BOSS ME-50 Guitar Multiple Effects Owner's Manual

Simple Operation: Works Like a Compact Effects Processor

Each effect is controlled by a dedicated knob, offering intuitive operation similar to compact effects processors, allowing direct tone adjustments.

Powerful COSM Drive Sound

Utilizing Roland's original “COSM” modeling technology, the ME-50 provides a wide array of distortion effects, ranging from classic vintage tones to original distortion sounds.

COSM (Composite Object Sound Modeling): COSM is Roland's innovative sound modeling technology. It analyzes the electrical and physical characteristics of original sounds to create digital models that accurately reproduce them.

Multi-Function Expression Pedal

The ME-50 features an expression pedal that allows control over six specialized pedal effects. It can also be switched to function as a volume pedal.

Memory Function

Store up to 30 custom-created tones (Patches). These can be instantly recalled using the pedals in “Memory mode.”

AUX IN Jack

The AUX IN jack facilitates practice sessions by allowing connection to external audio sources like CDs or MDs.

Battery-Powered Operation

The ME-50 can be powered by six AA batteries or an optional AC adaptor.

About the Effect Connection Sequence

The ME-50 automatically optimizes the effect connection sequence based on the selected effect. For example, when WAH, RING MOD, +1OCTAVE, or -1OCTAVE is selected, the signal path is TONE MODIFY → EXPRESSION → COMPRESSOR → OVERDRIVE/DISTORTION → NS → VOLUME (PEDAL) → MODULATION → DELAY → REVERB. When RESONANCE and VOICE are selected, the path is TONE MODIFY → COMPRESSOR → OVERDRIVE/DISTORTION → EXPRESSION → NS → VOLUME (PEDAL) → MODULATION → DELAY → REVERB. For MODULATION types like TREMOLO or UNI-V, MODULATION precedes OVERDRIVE/DISTORTION.

TONE MODIFY

This effect alters the characteristics of the connected guitar. The TYPE knob offers several settings:

• OFF: Bypasses the sound. The TONE MODIFY indicator turns off.
• FAT: Provides a fat tone with boosted mid-range.
• PRESENCE: Offers a bright tone with boosted high-mid range.
• MILD: Creates a mild tone with reduced high end.
• TIGHT: Adjusts tone by cutting low frequencies.
• ENHANCE: Boosts high frequencies.
• S↔H: Switches between single-coil and humbucking pickup tones.
• H↔S: Switches between humbucking and mixed single-coil pickup tones.
• H↔HF: Switches between humbucking and single-coil pickup half tones.
• HOLLOW: Adds body resonance for an acoustic guitar-like tone.
• ACOUSTIC: Transforms the electric guitar tone into an acoustic guitar tone.

Switching Tone Modify On and Off with the Foot Switch: Connect an optional FS-5U foot switch to the FOOT SW jack to toggle Tone Modify on and off. A special cable (PCS-31) can connect two foot switches for Tone Modify and Compressor control.

COMPRESSOR

This effect provides long sustain by evening out input signal volume levels, and can also function as a limiter to suppress peaks and prevent distortion. The SUSTAIN knob controls the effect depth (longer sustain clockwise, limiter effect counter-clockwise). Turn SUSTAIN to OFF when not using the compressor; the indicator will go out. The LEVEL knob adjusts the volume when the compressor is active, helping to balance levels when switching effects on/off.

Switching the Compressor On and Off with the Foot Switch: Similar to Tone Modify, an FS-5U foot switch connected via a PCS-31 cable can control the Compressor.

OVERDRIVE/DISTORTION

These effects distort the guitar sound. The OD/DS pedal toggles the effect on/off. The DRIVE knob adjusts distortion level, increasing volume and distortion clockwise, with a TURBO range at maximum. The BOTTOM knob shapes the low-frequency range (boosted right, cut left). The TONE knob adjusts the tone (sharper right, milder left). The LEVEL knob adjusts volume, aiming for consistent apparent volume whether the effect is on or off.

