Boost1978· MXR (USA)
MXR Micro Amp
Single-knob op-amp clean boost — up to +26 dB of see-through gain.
⏳
Schematic pending verification
We don't ship reference schematics until they've been hand-authored against authoritative sources (manufacturer service docs, ElectroSmash analyses, GEOFEX writeups) and reviewed in the simulator. Until then, the BOM, signal chain, controls and mod notes below are accurate, and you can still add this pedal to a project — it just won't include a circuit yet.
About
A textbook non-inverting op-amp gain stage with a single Gain pot setting the feedback ratio. No tone shaping, no clipping — just clean level on tap. Indispensable for pushing a tube amp or hitting the front of another dirt pedal harder.
Signal chain preview
3 stagesInput
Input AC-coupling cap → high-impedance bias network
TL071 non-inverting op-amp (gain = 1 + RF/RG, RF = Gain pot)
Output cap → output
Output
Quick facts
- Maxes out around +26 dB — enough to slam any front end.
- Slight high-frequency emphasis from the small input cap; some builders swap to 0.1 µF for a flatter response.
- Used as an always-on solo boost by everyone from John Mayer to David Gilmour at various points.
Controls
- Gain (1M linear pot)