Variable Limiter Control; Limiter Active Led; Master (Volume) Control; Speaker On/Off Switch - SWR 750x Bass Amplifier 750x Owner's Manual

The Effects Blend circuit is similar to that used on recording consoles with the effects loop on a "side
chain" to the normal circuit. Unless the control is set to the full "wet" position, you will always get the full
sound of your instrument AND get the diversity an effects unit offers. This circuit is also effective in reduc-
ing noise generated by effects units because it is located after the gain stages in the preamp.
The Effects Blend control functions only when the Effects Loop is being used. It is activated when a 1/4"
phone plug is inserted into the Effects Receive jack. (For more information, please see the heading titled
"Effects Loop" in the "Rear Panel Features" section later in this manual.)

Variable Limiter Control

The 750x's soft knee-type limiter is there to help you protect your power amp from harmful states of opera-
tion. The circuit is located after the Master Volume and before the power amplifier, so it's driven by the
Master Volume control. Its threshold (starting point) is preset by the factory so that you can get maximum
overall apparent volume without unduly overdriving (or "clipping") the power amplifier—which, over time, can
eventually damage the unit's internal circuitry, as well as damage speakers connected to your amp.
Using the control is simple. Turning the Limiter Control clockwise (toward "MAX") increases the amount of
limiting on your signal, while turning it counter-clockwise decreases the amount. When trying to find the
highest possible level of power amp operation under clipping, simply use the Master Volume and Limiter
Controls together to find: a) The highest setting possible on the Master Volume; and b) The lowest possible
setting of the Limiter... all while hearing no power amp distor tion whatsoever.

Limiter Active LED

When the threshold (starting point) of the Limiter circuit is reached, the Limiter Active LED will light, indicat-
ing that the Limiter Circuit is active and helping to protect your power amplifier and speakers from power
amp clipping. The Limiter LED will not illuminate when playing at levels not high enough to engage the cir-
cuit.
Note: If you have the Limiter set at "MIN" and you hear a loud, sharp distortion present in your
sound—and the Preamp Clip LED is not lighting up—engage the Limiter by turning up the control. If
the distortion goes away, you were probably clipping the power amp, which is not a good thing.
Remember, the Limiter circuit is there to protect your amplifier from such a state of operation.

Master (Volume) Control

The Master (meaning "Master Volume") control adjusts the level being sent to the power amplifier in your
750x—it controls the overall volume of the unit. Turning the control counter-clockwise reduces the overall
level, while turning the control clockwise boosts the overall level.
Two notes: The Master control never affects the level present at the various audio output jacks on the rear
panel—it only affects the level being sent to the power amplifier, and subsequently, your speaker outputs
only. Also, losses caused by external effects units can be recovered by increasing the Master control.

Speaker On/Off Switch

Setting the Speaker On/Off Switch up to the "On" position allows the signal from the amplifier to be heard
through any speaker enclosure(s) connected to the Speaker Output section of the 750x. Setting the
Speaker On/Off Switch down to the "Off" position disables the speaker output section. This feature allows
you to:
1. Use the Balanced (XLR) Output without using the internal speakers. This is especially useful in
recording when you are "miking" the speakers and only a direct signal is required for the moment.
2. Tune up without making sound onstage (and interfering with other band members) while using the
Tuner Out feature.
3. Defeat the "pop" you sometimes get when changing and/or unplugging instruments from the unit
(especially if you sometimes forget to disconnect your instrument cable from the amplifier before discon-
necting it from your bass, something that's always a good idea).
4. Defeat the "pop" present upon powering up the unit (though it causes no harm to the unit and/or
your speakers).
NOTE: If you do not hear any sound when you plug in and your system is properly connected, check
the position of this switch!
750x OWNER'S MANUAL • 9