User Manual

SA247 True Spring Reverb User Guide 20
Expression Control
The True Spring’s effects parameters can be controlled directly by an expression pedal or Hot Hand
connected to the CONTROL INPUT port.
Expression Pedal Input
Many parameters of the True Spring Reverb can be controlled with the Source Audio Dual Expression
Pedal or Reflex Universal Expression Pedal. Connect either of these expression pedals to the Control
Input port using a 1/8” (3.5 mm) TRRS cable. By default external expression pedals control the reverb
send.
Source Audio’s expression pedals are configured as follows: the tip connection is power, the first ring
is the X axis expression signal, the second ring is the Y axis expression signal, and the sleeve
connection is ground.
Third party expression pedals can be used as well, as long as they have a 1/8” (3.5 mm) TRS (Tip Ring
Sleeve) plug with power on the tip, expression (the wiper of the potentiometer) on the ring, and
ground on the sleeve, as seen in the diagram below.
Expression pedals with TS (Tip Sleeve) plugs will not work correctly with the True Spring.
The resistance of the expression pedal does not matter. The True Spring will automatically adjust
itself to the range of the expression pedal when it is configured.
Although the CONTROL INPUT port expects a 4-contact TRRS plug, it is still possible to use a 3
rd
party
expression pedal with a 3-contact TRS plug (Note: you should make sure the expression pedal’s TRS
configuration is the same as the graphic above). Use a 3-contact 1/4” to 1/8” (3.5mm) TRS plug
converter, the expression pedal’s output will be connected to the True Spring’s X expression input.
Ground Power
Y Exp X Exp
Ground Power
Expression