Background
The Xotic EP Pro takes the concept behind the legendary EP Booster and expands it into a multifunction preamp, boost, tone shaper, and volume pedal.
Like the original EP Booster, the EP Pro draws inspiration from the preamp section of the vintage Echoplex EP-3, a circuit long appreciated for the warmth, dimension, and responsiveness it can add to a guitar signal. The EP Pro builds on that foundation with significantly greater control over gain, EQ, output level, and volume.
A built-in FET gain stage provides up to +20 dB of gain, while dedicated Treble and Bass controls allow the frequency response to be shaped much more extensively than with the original EP Booster. Four internal DIP switches provide additional control over the pedal's full-band and high-frequency response.
The integrated treadle adds continuously variable volume control, allowing the EP Pro to function as an active buffered or passive volume pedal in addition to its boost and preamp functions.
EP Pro vs. EP Booster
The original EP Booster is a compact, straightforward boost and tone-enhancing preamp with a single external Gain control and internal voicing options.
The EP Pro greatly expands that concept. In addition to the EP-inspired FET boost circuit, it provides dedicated Gain, Volume, Treble, and Bass controls, four internal voicing switches, selectable buffered or passive operation, and a full-size volume-pedal treadle.
The EP Booster remains the simpler choice for players looking for a compact always-on tone enhancer or clean boost. The EP Pro is designed for players who want the EP-style preamp character together with extensive tone shaping and real-time volume control in a single pedal.
Controls
Volume — Controls the output level of the boost/preamp circuit. This allows the boosted signal level to be balanced independently from the amount of gain applied by the FET preamp.
Gain — Controls the FET gain stage and provides up to approximately +20 dB of gain. Lower settings can be used for subtle enhancement and additional presence, while higher settings can drive an amplifier or subsequent equipment harder.
Because the boost level and treadle-controlled volume are separate, the EP Pro can add gain and tonal enhancement while still allowing the final output level to be reduced with the volume pedal.
Treble — Provides approximately ±15 dB of high-frequency adjustment. The 12 o'clock position is flat; turning clockwise boosts the treble response, while turning counterclockwise reduces it.
Bass — Provides approximately ±15 dB of low-frequency adjustment. The 12 o'clock position is flat; turning clockwise boosts bass frequencies, while turning counterclockwise reduces them.
Boost On/Off Footswitch — Engages or disengages the EP-style boost and tone-shaping circuit. Depending on the internal bypass setting, disengaging the boost switches either to true/passive operation or to the pedal's active buffered signal path.
Volume Treadle — Provides continuous control over the output level. The volume-pedal function remains available independently of the boost circuit, allowing the EP Pro to serve as both a tone-enhancing preamp and a conventional volume controller.
Active & Passive Volume Pedal Modes
An internal switch allows the EP Pro to operate in either Buffered or True Bypass / Passive mode.
Buffered Mode — When the boost is disengaged, the input signal passes through Xotic's active buffer before reaching the 250K volume potentiometer. This maintains a low-impedance output and helps preserve signal quality when driving longer cables or more complex pedalboards.
True Bypass / Passive Mode — When the boost is disengaged, the signal passes through the 250K volume potentiometer without the active buffer. In this configuration, the EP Pro effectively operates as a passive 250K volume pedal.
This dual-mode design allows the volume-pedal section to be integrated into a wide range of traditional and modern signal chains without requiring the boost circuit to remain active.
Internal DIP Switches
Four internal DIP switches provide additional control over the frequency response of the EP Pro. The switches can be used individually or in combination to adjust full-band boost and high-frequency emphasis.
Full-Band Boost
DIP Switch 1 — Provides a balanced full-band boost of approximately +6 dB.
DIP Switch 2 — Provides a full-band response modeled after the boost and frequency range of the original EP Booster, with approximately +7 dB of gain.
DIP Switches 1 + 2 — Combining both switches provides approximately +7.5 dB of full-band boost.
High-Frequency Voicing
DIP Switch 3 — Introduces a high-frequency shelving boost beginning around 1 kHz and reaching approximately +8 dB.
