Xantech PA1235X Stereo Amplifier User Manual


 
Model PA1235X Page 9
© 2002 Xantech Corporation.
6. As a rule of thumb, use 18 gauge speaker wire for speaker runs up to 30' (9m), 16 gauge up to 70' (21m), and
14 gauge up to 150' (39m). The 4-terminal connectors accept wire sizes up to 12-gauge max.
7. Strip the insulation back about 1/4" (6mm) and twist the strands on each lead to prevent fraying.
CAUTION: After lead ends are inserted and the screws tightened down, be sure there are no free strands
that could cause shorting!
Speaker Phasing
To obtain stable imaging and full bass response, it is imperative that stereo speakers be connected "in phase"
with each other. You can verify this as follows:
a) If the "+" (positive) and "–" (negative) terminals on your speakers are correctly marked, and visible, and you
have wired the system as shown in Figs. 5 and 7, then the system will be "in phase". No further action is
required. Most manufacturers identify the positive terminal with a red binding post, a "+" sign, or a red dot.
b) If you are unsure of the markings, you can verify the phasing. Using a mono sound source, such as AM radio,
alternately reverse the leads to one of the speakers. Pick the connection that delivers a solid center image
between the speakers as well as best bass response.
Bridged Mode Connections
In general, it is recommended that the BRIDGED mode not be used
in multi-room applications where
several speakers are driven through room volume controls and the like. For such applications, use the
STEREO mode. Use the BRIDGED mode for single speaker, higher power applications, such as in surround
sound systems. Use speakers with an impedance rating of 8-Ohms minimum.
To make connections for the BRIDGED mode, follow the steps given before for stereo connections, but with the
following differences:
1. You may connect the RCA-type patch cables from the OUTPUT jacks of the driving preamp or other source
to either the LEFT or the RIGHT input jacks of the bridged pair, as shown in Fig. 6. Do this for just the
amplifier pairs you wish to run in the bridged mode.
CAUTION: Be sure Power is OFF when connecting or switching the amp for BRIDGED operation.
2. Slide the MODE switch to the BRIDGED position.
NOTE: Do this only on the amplifier pairs you wish to run in the bridged mode!
3. Connect one speaker wire pair between the 4-terminal "SPEAKER" connectors on the PA1235X and the
speakers as shown in Fig. 6. Be sure to use only the two outer terminals marked "+” and "–" on the 4-
terminal connector as shown on the panel for BRIDGED connections.
NOTE: Only one speaker is connected per amplifier pair in the BRIDGED mode!
CAUTION: When operating in the BRIDGED mode (particularly when bench testing the amplifier) do not
make a ground or any other kind of connection to the amplifier speaker terminals other than those to the
individual speakers as shown. Failures caused by inappropriate connections are not covered under the
warranty.
Connecting the REMOTE ON/OFF Jack
As mentioned under "PA1235X PANEL AND FEATURE DESCRIPTIONS", the REMOTE ON/OFF jack allows the
power to the PA1235X to be turned ON and OFF by a remotely applied DC Voltage. Fig. 7 illustrates how a