SWR 350x Operating Instructions Manual page 16

Effects Loop (for external effects devices)
As mentioned previously in the "Effects Blend Control" section of the manual, the Effects Blend circuit in
your 350x is similar to that used on recording consoles, with the effects loop on a "side chain" to the nor-
mal circuit. Unless the Effects Blend control is set to the full "wet" position, you will always get the full
sound of your instrument AND get the diversity an external effects unit offers. Use of the effects loop will
reduce the noise generated by external effects units (as compared to using the effect between your instru-
ment and the input jack, though many people use it in this fashion anyway). This is because the loop is
after the preamp gain stages.
The Effects Loop is compatible with most individual or multi-effect external effects devices. Many effects
devices on the market have input level adjustments. For instance, some units have a switch that you can
set for either -20 dB or +4 dB. In all cases, these should be set for 0 dB (if available) or +4 dB. The level
going to your effect is controlled by the Gain control on the front panel.
Note: The Effects Loop is used in conjunction with the Effects Blend control on the front panel. When
the Effects Blend Control is in the full counter-clockwise ("DRY") position, no effects will be heard.
This is normal.
Connecting An External Effects Device To The 350x Effects Loop
Obtain two high-quality shielded patch cables, preferably as short as possible. Route them in the most
direct way possible. (Running patch cables over the top of the 350x – as with any amplifier – can induce
hum in the cables and is not recommended.) Take one cable and connect it from the Effects Send jack on
the 350x to the input of your external effects device. Take the second cable and connect it from the out-
put of your external effects device to the Effects Return jack on your 350x. To set levels, follow the
instructions as previously listed in the "Effects Blend Control" heading under "Front Panel Features."
And, just so there isn't any confusion, the Effects Loop has nothing to do with the SubWave™ effect
onboard your 350x. It only is used in conjunction with an external effects device.
Effects Send
This jack's primary function is to send a post-EQ-and-SubWave™ signal to an external effects device for
use in the 350x Effects Loop. However, it can also be used as:
1. A line level output for use in conjunction with an additional (slave) power amp—such as SWR's Power
750.
2. An unbalanced output suitable for recording or live mixing board purposes.
The output impedance of the Effects Send jack is 100 Ohms.
Effects Receive
This jack's primary function is to complete the Effects Loop circuit by routing the post-external-effects
device signal back into the power amp of the 350x, where it can be blended back in with the original sig-
nal by using the Effects Blend control on the front panel. However, it can also be used as:
1. A power amp input jack. If, for some reason, you wished to bypass the entire front end and use the
350x strictly as a power amp, you could take the output of whatever line-level audio source you wished
and connect it to this jack. Then, set the Effects Blend control to the full clockwise ("WET") position.
Use the Master control to set the overall level, and your 350x is now a power amp only.
2. An input for pre-recorded music, for playing along and practicing purposes. To accomplish this, insert
a CD player or other sound source into the Effects Receive jack. (It must be a MONO 1/4" plug that
goes into this input, so you'll have to use a stereo-to-mono cable adapter of some kind.) You can adjust
the level of recorded music versus the "live" sound of your instrument by using both the Effects Blend
control (the more clockwise the control, the more pre-recorded music signal you'll hear) and the volume
control of your CD (or other) audio source. The mixed sound will be heard through your speakers.
Besides pre-recorded music, this is also an excellent way to practice along with a drum machine.
Input impedance of the Receive jack is 27k Ohms minimum.
Note: Inserting a plug into the Effects Receive jack activates the Effects Blend control. The control
receives this command through the ground created by the phone plug making contact with the jack.
The plug must be a mono plug (tip and ground). If you have a stereo plug only, it will be necessary to
tie the ring and the ground together.
16 • 350x