
Vintage Bass Octave
M280
The MXR Vintage Bass Octave upgrades the warm
analog sub-bass vibes of a classic circuit with superior
tracking, cleaner headroom, and the versatility that
modern players demand. This pedal delivers an
impressive range of smooth, musical sounds—from a
tone-thickening growl to chest-rumbling dub tones—all
in the lightweight, space-saving MXR mini housing.
jimdunlop.com/m280

External Controls
2
1
4
1 OCT 1 knob controls volume of one-octave
down signal
2 DRY knob controls volume of clean signal
3 OCT 2 knob controls volume of two-octaves
down signal
4 MID switch boosts midrange by up to +13dB
as set by internal TRIMPOT
5 FOOTSWITCH toggles effect on/bypass
(blue LED indicates on)
3
6
5
Internal Controls
6 TRIMPOT adjusts level of midrange boost
engaged by MID switch up to +13dB
MXR | Vintage Bass Octave 2

Basic Operation
Power
The Vintage Bass Octave is powered by the included
Dunlop ECB003 9-volt adapter or the DC Brick™,
Iso-Brick™, and Mini Iso-Brick™ power supplies. This
pedal can not be powered by a battery.
Directions
Run a cable from your guitar to the M280’s INPUT
jack and run another cable from the M280’s OUTPUT
jack to your amplifier.
Start with all controls at 12 o’clock.
Turn the effect on by depressing the footswitch.
Rotate DRY knob clockwise to increase level of dry
signal or counterclockwise to decrease it.
Rotate the OCT 1 knob clockwise to increase level
of one-octave-down signal or counterclockwise to
decrease it.
Rotate the OCT 2 knob clockwise to increase level
of two-octaves-down signal or counterclockwise to
decrease it.
Depress MID switch to boost midrange.
To adjust level of midrange boost engaged by MID
switch, remove bottom plate. Use a trimpot adjustment
tool to rotate internal TRIMPOT clockwise to increase
boost—up to +13dB—or counterclockwise to
decrease it.
MXR | Vintage Bass Octave 3

Specifications
Input Impedance
Bypass
Signal to Noise
Output Impedance
Trigger Threshold
Dry Gain
Octave Gain 1
Octave Gain 2
Mid Switch * 400 Hz or 800 Hz @ 6 dB
Power Requirements 9 VDC @ 45 mA
* Internal switch gain see @ factory with RP1
1M Ω
THW BP
A weighted (Vref IV RMS) - 93 dBV
<1KOhm
-74 dBv @100Hz
-∞ 7dB
-∞ 1.6 dB @ 150Hz in
-∞ 1.7 dB @ 150Hz in
MXR | Vintage Bass Octave 4