Bosch EVF-1122S/126 EVF-1122S/126-PIB User Manual

Electro-Voice EVF/EVH User Manual

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For full-range systems in the passive mode, the internal crossover/equalizer network sends low frequen-

cies to the woofer and high frequencies to the compression-driver/waveguide combination. In addition, 

the network tailors the frequency response and levels of each individual driver so that the overall frequen-

cy response of the loudspeaker is essentially flat over its design operating range.

Once a cluster of EVF and/or EVH systems is installed in a venue, a digital signal processor (DSP) will 

typically be used to adjust the in-room frequency response, based on the specifics of the situation. In 

addition, the DSP should be used to provide the high-pass filters recommended to protect EVF and EVH 

systems against overdrive at frequencies below their operating range. Failure to do so could damage the 

low-frequency drivers if fed high-level signals below the system’s operating range. Table 3 shows the 

recommend high-pass filter frequencies for infrasonic protection of EVF and EVH systems.  Different high-

pass filter frequencies are recommended for some fiberglass versions based on changes in operation 

range due to the effects of having a sealed enclosure.

EVF-1122/XX

65 Hz

EVF-1152/XX

45 Hz (55 Hz for Fiberglass Versions)

EVF-1121S

50 Hz (55 Hz for Fiberglass Versions)

EVF-1151S

35 Hz (45 Hz for Fiberglass Versions)

EVF-1181S

33 Hz

EVF-2121S

45 Hz

EVF-2151D

35 Hz

EVH-1152/XX

60 Hz