EHX Q-Tron Plus Envelope Filter with Effects Loop

The EHX Q-Tron Plus – Dynamic filter funk with flexible routing and rich tonal control

Classic envelope filter with expanded flexibility

The EHX Q-Tron Plus builds on the legacy of the original Q-Tron with the addition of a dedicated effects loop and a response switch, giving you deeper control over your envelope filter tones. With the same rich, analog filter sweep and funk-infused response, this pedal adds new creative possibilities for tone stacking and modulation by allowing you to place external effects directly between the preamp and filter sections.

Powerful effects loop for tone-shaping creativity

The built-in FX loop gives you the ability to insert distortion, modulation, delay, or octave effects after the preamp without altering the sensitivity of the envelope. This routing preserves the dynamic response of the envelope follower while adding unique textures—try a Micro POG followed by a delay to discover entirely new sounds. The Q-Tron Plus makes it easy to experiment and innovate with your effects chain.

Switchable response, sweep, and filter modes

A three-mode filter selector lets you toggle between low pass, band pass, and high pass settings, while a sweep direction switch allows for upward or downward filtering. You can also select between high and low frequency sweep ranges for fine-tuning your tone. The response switch gives you two dynamic behaviors: the fast, snappy reaction of the original Q-Tron or a slower, vowel-like attack for smoother transitions.

Customizable tone control with gain, boost, and Q settings

The adjustable gain knob lets you dial in the input level for optimal envelope sensitivity, and the boost switch adds a punch of output to push your amp or other pedals. A dedicated resonance (Q) control allows you to set the filter peak from subtle to dramatic, shaping your tone from mellow funk swells to aggressive wah-like growls.

Rugged analog design with true bypass

Built with a road-ready die-cast enclosure and equipped with true bypass, the Q-Tron Plus ensures your tone remains untouched when the effect is disengaged. It runs on a 24VDC power supply (included) to drive the analog circuit for full, vibrant filtering with rich harmonic content.

Specifications

• Circuit: Analog

• Bypass: True Bypass

• Audio: Mono

• Effects Loop: Yes – FX Send and Return between preamp and filter

• Filter Modes: Low Pass, Band Pass, High Pass

• Sweep Direction: Up/Down

• Response Modes: Fast or Slow envelope attack

• Frequency Sweep Range: Hi/Lo

• Resonant Peak Control: Adjustable Q

• Gain Control: Adjustable gain knob with boost switch

• Power Supply: 24VDC–100mA power adapter included

• Current Draw: 35mA

• Dimensions: 5.75" x 4.75" x 2.5"

• Year Released: 2008

• UPC: 683274010670

This effects pedal ships fully insured with signature required.