MXR M133 Micro Amp
When you need a little boost.
The MXR M-133 Micro Amplifier Pedal adds a preset amount of gain, using a single control. With a guitar, this lets you boost your signal for lead work, adjust between 2 different guitars with unmatched output (i.e.... read more
159 Artists use this
Found 0 artists

This photo of Jack White's pedalboard shows he uses the MXR M-133 Micro Amp (top right of the board). He has also placed an MXR M-133... more

Used with Foo Fighters "around the time of the second album", as stated by guitar tech Earnie Bailey in this August 21, 2017 Effects Bay ... more

A mainstay on John Frusciante's pedalboard, his MXR M-133 Micro Amp Pedal can be seen in the bottom row of this pedalboard from circa 200... more

This photo of Arctic Monkeys guitarist/singer Alex Turner's pedalboard shows he uses the MXR M-133 Micro Amp Pedal. The Micro Amp can be ... more
Reviews
Trusted musician and artist reviews for MXR M133 Micro Amp
Based on 39 Reviews

Best clean boost I've found so far!
If you need a clean boost for solos, this is the one to buy! Unless you feel the need to have some tone sculpting as well to make your leads cut a little more and want to buy the Micro Amp+, this is perfect!
Having the single, big dial makes for easy on-stage adjustments if you find it's not quite the right volume in the moment.
As with all MXR pedals, very sturdy and reliable.


Clean Boost
Very clean boost that doesn't colour the tone of my sound at all. Very useful for pushing through the band when volume is maxed out on my guitar and I need that little bit more volume.

What a great pedal!!!
Smooth, warm, and easy to use. Very helpful to give a punch in the mix to the guitar. Also if you're playing a solo it gives you a little bit of volume without adding gain, in case you put it after the gain pedals. If you put it before, this pedal makes you raise the gain of the pedal in the level you need. Also, it gonna makes you gain a lot of bit of punch in a tube amp. Simply a really great boost pedal.

Bring your tone a little shine like a car wax
I got this pedal inspired by the equipboard of Caleb Followill from Kings of Leon, but also this site recommends this pedal. After testing the MXR Micro Amp with my pedalboard, I found that this pedal brings a little shine to the tone, so your sound will have a proper clarity. After the 12 o'clock, the MXR Micro Amp begins to bring overdrive from the amp, as the volume climbs up. At full range, you obtain a tough overdrive. The dynamics in this pedal are awesome, it improves my playing a lot.

I should talk more about this pedal, which I feel it is glorious to me. It improves the frequencies from the amp, so the clarity obtained let you to low the volumen knob from your guitar without losing dynamics. This is great!


Top quality
It's just amazing. It's built like a tank and it doesn't saturate the signal. It's quite expensive to only feature one knob, but it's more than enough and it's totally worth the price.

Looking for a good all around clean boost well you're in the right ballpark
If you're looking for a clean boost in sound for just a little extra oomph then this could be a pedal for you its sturdy and does the job, but coming from mxr that would be just selling them short on their good quality products, now is it the most amazing pedal well for me no but that is not for me to decide but for you to go out and try it for yourself. I gave this a 4/5 because its a good pedal but nothing to really be blown away by its just a simple little pedal to do one thing and do it pretty well
6
Community Gear Photos
4 Videos Uploaded




