SP25M-PRO Aero Electronic User Guide

SP25M-PRO Aero
Electronic User Guide

  • Written instructions

  • Video tutorials and demos

  • Technical Specifications

  • Frequently Asked Questions


Congratulations on your purchase of the Mission SP25M PRO Aero. This product is designed to be intuitive to setup and operate, and to provide many years of trouble free service. However, we recommend that you take a few moments to read through this User Guide in order to get the best possible experience with your new pedal.


The SP-25M-PRO has dual 25K outputs with polarity selection and a momentary toe switch, compatible with many devices for guitar, keyboards, acoustic instruments both live and in the studio.


The SP25M has three 1/4″ output connections. The two outputs on the left side marked OUT 1 and OUT2 are the expression pedal outputs. Connect one or both of these to the expression pedal input(s) of the device you wish to control. 1/4″ TRS (stereo) cables are required; regular TS instrument cables will not work.

Both expression outputs will be controlled simultaneously. It is not possible to switch the pedal between different outputs. For switchable outputs, the SP25M PRO Aero can be used with the Expressionator multi expression controller.

The single output on the right side marked OUT3 is the switch output. This can be connected with  a 1/4″ TS  cable to a compatible device that supports an external momentary TS switch such as a MIDI controller or multi-effect unit. The switch output may be left unconnected if it is not required.

After connecting the cables, follow the instructions in the user manual for the device you are connecting to determine if it should be enabled or calibrated for expression pedal use.


The expression pedal and switch functions are passive, and the SP25 PRO Aero does not require a power supply or battery. The power connection input marked 9v DC is not required in this pedal model, and a blank is installed.


There is no global standard for expression pedals; different manufacturers and products can require different types of expression pedal. The SP25M Pro Aero expression outputs are 25K Ohm TRS. These will work with many, but not all devices. Some devices will still work with a 25K expression pedal but required a reversed polarity where the ring of the TRS is connected to the potentiometer wiper.

The SP25M PRO Aero factory defaults are set so that OUT1 and OUT2 are tip to wiper. For use with ring to wiper devices, the polarity of the expression pedal may be reversed. Remove the 4 rubber feet and metal baseplate. Locate the polarity switches marked SW1 and SW2.

Factory Default
SW1 – OUT1 – Right – Tip to Wiper
SW2 – OUT2 – Right – Tip to Wiper

Setting either switch to the left position will reverse the polarity to ring to wiper on the corresponding output.

Make sure to replace the baseplate and feet after setting the polarity.

Safety Instructions

Read, Keep & Follow these instructions
Heed all warnings
Clean only with dry cloth
Do not use this apparatus near water

Do not expose the apparatus to dripping or
splashing and ensure that no objects filled with
liquids, shall be placed on the apparatus

WARNING: To reduce the risk of fire or electric
shock do not expose this apparatus to rain or

Unplug this apparatus during lightning storms or
when unused for long periods of time

Do not block any ventilation openings. Install in
accordance with the manufacturer’s instructions

Only use attachments/accessories specified by
the manufacturer

Prolonged listening at high volume levels may
cause irreparable hearing loss and/or damage.
Always be sure to practice “safe listening.”

Refer all servicing to qualified service personnel.
Service is required when the apparatus has been
damaged in any way, such as:

Power-supply cord or plug is damaged
Liquid has been spilled or objects have fallen
into the apparatus
The unit has been exposed to rain or moisture
The unit is dropped or the enclosure is
The unit does not operate normally or changes
in performance in a significant way

Dismantling, rewiring, removing components or
otherwise altering the function of the unit may
cause unexpected behavior and will invalidate
the warranty.

Quick Start - Polarity Switches