WARNING! Turn the Master Power switch Off
and unplug it before making or breaking any
signal connections!
2-Channel Mode
This setup is recommended if your subwoofer will be used
in a 2-channel only system. When a signal is connected to
the subwoofers Left In/Right In, the Low Pass Filter control
is active.
Signal Connection (see figure 4):
1 Connect the left out/right out from your preamp/receiver
to the Left In/Right In of the subwoofer. Use quality RCA
interconnects. If your preamp/receiver only has one set of
outputs you need to obtain Y adapters from your dealer.
Recommended Control Settings (see figure 5):
1 Calculate the number equal to 70% of your main loud-
speaker’s lowest frequency rating. Set the Low Pass Filter
switch to the closest setting below the resulting number.
2 Play familiar music with bass content. Increase the Level
control until the music has deep extended bass. Be
careful to avoid levels that become overwhelming.
3 Try the phase control in different settings until the best
blending is obtained. If you are using the subwoofer to
augment other MartinLogan products, we suggest start-
ing with the phase set at 90°.
4 If you have completed steps 1–3 and still have weak
or boomy bass, adjust the 25Hz Level and 50Hz Level
knobs to compensate for these anomalies. Experiment
with the controls and listen to the effects. Try to find
a position that sounds correct to you. Experiment by
changing the Level control while adjusting these knobs.
Find a position that gives you deep extended bass and
good blending with your main speakers.
Figure 4. Signal connection for 2-channel mode.
Figure 5. Adjust these controls for 2-channel mode.
Controls and Connections 9
