MXR M133 Micro Amp

About the MXR M133 Micro Amp

The MXR Micro Amp is a simple one-knob boost pedal. It is a good boost but not perfectly transparent, voiced to add a little colour and start breaking up as you turn it up rather than staying pristinely clean. Owners use it as a volume or solo boost and as an always-on level lift.

In one paragraph

The page's figures as one paragraph, assembled for quoting; not written by hand.

Listings of the MXR M133 Micro Amp we watched from listing to sale typically went in 30 days (23 watched), a steady; it sells for a median of €50 over the last 90 days across 26 recorded sales, with most examples landing between €45 and €50. There are 160 listings live right now across Reverb, from €48 asking, a median ask 88% over the sale median. Figures computed 18 October 2026 by Doirado from cross-platform listing data.

What owners have said elsewhere

Paraphrased from 171 discussion threads among 8 owners, 2024. No names, nothing quoted.

The Micro Amp is a simple, one-knob boost, and owners treat it as exactly that. It is a good boost but not perfectly transparent: at low settings it is fairly clean, and as you turn it up it adds a little colour and starts to break up rather than staying pristine, so if you want a truly transparent lift some point to the more transparent CAE MXR Line Driver. Owners run it as a volume or solo boost and an always-on level lift, it turns up in John Frusciante-style rigs, and it is often weighed against the MXR Dyna Comp as a first pedal. One thing that trips people up: if you boost into an amp channel that is already saturated, you just get more gain, not more volume, because the preamp is out of headroom. The fixes owners suggest are to keep the boost modest (many never push past about 11 o'clock), run it into a relatively clean amp, or put it in the amp's effects loop so it hits the power section and actually gets louder.