Electro-Harmonix LPB-3 Linear Power Booster Pedal

The Electro-Harmonix LPB-3 Linear Power Booster & EQ takes the concept behind the original 1968 LPB-1—the effect that launched Electro-Harmonix—and expands it into a much more flexible boost and tone-shaping pedal. With up to 33dB of clean gain, an active three-band EQ, and a fully parametric midrange section, the LPB-3 can handle everything from subtle level matching and clean boosting to aggressive amp pushing and detailed EQ work.

The Boost control sets the pedal's output level, while Pre-Gain adjusts the signal level before it reaches the EQ section. Pre-Gain provides up to 20dB of input gain, making it possible to control how hard the EQ and output stages are driven independently. The MAX switch sets the LPB-3's maximum total gain to either 20dB or 33dB; the lower setting provides greater dynamic range, while 33dB mode is available when substantially more level or amplifier saturation is needed.

The active EQ gives the LPB-3 considerably more control than a conventional clean boost. Bass boosts or cuts frequencies below 240Hz, while Treble adjusts frequencies above 3.25kHz. The midrange section combines Mid Level with a sweepable Mid Frequency control covering 240Hz to 3.3kHz, allowing you to target anything from low-mid body to upper-mid attack.

A dedicated Q switch changes the width of the midrange adjustment. LOW provides a broader, rounder EQ curve that affects a wider frequency range, while HIGH narrows the bandwidth for more precise boosts and cuts. This makes the LPB-3 useful not only as a volume boost, but also for tightening low end, adding presence, emphasizing a solo frequency, compensating for different guitars, or reshaping the signal before another gain pedal.

Internally, the LPB-3 operates from extended ±15V power rails for increased headroom even though it runs from a standard 9V pedal supply. An internal slide switch lets you choose between true bypass and buffered bypass, with true bypass selected from the factory.

Key Features

• Modern evolution of the original 1968 Electro-Harmonix LPB-1
• Up to 33dB of clean boost
• Selectable 20dB / 33dB maximum gain
• Pre-Gain control provides 0–20dB of input gain
• Active three-band EQ
• Parametric midrange section
• Mid Frequency sweep from 240Hz–3.3kHz
• LOW / HIGH Q selector for broad or narrow midrange shaping
• Bass boost/cut below 240Hz
• Treble boost/cut above 3.25kHz
• Internally boosted ±15V power rails for extended headroom
• Internally selectable true or buffered bypass
• Can boost instrument signals toward line level for recording and other applications
• Compact Nano-sized enclosure

Specifications

• Effect Type: Clean Boost / Preamp / EQ
• Circuit: Analog
• Controls: Boost, Pre-Gain, Mid Level, Mid Frequency, Treble, Bass
• Switches: MAX 20dB / 33dB, Q Low / High
• Maximum Boost: 33dB
• Pre-Gain Range: 0–20dB
• Mid Frequency Range: 240Hz–3.3kHz
• Treble EQ: Above 3.25kHz
• Bass EQ: Below 240Hz
• Input: 1 x 1/4"
• Input Impedance: 1MΩ
• Maximum Input Level: +20dBu
• Output: 1 x 1/4"
• Output Impedance: 660Ω
• Maximum Output Level: +22dBu
• Audio: Mono
• Bypass: Selectable True Bypass / Buffered Bypass
• Power: 9V DC, center-negative
• Current Draw: 120mA
• Included Power Supply: EHX 9.6VDC / 200mA adapter
• Minimum Recommended Supply Current: 150mA
• Maximum Supply Voltage: Do not exceed 12V DC
• Battery Operation: No
• Dimensions: 4.5" x 2.75" x 2.1"
• Year Released: 2024
• UPC: 683274012599