Electrovoice 205-4t Manuel D’Utilisation

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EVID Design and Installation Manual 
 
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6
 
What general guidelines do I consider when deciding on the 
physical placement of the EVID 12.1 subwoofer? 
It is often desirable to place the subwoofer in the middle of the room to get the most 
uniform coverage. Even though a subwoofer projects sound omni directionally and that 
the sound is generally not localizable, there is still a reduction in subwoofer sound level 
the farther away one gets from the subwoofers installed location.  Placement in the 
middle of a room however lowers the sensitivity and ultimate maximum SPL of the 
subwoofer. You can also use additional subwoofers in order to attain more even 
coverage.  To get good SPL levels, it might be necessary in some applications to install 
the 12.1 subwoofer along a wall or in a corner.  
What typical subwoofer/satellite system configurations are 
possible? 
The EVID Series contains a variety of models, allowing great flexibility to configure a 
system to fit the requirements of many different applications. Some typical examples are 
illustrated at the end of this guide 
How large an area can an EVID system cover? 
A system consisting of one 12.1 subwoofer and four 4.2 or 6.2 satellites can cover up to a 
4000 square foot room with balanced, even coverage. The estimate of 4000 square feet is 
a typical coverage area.  You can scale the coverage up or down to adjust for applications 
with different SPL requirements and different size rooms. 
What are general wiring/electrical guidelines when assembling 
complete EVID systems with a subwoofer? 
Because the 12.1’s crossover network does a good job of separating the low-pass and 
high-pass frequency bands you can usually consider the impedance in each band as being 
nearly separate from each other.  The crossover frequency is set for the ideal 160 Hz 
acoustic crossover point with a 4-ohm load on each satellite output. It is best to use a 4-
ohm load on each satellite output when possible. Increasing the impedance of the 
satellites on a satellite outputs lowers the crossover frequency to the satellites, resulting in 
more overlap between the subwoofer and the satellite. Using an 8-ohm load on each 
satellite output results in operating the satellite down to 80 Hz. With the subwoofer 
operating up to 160 Hz, this could result in a frequency response bump between 80 Hz 
and 160 Hz, where both subs and satellites are operating. This is a situation to be aware 
of when placing the speakers in the room. 
What is the best way to connect the EVID 12.1 for single channel 
operation? 
To operate a 12.1 subwoofer in mono, parallel the two subwoofer inputs, resulting in a 
4Ω load in the subwoofer range, below 160 Hz. When hooking an EVID 12.1 in mono IT 
IS VERY IMPORTANT TO MAKE SURE THAT BOTH INPUTS ARE CONNECTED 
IN PROPER POLARITY.