f. EXP MAX2 (various): Allows you to set the maximum range of the
expression pedal sweep. The units that appear with this parameter
will change to match the units of the parameter selected above in 4.
g. EXP SWITCH (OFF, WAH): Selects the ON/OFF function which is
controlled by the EXP SWITCH jack.
It is recommended to use a pedal with a linear taper pot, the resistance of
which is not critical, since the circuit is just reading the ratio of two voltages.
The ideal pedal for this is the Mission Engineering model EP1-KP
. It has
two jacks, one is TRS (3 conductors) labeled OUT 1 for the potentiometer
(pot). Connect this jack via ¼” TRS cable to the EXP PEDAL jack on the
back of the Theta Pro. The second jack on the EP1-KP is labeled OUT 2.
Connect this jack via ¼” TS (2 conductor, standard jumper cable) to the EXP
SWITCH jack on the back of the Theta Pro, and the switch in the toe of the
pedal can be used to turn on the WAH. Other pedals can be used, but for a
standard volume pedal you will need a ‘Y’ cord which has a single ¼” TRS
(tip-ring-
sleeve) jack at 1 end and two ¼” mono jacks at the other end,
assuming your volume pedal has separate IN and OUT jacks (sometimes
labeled INST and AMP). The ring of the EXP PEDAL jack supplies 3.3 volts
DC to the IN jack on the pedal, and the tip of the EXP PEDAL jack reads the
wiper voltage on the OUT or AMP jack of the pedal. If you connect them
backwards you won’t damage anything, but the parameter change will be very
abrupt in the bottom part of the pedal travel. Connecting them the other way
will result in most of the parameter change occurring at the top of the pedal
travel, if an audio taper pot is used. For most parameters, especially the
WAH frequency, a pedal with a linear taper pot is recommended for correct
functionality.
N) Title Edit Function
This displays the preset title. The PARAM knob selects the character
position to be edited, which moves the cursor under the character
selected. There are 16 character positions. The VALUE knob then
selects the particular letter, number, or symbol. When you are finished
editing the title, don’t forget to press 2
nd
, then STORE to save it.
O) Dump/Load Function
a. DUMP PRESET (ALL, 1 to 224): Selects the preset to be dumped
as a midi sysex message to the MIDI OUT jack. A single preset
can be dumped, or all presets. If ALL is selected, the GLOBAL
data, followed by all 224 presets, followed by all 124 songs will be
dumped. To initiate the dump, press 2
nd
, followed by STORE. A
“DUMPING …” message will be displayed, followed by “DUMP