Overview - Radial Engineering EXTC-SA REAMP User Manual

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OVERVIEW

The Radial EXTC-SA is a professional audio interface that takes a +4dB balanced line-level
signal and converts it to a guitar-level effects loop and then re-converts it back to a +4dB
balanced line-level signal. In other words, you send in a balanced signal from your recorder,
adjust the loop send level that drives the pedals. Set the return level from the pedals as it
comes back and send the resulting signal to your recording system.
EXTC-SA
DRY
INPUT
+4dB
Although simple in principle, the key to the EXTC-SA's performance is how quietly it does
the task. This is achieved by employing full sized discrete electronic components, class-A
circuitry and transformer isolation to help eliminate the hum and buzz that is common with EXTC-SA
pedals and guitars. The other cool 'trick' inside the EXTC-SA is the blend control. This mixes
DRY
INPUT EXTC-SA
the original dry signal with the newly introduced effects created by the pedals. PHASE NORMAL
+4dB
DRY
INPUT
Something to think about here is how some effect pedals will reverse the polarity of the
+4dB
signal passing through them. When you mix a dry signal with a wet signal and one is polarity
reversed, you will of course end up with cancellation. The diagram below illustrates a setup
EXTC-SA
where one pedal "B" is inverting the polarity creating cancellation where two out-of-phase
DRY
INPUT
signals come together.
+4dB
EXTC-SA
DRY
INPUT
EXTC-SA
PHASE INVERT
+4dB
DRY
INPUT
PHASE NORMAL
+4dB
EXTC-SA
DRY
INPUT
PHASE NORMAL
+4dB
The PHASE INVERT switch plays an important role by ensuring both the dry and wet signals
are in phase. The next diagram shows how the PHASE INVERT switch reverses the signal
polarity before it gets to the offending pedal. Pedal "B" gets tricked into re-inverting the signal EXTC-SA
back to normal phase.
DRY
INPUT
PHASE INVERT
+4dB
EXTC-SA
DRY
INPUT
PHASE INVERT
+4dB
Radial Engineering Ltd.
SEND RETURN
PEDAL PEDAL
HIGH IMPEDANCE LOOP-A
SEND
PHASE
NORMAL
SEND RETURN
PEDAL
PHASE INVERTING PEDAL
PEDAL PEDAL
HIGH IMPEDANCE LOOP-A
SEND RETURN
PEDAL PEDAL
HIGH IMPEDANCE LOOP-A
SEND
PHASE
INVERT
SEND
PHASE
PEDAL
NORMAL
PHASE INVERTING PEDAL
PEDAL
PHASE INVERTING PEDAL
SEND
PHASE
NORMAL
PEDAL
PHASE INVERTING PEDAL
SEND
PHASE
INVERT
PEDAL
PHASE INVERTING PEDAL
SEND
PHASE
INVERT
PEDAL
PHASE INVERTING PEDAL
SEND RETURN
PEDAL PEDAL
HIGH IMPEDANCE LOOP-B
RETURN
PHASE
INVERT
SEND RETURN
PEDAL PEDAL
HIGH IMPEDANCE LOOP-B
SEND RETURN
PEDAL PEDAL
HIGH IMPEDANCE LOOP-B
RETURN
PHASE
NORMAL
RETURN
PHASE
INVERT
RETURN
PHASE
INVERT
RETURN
PHASE
NORMAL
RETURN
PHASE
NORMAL
2
True to the Music
BLEND
NORMAL
PHASE
PHASE
CANCELLATION
BLEND
BLEND
BLEND
NORMAL
PHASE
PHASE
NORMAL
NORMAL
BLEND
PHASE
PHASE
CANCELLATION
OK
BLEND
NORMAL
PHASE
PHASE
CANCELLATION
BLEND
NORMAL
PHASE
PHASE
NORMAL
BLEND
OK
NORMAL
PHASE
PHASE
NORMAL
BLEND
OK
OUTPUT
+4dB
OUTPUT
+4dB
OUTPUT
+4dB
OUTPUT
+4dB
OUTPUT
+4dB
OUTPUT
+4dB
OUTPUT
+4dB
OUTPUT
+4dB
OUTPUT
+4dB
EXTC-SA