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ME-20B: Bass Multiple Effects

Performance-Based Effects for Bass


The second new offering in the ME series is the ME-20B, a powerful multi-effects unit optimized for live performance. With the same performance-based design as its guitar-focused ME-20 counterpart, the ME-20B is aimed at the performing bassist who wants stage-friendly effects and solid construction at an affordable price. Mix, match, and customize a wide variety of effects, including compressor, overdrive, distortion, T-Wah, phaser, flanger, chorus, delay, reverb, defretter, synth, and more.

  • Performance-based bass processor for the player who wants an easy-to-use interface with BOSS tone and quality
  • New super-tough metal chassis with 3 footswitches, 5 realtime control knobs, and expression pedal
  • EZ Edit for quick sound creation
  • Unique effects such as Synth, Octave, Defretter, and more
  • BASS ENHANCE function for instant presence boost
  • 30 user memory locations in addition to realtime operation
  • Battery or AC powered

Performance-Based Effects for Bass

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Simple Operation — Works Like Compact-Pedal Effects

To get the sound you want, simply select an effect and tweak it using the knobs. It’s the same simple operation offered by compact-pedal effects. Special attention has been given to ease of operation and speed of use — ideal for immediate editing on stage or in the studio.

FX for Bassists

Mix, match, and customize a wide variety of effects for bass, including compressor, overdrive, distortion, T-Wah, phaser, flanger, chorus, delay, reverb, defretter, synth, and more.


This function strengthens bass dynamics with a simple button press, adding richness and impact to the tone. You can also activate the effect with an optional pedal — great for instantly activating a "bass solo" tone.

EZ EDIT for Quick Sound Creation

EZ EDIT lets you create sounds quickly and intuitively, with incredible ease and speed like no other multi-effects unit on the market. You can adjust a combination of effect parameters with a single knob, and then save your creations for instant recall.

Memory Function

Up to 30 of the sounds you create can be stored in the ME-20B’s User memory. In Memory mode, you can use the pedals to instantly select a stored sound. Since the ME-20B makes it so easy to create new sounds, the user memory bank ensures that you’ll never lose those perfect patches.


Plug a CD or MP3 player into this input jack and jam along with your favorite music. It’s also a great way to plug in and play along with your favorite bass heroes to help build and strength your chops.

Battery Powered Operation

The ME-20B runs on battery power (six AA dry cells) so you can use it anywhere. You can also use the optional AC adaptor for extended performances. Wherever you travel, the ME-20B goes with you and never requires an additional AC outlet. For those who want to plug in, however, an optional AC adaptor can be used.

Performance-Based Effects for Bass


AD Conversion
24-bit + AF method (*)
DA Conversion
Sampling Frequency
44.1 kHz
30 (user)
Nominal Input Level
INPUT: -10 dBu, AUX IN: -18 dBu
Input Impedance
INPUT: 1 M ohm, AUX IN: 22 k ohms
Nominal Output Level
-10 dBu
Output Impedance
2 k ohms
7 segments, 2 characters LED
SFX/1 pedal, COMP/2 pedal, DELAY/3 pedal, Expression pedal
INPUT jack (1/4 inch phone type), AUX IN jack (Stereo miniature phone type), OUTPUT jacks L/MONO, R (1/4 inch phone type), PHONES jack (Stereo 1/4 inch phone type), FOOT SW jack (1/4 inch TRS phone type), AC Adaptor jack
Power Supply
DC 9 V: Dry battery LR6/R6 (AA) type x 6, AC Adaptor (PSA series: Optional)
Current Draw
90 mA * Expected battery life under continuous use: Alkaline: 13 hours, Carbon: 3.5 hours (These figures will vary depending on the actual conditions of use.)
Owner's Manual, Dry battery LR6 (AA) type (alkaline) x 6, Roland Service (Information Sheet)
AC Adaptor: PSA series, Footswitch: FS-5U, Dual Footswitch: FS-6, FS-7, Connection Cable: Roland PCS-31 (Stereo 1/4 inch phone plug - 1/4 inch phone plug x 2)
Size and Weight
294 mm
11-5/8 inches
179 mm
7-1/16 inches
54 mm
2-1/8 inches
1.6 kg
3 lbs. 9 oz.
(*) AF method (Adaptive Focus method) This is a proprietary method from Roland that vastly improves the signal-to-noise (S/N) ratio of the A/D and D/A converters
*The specifications are subject to change without notice.



Dual Footswitch


Two switches in one, BOSS’s FS-6 combines latch- and momentary-type switching into one unit.

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Dual Footswitch


Compact, multifunctional dual footswitch for remote control of effect pedals or amp channel switching.

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If you have questions about operating your Roland, BOSS or Cakewalk product, please check our Knowledge Base for answers to the most common questions.

You can also contact our Product Support department by phone or email.

In addition, we have a library of Support Documents that you can download and reference. If Support Documents are available for this product, they will be listed below.

Support Documents

BOSS Product Catalog 2008
Forging the Future - Innovation for Creative Inspiration
BOSS forges into 2008 with an awe-inspiring lineup of effects, digital studios, and accessories.
BOSS Guitar Effects Guidebook
BOSS offers an extensive selection of guitar effects that can be used by guitarists to get any kind of sound you can imagine. Here's a quick reference guide to the type and function of each unit.
ME-20B TurboStart
ME-20 & ME-20B Brochure
BOSS Product Catalog 2014
BOSS Product Catalog 2012
BOSS Product Catalog 2011

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