Lehle DUAL EXPRESSION User Manual

6
LEHLE GmbH · Germany · www.lehle.com · support@lehle.com
HOW DOES AN EXPRESSION PEDAL WORK?
An expression pedal usually controls a
specific value of an eects device.
For example you want to use your foot
to control the mix amount of your delay
pedal.
In most cases your eects pedal oers a
control / potentiometer that cares about
the mix amount of your delay pedal. This
potentiometer will now be replaced by an
external expression pedal, that also usu-
ally works with a potentiometer.
The procedures, how this is being done,
are as complicated as they are varied.
Typically, your eects pedals send a volt-
age of 3.3 V or 5 V to the potentiom-
eter of the expression pedal. The poten-
tiometer as a variable resistor routes a
part of the voltage back. The sent back
voltage – also called control voltage – is
being changed by the position of the po-
tentiometer. The eects pedal measures
the control voltage and thus can modify
a parameter. In the above-mentioned ex-
ample the mix amount would be changed.
The individual cables and polarities in
summary:
RTS: the control voltage is being applied
to the ring of the TRS jack.
TRS: the control voltage is being applied
to the tip of the TRS jack.
TS: here the eects pedal measure the
voltage between sleeve and tip of the TS
jack.
Instead of stereo jacks or mono jacks we
are talking rightly about TRS and TS jacks.
!

Lehle DUAL EXPRESSION Specifications

General

Brand	Lehle
Model	DUAL EXPRESSION
Category	Music Pedal
Language	English