Radial Engineering EXTC-SA REAMP, Руководство пользователя

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Radial Engineering Ltd. EXTC-SA
True to the Music
®
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.
INPUT
+4dB
OUTPUT
+4dB
EXTC-SA
HIGH IMPEDANCE LOOP-B
SEND RETURN
PEDAL PEDAL
HIGH IMPEDANCE LOOP-A
SEND RETURN
PEDAL PEDAL
BLEND
PHASE
CANCELLATION
OUTPUT
+4dB
INPUT
+4dB
EXTC-SA
PEDAL
SEND RETURN BLEND
NORMAL
PHASE
PHASE
INVERT
PHASE
NORMAL
PHASE NORMAL
PHASE
NORMAL
OUTPUT
+4dB
PHASE INVERTING PEDAL
PHASE INVERTING PEDAL
INPUT
+4dB
EXTC-SA
PEDAL
SEND RETURN BLEND
NORMAL
PHASE
PHASE INVERT
PHASE
INVERT
PHASE
NORMAL
OK
DRY
DRY
DRY
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
pedals and guitars. The other cool ‘trick’ inside the EXTC-SA is the blend control. This mixes
the original dry signal with the newly introduced effects created by the pedals.
Something to think about here is how some effect pedals will reverse the polarity of the
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
where one pedal “B” is inverting the polarity creating cancellation where two out-of-phase
signals come together.
INPUT
+4dB
OUTPUT
+4dB
EXTC-SA
HIGH IMPEDANCE LOOP-B
SEND RETURN
PEDAL PEDAL
HIGH IMPEDANCE LOOP-A
SEND RETURN
PEDAL PEDAL
BLEND
PHASE
CANCELLATION
OUTPUT
+4dB
INPUT
+4dB
EXTC-SA
PEDAL
SEND RETURN BLEND
NORMAL
PHASE
PHASE
INVERT
PHASE
NORMAL
PHASE NORMAL
PHASE
NORMAL
OUTPUT
+4dB
PHASE INVERTING PEDAL
PHASE INVERTING PEDAL
INPUT
+4dB
EXTC-SA
PEDAL
SEND RETURN BLEND
NORMAL
PHASE
PHASE INVERT
PHASE
INVERT
PHASE
NORMAL
OK
DRY
DRY
DRY
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
back to normal phase.
INPUT
+4dB
OUTPUT
+4dB
EXTC-SA
HIGH IMPEDANCE LOOP-B
SEND RETURN
PEDAL PEDAL
HIGH IMPEDANCE LOOP-A
SEND RETURN
PEDAL PEDAL
BLEND
PHASE
CANCELLATION
OUTPUT
+4dB
INPUT
+4dB
EXTC-SA
PEDAL
SEND RETURN BLEND
NORMAL
PHASE
PHASE
INVERT
PHASE
NORMAL
PHASE NORMAL
PHASE
NORMAL
OUTPUT
+4dB
PHASE INVERTING PEDAL
PHASE INVERTING PEDAL
INPUT
+4dB
EXTC-SA
PEDAL
SEND RETURN BLEND
NORMAL
PHASE
PHASE INVERT
PHASE
INVERT
PHASE
NORMAL
OK
DRY
DRY
DRY
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