General Operation; Audio Connections; Ac Power Connections - JBL LSR25P Owner's Manual

Section 3: General Operation
3.0 Introduction:
The LSR25P Bi-amplified reference monitor sets a new standard for exceptional
performance in a compact near field design. Using a combination of advanced transducer
engineering and powerful drive electronics, the LSR25P will stand up to the most demand-
ing sessions.
The 5.25" woofer is based on JBL's Symetrical Field Geometry (SFG)
With a massive 1.5" drive coil, excursion capability is maximized while retaining excellent
distortion performance. The heavy magnetic structure keeps power compression to a mini-
mum to reduce spectral shift as power levels increase. The tempered paper cone forms a
rigid piston and is supported by a soft butyl rubber surround. The entire driver is shielded
for use near video monitors and other equipment sensitive to magnetic fields.
The high frequency device is a 1" composite diaphragm integrated with an
Elliptical Oblate Spheroidal (EOS) Waveguide with 100 x 60 degree dispersion which is
critical to the smooth spatial response required in today's working environments. The
design, as with the woofer above, is shielded.

3.1 Audio Connections:

The LSR25P comes with an XLR and RCA connectors to accommodate a wide
range of signal levels and balanced or unbalanced configurations. The XLR input is nomi-
nal +4 dBu sensitivity and the RCA input is -10 dBV. Variable user calibration can also be
accommodated using the front mounted volume control. Positive voltage to Pin 2 of the
XLR or the pin of the RCA jack will produce a forward motion in the low frequency cone.

3.2 AC Power Connections:

The LSR25P has power transformers which allow them to be used with multiple
AC supply voltages around the world. Before connecting the unit to AC power, confirm that
the switch setting on the rear of the unit is set to the proper position and the fuse is the cor-
rect rating. The LSR25P will accept voltages from 100-120 or 200-240 Volts, 50-60 Hz when
the voltage setting and fuse is correct. The ground terminal of the IEC plug is required by
wiring codes and regulations. It must always be connected to the electrical installation
safety ground. The LSR units have carefully designed internal grounding and balanced
inputs and outputs to reduce the possibility of ground loops (hum). If hum occurs, see
Appendix A for suggested audio signal wiring and system grounding.
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