resulting in no coupling. The Max SPL figures listed in the charts assume somewhere in between, that there is some degree of overlap in coverage but not full overlap. Therefore, a coupling figure

of 3 dB is utilized.

Actual Max SPL

For applications where there is very little overlap of satellite speakers, the actual Maximum SPL will be 3 dB lower for 2 satellite speakers (and 6 dB lower for 4 satellite speaker) than what is listed. For applications where there is almost full overlap (satellite speakers covering the same area), the actual Maximum SPL will be 3 dB higher for 2 satellite speakers (and 6 dB higher for 4 satellite speakers).

Subwoofer Location’s Affect on Sensitivity and Maximum SPL

The system performance figures listed are based on the subwoofer being located away from boundary junctions and corners. For applications where the subwoofer will be placed at a 2-surface boundary junction (wall/floor, wall/ ceiling, wall/wall), both the Sensitivity and the Maximum SPL of the subwoofer increases by 6 dB. For applications where the subwoofer is placed as a corner junction (wall/ wall/ceiling or wall/wall/floor), the Sensitivity and the Maximum SPL of the subwoofer increases by 12 dB.

This can unbalance the subwoofer satellite sensitivity balance. It is a good idea to have an equalizer in the sound system to be able to adjust the bass level for proper balance. A parametric EQ allows for the best adjustment. For graphic EQ, a minimum of 15 bands is usually required to be able to set the EQ break point at the proper frequency.

Using the MTC-210-SAT Input Module

ALL these systems (except the CCS6000 System that utilizes a SB-2 subwoofer) utilize the MTC-210-SAT input module installed in the back of the Control SB-210 subwoofer.

This module provides a full passive crossover consisting of a high-pass to the satellite speakers and low-pass to the subwoofer drivers.

4 Ohm / 8 Ohm Setting

(ie, Satellite Speaker Impedance Selector)

The module contains a header adjustment for setting the crossover to work properly with either 4 ohm or 8 ohm satellite loads per

output.

Mono / Stereo Setting

The module also contains a header to set the system to operate either as a mono system with a single input (+ and -) wired to the Left/Mono input terminals, or as a full stereo system with Left input wired to Left input terminals and right input wired to

Right input terminals.

Figure 1

Setting Mono/Stereo and Satellite Impedance Headers

on MTC-210-SAT (and MTC-210T-SAT) Input Module

Mono/Stereo and 4/8 Ohm selection is accomplished by moving the headers on the MTC-210-SAT Input Module before installing the module into the subwoofer. Yellow indicators move with the headers, annunciating the selected modes visibly on the back panel of the subwoofer after the module is installed. Header positions shown in the picture above are set to Mono with 4 ohms per channel of satellite speakers. Moving the headers in the position of the red arrows changes the settings to Stereo with 8

ohms per channel of satellite speakers.

Operation from a 70V/100V Distributed Speaker Line

A different SB-210 input module needs to be purchased for operating a subwoofer satellite system via 70V/100V. It is model MTC-210T-SAT, which includes input 70V/100V transformers as well as the built-in crossover network.

Speaker Type for 70V/100V Systems

Satellite speakers remain LOW-IMPEDANCE (non-T) models. DO NOT use T-version satellite speakers for any of the satellite speakers, even those systems operated from a

70V/100V distributed speaker line.