EHX Q-Tron+ Settings Guide
The Electro-Harmonix Q-Tron+ is an envelope filter — a dynamic wah-like effect controlled by the player's picking attack rather than a rocker pedal. Harder picking opens the filter further; lighter picking keeps it closed. The original Q-Tron was Bootsy Collins's bass pedal; the guitar version became essential for funk, soul, and psychedelic rock. A dedicated effects loop insert lets an additional effect (compression, delay) be added inside the filter circuit.
The best EHX Q-Tron+ settings start with: Sensitivity at 5/10, Q at 5/10. Adjust from there based on your amp, guitar, and room volume. For Funk: Sensitivity 6/10, Q 7/10.
⚡ Start Here — Recommended Settings
| Control | Starting Position | Range |
|---|---|---|
| Sensitivity | 5/10 | Low → High |
| Q | 5/10 | Broad → Sharp |
These are universal starting points. Adjust based on your amp, guitar, and room. Scroll down for genre-specific settings and artist-documented positions.
What Each Control Does
Recommended Starting Settings
Safe starting positions for any style. Adjust from here based on your amp and room.
All values on a 0–10 scale. These are starting points — fine-tune by ear.
Settings by Genre
BP mode, high Q — the classic envelope filter character. Sensitivity 6 opens the filter on medium-hard picking. Q 7 produces a pronounced, dramatic filter sweep. For funk rhythm work, dig in hard on the upbeat accents and let lighter ghost strokes keep the filter closed.
LP mode, moderate Q — warmer, smoother envelope filter for soul. The low-pass character produces a fatter, less aggressive wah. Sensitivity 5 requires a medium pick attack to open the filter consistently.
HP mode, high Q — a trebly, dramatic filter for psychedelic and experimental playing. The high-pass mode emphasises the upper harmonics of the filtered signal, producing a bright, almost synthesiser-like character with a sharp filter resonance.
BP mode at moderate Q gives a usable, less extreme envelope-filter texture for rock rhythm playing, where a full funk-style filter sweep would be too dramatic for the context.
LP mode with a wide Q rolls off the upper harmonics for a rounder, bass-adjacent filtered tone, closer to the pedal original bass application than a typical guitar wah setting.
Tips & Common Mistakes
- Envelope filters are extremely sensitive to guitar volume. Running a compressor before the Q-Tron+ standardises pick attack level, making the filter open consistently. A compressor after the filter smoothes out the volume jump when the filter opens dramatically.
- The effects loop insert on the Q-Tron+ accepts any effect into the filter feedback path. A subtle digital delay in the loop (70ms, 1 repeat) adds a rhythmic echo that reinforces the groove character of the filter.
- Sensitivity should be matched to pickup output — high-output humbuckers generally need a lower Sensitivity setting than single coils to avoid the filter opening on every note regardless of playing dynamics.
- Mode selection (LP, BP, HP) is a bigger tonal decision than Q or Sensitivity — settle on the mode for a given part first, then fine-tune Q and Sensitivity within that mode rather than adjusting all three at once.
- For the most dynamic, expressive funk playing, practice varying pick attack deliberately rather than setting Sensitivity once and playing at constant force — the filter dynamic range is the actual expressive tool, not a fixed EQ curve.
FAQ
EHX Q-Tron+ — Common Questions
Best starting settings for EHX Q-Tron+: Sensitivity at 5/10, Q at 5/10. Adjust from there based on your guitar, room, and playing style.
For Funk: Sensitivity 6/10, Q 7/10. BP mode, high Q — the classic envelope filter character. Sensitivity 6 opens the filter on medium-hard picking. Q 7 produces a pronounced, dramatic filter sweep. For funk rhythm work, dig in hard on the upbeat accents and let lighter ghost strokes keep the filter closed.
For Soul / R&B: Sensitivity 5/10, Q 5/10. LP mode, moderate Q — warmer, smoother envelope filter for soul. The low-pass character produces a fatter, less aggressive wah. Sensitivity 5 requires a medium pick attack to open the filter consistently.
Sensitivity: Input signal sensitivity — controls how hard you must pick to open the filter. Lower values suit quieter pickups. (Low to High). Q: Filter resonance width. High Q produces an exaggerated, dramatic wah; low Q produces a wider, smoother sweep. (Broad to Sharp). Mode: Filter mode: LP (low-pass, bass-heavy), BP (band-pass, mid-wah), HP (high-pass, treble-heavy). (LP to HP)
Envelope filters are extremely sensitive to guitar volume. Running a compressor before the Q-Tron+ standardises pick attack level, making the filter open consistently. A compressor after the filter smoothes out the volume jump when the filter opens dramatically. The effects loop insert on the Q-Tron+ accepts any effect into the filter feedback path. A subtle digital delay in the loop (70ms, 1 repeat) adds a rhythmic echo that reinforces the groove character of the filter. Sensitivity should be matched to pickup output — high-output humbuckers generally need a lower Sensitivity setting than single coils to avoid the filter opening on every note regardless of playing dynamics. Mode selection (LP, BP, HP) is a bigger tonal decision than Q or Sensitivity — settle on the mode for a given part first, then fine-tune Q and Sensitivity within that mode rather than adjusting all three at once. For the most dynamic, expressive funk playing, practice varying pick attack deliberately rather than setting Sensitivity once and playing at constant force — the filter dynamic range is the actual expressive tool, not a fixed EQ curve.
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