DIP Switch 4 — Introduces a high-frequency shelving boost beginning around 1.5 kHz and reaching approximately +6 dB.
DIP Switches 3 + 4 — Combining both switches produces a broader high-frequency shelving response beginning around 900 Hz, with approximately +10 dB of boost.
The effects of the internal high-frequency switches become less pronounced as the external Gain control is increased beyond approximately the 12 o'clock position.
Flexible Signal-Chain Placement
The EP Pro can perform different roles depending on where it is positioned in the signal chain.
Before the Amplifier — Placing the EP Pro between the guitar and amplifier allows its FET preamp to increase and shape the signal reaching the amp. This can add warmth, clarity, and responsiveness while also allowing the treadle to control how strongly the amplifier is driven.
In an Effects Loop — The EP Pro can also be used in an amplifier's effects loop, providing volume control after the preamp together with additional tone shaping and boost capability.
Near the End of a Pedalboard — Placing the EP Pro after drive and modulation effects allows it to shape and control the combined signal, functioning as a final preamp, EQ, boost, and master volume before time-based effects or the amplifier.
Before Digital Amp Modelers — The analog FET front end can also be used ahead of digital modeling systems to adjust input level, frequency balance, and playing response before the signal enters the digital device.
Treadle & Construction
Xotic Volume Pedal Mechanism — The treadle mechanism is derived from Xotic's XVP volume pedals and uses a nylon pivot system designed for smooth operation.
Adjustable Treadle Torque — The resistance of the treadle can be adjusted using the external torque nut. Tightening the nut produces a firmer action, while loosening it provides lighter, freer movement.
Aluminum Chassis — The EP Pro uses a lightweight aluminum enclosure designed to provide durability without excessive weight.
Power & LED Indicator
The EP Pro can operate from a standard 9V battery or a regulated external 9–18V DC center-negative power supply.
Power consumption is approximately 10 mA maximum. Xotic estimates approximately 40 hours of continuous operation from an alkaline 9V battery.
Status LED — The LED illuminates when the boost circuit is engaged. If the LED begins flashing, the battery voltage is low and the battery should be replaced.
Features
EP-Inspired FET Preamp — Builds on the analog preamp character that made the original EP Booster one of Xotic's most popular pedals.
Up to +20 dB of Gain — Provides substantial boost for tone enhancement, gain staging, or driving an amplifier and downstream effects.
Treble & Bass EQ — Dedicated ±15 dB controls provide significantly more tone-shaping flexibility than the original EP Booster.
Integrated Volume Pedal — A full treadle allows real-time control over overall volume independently of the boost setting.
Active or Passive Volume Operation — An internal switch allows the volume section to operate with Xotic's active buffer or as a passive 250K volume pedal.
Four Internal Voicing Switches — Provide additional full-band and high-frequency boost options for customizing the preamp response.
Adjustable Treadle Resistance — Allows the feel of the volume pedal to be tailored to individual preference.
9–18V Operation — Supports standard 9V operation as well as higher-voltage external power.
Specifications
Model: EP Pro
Effect Type: Preamp / Boost / Volume Pedal
Controls: Volume, Gain, Treble, Bass
Maximum Gain: Up to +20 dB
Treble EQ: ±15 dB
Bass EQ: ±15 dB
Internal Tone Controls: 4 DIP switches
Volume Pedal: Active buffered or passive 250K operation
Bypass: Selectable True Bypass / Buffered operation
Input Impedance: 500 kΩ with Boost or Buffer active
Passive Volume Potentiometer: 250 kΩ
Output Impedance: 2 kΩ
Nominal Input Level: -20 dBV
Nominal Output Level: -20 dBV
Power Consumption: 10 mA maximum
Power: 9V battery or regulated 9–18V DC
Polarity: Center-negative
Battery: One 9V battery (006P)
Estimated Battery Life: Approximately 40 hours with an alkaline battery
Connections: TS input and output; not compatible with TRS plugs
Dimensions: 8.27" × 3.94" × 2.64" (210 × 100 × 67 mm)
Weight: 2.16 lb. (980 g)
