The MXR M-181 Bass Blowtorch is an analog bass overdrive pedal that also covers distortion and fuzz territory. MXR describes it as "made to deliver the hottest sounds this side of Hades--from a tube-like growl to full-blown distorted madness." Its overdrive is focused in the midrange frequencies, so you retain your low-end thunder and high end while the overdriven mids cut through the mix1.
What it does
Because the overdrive is centered on the mids, the pedal is built to keep a bass sound intact while letting the distorted part of the signal sit forward in a mix. MusicRadar's review summed it up as "front-end distortion, valve warmth and dry-to-wet blending is easy," and described it as "a highly adjustable bass overdrive/fuzz that caters for all playing styles"2.
The controls
The pedal pairs its drive section with tone-shaping and signal-routing features:
- Blend knob: balances the distortion with the direct signal for the exact tone you're after, so clean low end can sit under the drive1
- Active 3-band EQ with a mid shift switch: provides precise signal balancing1
- Volume: adjusts overall level2
- Thru output: allows input splitting for even more sonic options2
The thru output is worth noting for players with larger rigs: it sends the input signal out separately, which makes splitting the input to a second path possible alongside the distorted signal2.
Power
The Blowtorch runs on an 18-volt circuit, specified as 18V DC, center negative, drawing 9mA12. MusicRadar called it a "powerful 18-volt circuit" in a compact presentation2. An 18V supply is not what every pedalboard power supply offers, so make sure yours has an 18V output before adding it to a board.
What reviewers said
MusicRadar's verdict: "With volume, gain and a decent blend control, this will fatten up your sound as much as you want"2.
Manual
An English manual for the M-181 Bass Blow Torch is available as a PDF at midimanuals.com1.
Videos
basskite
Bryan R Tyler
Jo Bass
Questions
Is the MXR Bass Blowtorch true bypass?
Yes. The pedal uses true bypass circuitry, which means it is really off when you want it off, leaving your signal completely unaffected when the effect is disengaged.
What does the thru output on the Bass Blowtorch do?
The thru output allows input splitting, sending your clean input signal elsewhere while the pedal processes its own path. That opens up more sonic options, such as running a second effect chain or feeding another amp or recording input alongside the distorted signal.
Does the Bass Blowtorch have a blend knob?
Yes. The Blend knob lets you balance the distortion with the direct signal for the exact tone you are after, so you can keep your clean low end underneath the overdriven sound.
Where can I find the Bass Blowtorch manual?
An English manual for the M-181 Bass Blow Torch is available as a PDF hosted by Midi Manuals, linked from the pedal's product documentation.
Sources (2)
- M181 Bass Blow Torch by MXR, RockBoard PedalPedia, 2026
- MXR M-181 Bass Blow Torch review, MusicRadar, 2010-04-12
