User's Manual

CL865-DUAL Hardware User Guide
1vv0301104 Rev.1 – 2014-03-07
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Reserved. Page 46 of 70
Mod. 0805 2011-07 Rev.2
10.1.2. EAR Connection
The audio output of the CL865 is balanced, this is helpful to double the level and to reject
common mode (click and pop are common mode and therefore rejected). These outputs can
drive directly a small loudspeaker with electrical impedance not lower than 32Ohm.
TIP: in order to get the maximum audio level at a given output voltage level (dBspl/Vrms),
the following breaking through procedure can be used. Have the loudspeaker as close as you
can to the listener (this simplify also the echo cancelling); choose the loudspeaker with the
higher sensitivity (dBspl per W); choose loudspeakers with the impedance close to the limit
in order to feed more power inside the transducer (it increases the W/Vrms ratio). If this were
not enough, an external amplifier should be used.