1)Footswitch—The Footswitch jack on the V50 is a stereo jack that con- nects the V50 footswitch to the amplifier. It uses a special circuit to decode the three switches through a simple stereo cable. In an emergency, a mono instrument cable can be used to allow footswitching of the channels only. In this setup, the LEDs will not be visible, but at least the footswitch will select Rhythm or Lead channels.
2)Ground Lift—The Ground Lift switch disconnects pin 1 of the XLR Direct Out jack to eliminate a “ground loop” hum. A ground loop can exist when the V50 and the mixer it is plugged into are connected to grounded outlets that are in physically different locations and/or on different circuits, and should only be used if there is an audible hum. Pressing the ground lift does not disconnect the ground connection from the V50’s chassis.
3)Direct Out—The XLR Direct Out jack is designed to connect the V50 ampli- fier to a recording or live mixer. The output is speaker-emulated, and mim- ics the sound of the Celestion Vintage 30 loudspeaker. This output is very useful for direct recording, and especially helpful for live applications since it eliminates a live microphone on stage and the resulting feedback potential. The V50 amplifier should never be operated without a speaker plugged into a speaker jack.
4)Direct Volume—Sets the level of the speaker-emulated direct out. This control should be set as high as possible for the best signal-to-noise ratio.
5)Boost Volume—The Boost Volume knob controls the amount of footswit- chable boost, and is particularly useful for solos. It will provide up to 10dB of “Master Volume” boost, and boosts both channels. The tone is optimized to increase the volume without sacrificing too much headroom in the power amp, so the resulting solo cuts through. The boost is active if the footswitch is unplugged.
6)Effects Return—This 1⁄4” jack breaks the flow of amplifier signal to allow an external effects device to “return” to the amp. The Return jack can also be used for a power amp input, when using an external preamp. This all-tube ef- fects loop is known as a “series” loop, since it breaks the path of the amplifier and “inserts” the effect in series.
7)Effects Send—This 1⁄4” jack delivers a tube-driven preamp signal to ex- ternal effects devices. It can be used to send the signal to another amplifier to run multiple amps. Connecting a 1⁄4” plug does NOT break the flow of the amplifier signal. To connect two Defender amplifiers in stereo, a stereo effects device can be driven from one Defender amp’s Send, and the device’s two stereo outputs can be returned to both Defender amps’ Returns.