Details
Description
When you need a little boost.
The MXR M-133 Micro Amplifier Pedal adds a preset amount of gain, using a single control. With a guitar, this lets you boost your signal for lead work, adjust between 2 different guitars with unmatched output (i.e., humbucker to single coils), or it can supply a permanent boost in a long effects chain where signal drop-off is a problem. Power: Single 9-volt battery or Dunlop ECB-003 AC Adapter - Controls: Footswitch toggles amp on/bypass (red LED indicates on) Gain knob adjusts total output volume when the Micro Amp is engaged.
Very Good When Used as a Clean Boost Pedal
It's worth noting that the Micro Amp is mainly useful in the context of playing live, specifically with a tube amplifier. It's not likely to add much to your solo practice or writing sessions (although if you practice or write at a fairly loud volume, you may find that stomping on this guy when you arrive at a song's solo section fattens your sound a lot, which can be very inspiring) and when used in conjunction with a solid state or hybrid amp, you're unlikely to really be able to take advantage of the M-133's ability to add searing gain to an already-saturated amp sound.
Therefore, please bear in mind that "live performance" is the perspective from which the rest of this review is written, as I have never bothered to use this pedal in a recording context--since two different guitar signals recorded on different tracks can be blended to taste during mixdown, with levels raised or lowered accordingly.
MXR/Dunlop initially marketed the Micro Amp as a mere volume boost, and it definitely does a great job as such. As mentioned earlier, activating on the pedal as you play introduces a boost that is as subtle or extreme as you want it to be; as an added bonus, I can attest that I've never noticed any coloration to my guitar tone when using the M-133. Other boost pedals often introduce a midrange "hump" that I, personally, usually don't mind. But it's nice to know I can use the MXR unit to get more of my sound, unadulterated.
A secondary function, per the manufacturer, is to slam the front end of a tube amplifier with extra volume to create even more saturated gain sounds than an amp is capable of producing on its own. Again, the M-133 Micro Amp excels at this, too.
Recently, MXR/Dunlop has been touting the pedal as a quick fix for guitarists who switch back and forth between, say, a Fender Stratocaster and a Gibson Les Paul during the course of a performance. Anyone who has utilized two instruments with different pickup configurations during the course of a single show is going to be... Read More
You left out the studio. If, like me, you often like to play solos on a vintage spec strat or tele into a an old-school tube amp with moderate amounts of preamp gain, a clean boost like this is an invaluable tool while recording. I used to be a dyed in the wool TS9 man (and later an 80s SD1 guy), often using them as a colored, dirty boost for solos with fender guitars (like everyone and their mother likes to), but in the 90s I got turned on to clean boosts, treble boosts and even the venerable MXR Dynacomp as ways to add gain and 'cut' (these pedals generally turn your hi-z guitar signal into a fairly low-z affair that drives the cable a lot easier which will add/preserve treble just like a buffer) for a solo sound without sacrificing the bandwidth and signature voice of my guitar. I do this more in the studio than live, believe it or not. Live I tend to dime an AC30 and control everything with my guitar volume knob. Maybe I'll run an always-on boost or buffer if I need a line-driver on a big stage.
As far as MXR's claim that this is an easy output matching fix for guys who go between fender and Gibson? The very different frequency responses on bolts with single versus gibbies with buckers means the perceived level may never really match up, but if you're just trying to get them to tickle V1 in your amp similarly it may help. Personally I switch guitars as much for a change in output as I do for a change in feel. I have less need for multiple amps or channel switchers if I recognize that my wannabe-59 tele is not a hard rocker and I save that guitar for ballads and such where a clean, chimey tone and a little less volume at 10 is quite alright... by the same token I have to recognize my 335 mostly wants to rock, but the A2 pickups are soft in tone, low output for humbuckers and sit back in the mix as a rhythm instrument, so I should use her that way live... Then there's my SG. Not a tone of output on paper, but DCR is not the be-all-end-all of output and out-front-ness, because that guitar wants to rock hard and stand out with the vocal as something the audience (when there is one) wants, no.... NEEDS to listen to. And that's just my 3 favorite guitars, they all have a voice and a use which is why MXR's whole marketing conception seems to defeat the point of switching guitars live... or switching at all. Out put and frequency response are 50% of my motivation. a variety of outputs isn't a problem to solve, its a palette of colors to paint with and your tube amp's the brush.
That said, the M-133 is a pretty flat sounding transistorized boost pedal, though it doesn't have the tubey sparkle of a ZVex SHO or any other jfet or mosfet based booster.
Wow. I wish I could add your thoughts to my review as a third-party opinion. That's super valuable input! I haven't really used mine in a studio setting--seemed a little redundant to me, in my admittedly limited experience--so that's very useful information.
I don't really know that MXR is still marketing the MicroAmp as a single-coil/HB matching device, but they sure were about ten years ago when I got mine. Which is odd, given that Seymour Duncan makes a similar device that isn't just a boost pedal, but actually has a bit more going on under the hood. (Like you, though, I'd debate the merits of such a device on grounds that I don't see much point in trying to make different guitars sound the same.)
Thanks for adding those thoughts. I hope anyone who reads my review will also consider your experience as well.
Thanks. I always try to kick out a lot of practical info on pieces of gear I've made extensive use of...