Electrovoice 205-4t Manuel D’Utilisation

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EVID Design and Installation Manual 
 
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9
 
infrastructure of the audio system is a constant voltage design you would employ the “t” 
versions. 
Do the EVID “t” models work with both 70v and 100v systems? 
Yes, the same “t” models work on both 100v and 70.7v lines. Regardless whether you use 
100v or 70.7v distributed line systems; you use the same model speaker.  
What are the power taps for the various EVID “t” models”? 
•  3.2t: A single (non-selectable) power tap rated at 5w@70v and 10w@100v. 
•  4.2t: The power taps are 30w, 15w and 7.5w at both 70.7v and 100v, with a 3.7w 
tap for 70.7v only. 
•  6.2t: The power taps are 60w, 30w and 15w at both 70.7v and 100v, with a 7.5w 
tap for 70.7v only. 
A rotary switch on the back panel selects the taps for the 4.2t and 6.2t. A label is 
provided on the back of each speaker showing the switch positions to use for the settings 
at 70v and 100v. 
Can I run a 12.1 subwoofer on a 70v or 100v distributed line?  
To operate the 12.1 on a distributed-sound line, you need to add a matching transformer, 
which must be a high quality transformer such as the ElectroVoice 15000 series. Many 
other transformers saturate at low frequencies, dropping the impedance in the subwoofer 
range to a fraction of what it is at higher frequencies. This can draw too much current 
from the amplifier either causing the amp to fail or creating distortion such as premature 
amp clipping or “muddy sound” at low levels. This can adversely affect the sound that 
goes through the full-range speakers as well 
The more power you put through the transformer the more it can saturate, so even a 
transformer that performs well on low-signal test equipment can saturate severely on 
higher voltage distributed lines. It requires a high performance transformer to drive a 
subwoofer successfully on a distributed line.  All the EV 15000 series transformers are 
designed to perform to spec. up to their rated power. 
In the long run, it is better to run a subwoofer from its own low impedance amplifier 
channel and run only the satellites from the constant voltage (70v/100v) line. 
What equalization should I use for EVID systems? 
The proper equalization settings depend on many factors, such as the quantity of 
speakers, the room characteristics, the typical operating level, the residual background 
noise in the venue, and the type of audience.  The wide frequency response and high 
power handling of EVID systems lets you use a wide variety of equalization settings.