The TYPE knob, combined with [VARIATION], offers 22 distortion types, including NATURAL, CRUNCH, LEAD, LOUD, METAL, MODERN OD, STACK, Hi GAIN, MODERN DS, SQUARE, and OCT FUZZ, each modeled after specific classic pedals or sounds.

MODULATION

Modulation effects broaden sound and add undulations. The ME-50 offers 11 types, selectable via the TYPE knob. The MOD pedal toggles the effect on/off. Key controls include RATE/KEY (adjusts modulation rate/speed), DEPTH/HARMONY (adjusts effect depth), and E.LEVEL/RESONANCE (adjusts volume). Effects include CHORUS, STEREO CHORUS 1 & 2, PHASER, FLANGER, HARMONIST (requires specifying song key for pitch-accurate harmonies), TREMOLO (volume modulation), PAN (stereo panning), VIBRATO (pitch modulation), UNI-V (unique undulation), and ROTARY (rotary speaker simulation).

Adding an Effect Synchronized to the Performance Tempo: For most modulation effects (except HARMONIST), tempo can be set by holding the MOD pedal for two seconds, then tapping the pedal in time with the desired tempo. The pedal indicator will flash to show tempo input.

DELAY

The DELAY effect adds delayed sound for depth or special effects. The DELAY pedal toggles the effect on/off. The TYPE knob selects delay types: 0-30 ms, 25-125 ms, 100-500 ms, 400-2000 ms, ANALOG, SLOW ECHO, PAN, SPACE PAN, REVERSE, HOLD, and TAP. Controls include TIME (delay time), FEEDBACK (repeats), and E.LEVEL (delay volume).

Adding a Delay Synchronized to the Performance Tempo: For types other than HOLD and TAP, tempo can be set by holding the DELAY pedal for two seconds, then tapping the pedal in time. For TAP tempo, the DELAY pedal is used to tap the tempo directly.

HOLD Function: Allows recording up to 2 seconds of audio for playback and layering. Press the DELAY pedal to start/stop recording and playback.

NS (Noise Suppressor)

This effect reduces noise and hum picked up by guitar pickups without affecting the natural guitar sound. The THRESHOLD knob adjusts sensitivity to noise levels. Turning it to OFF bypasses the effect.

REVERB

Adds reverberation to the sound. The knob selects between ROOM (small room), HALL (large hall), SPRING (amp spring reverb), and MOD (hall reverb with modulation). The amount of effect is adjusted by knob position.

Pedal

The expression pedal can be set as a VOLUME pedal (indicator off) or an EXPRESSION pedal (indicator on). As an EXPRESSION pedal, it can control effects like WAH, RESONANCE, VOICE, RING MOD, +1 OCTAVE, and -1 OCTAVE. For VOLUME mode, raising the toe decreases volume, and pressing down increases it.

Switching Between Manual and Memory Mode

Manual mode reflects panel settings directly (indicated by a dot in the display). To switch to Memory mode, press pedals 2 and 3 simultaneously; the MEMORY indicator lights up, and the dot disappears. Pressing pedals 2 and 3 again switches back to Manual mode.

Write Procedure

To save created tone settings (knobs, pedals, MASTER LEVEL, expression pedal) to a Patch, use the Write procedure. This can be done in Manual or Memory mode. Unsaved tones are lost when power is turned off or a different Patch is selected.

Calling Up and Using Stored Tones (Patch Change)

Use BANK [ ] [ ] and number pedals (1-3) to switch Patches. Bank 1, Number 1 is the default upon power-on. Pressing a number pedal recalls the corresponding Patch instantly.

Switching Banks

Pressing the BANK [ ] [ ] pedals cycles through banks. Once a bank is selected (indicated by a flashing display), pressing a number pedal (1-3) selects the specific Patch within that bank.

Switching Banks with the Foot Switch

An optional FS-5U foot switch connected to the FOOT SW jack allows bank switching. Using a PCS-31 cable allows both up and down bank switching.

Notes When Using Memory Mode

Tone Changes: Knob adjustments in Memory mode are temporary and lost upon switching Patches or entering Tuner mode, unless saved via the Write procedure. If a knob's position differs from the stored setting, the change takes effect once the knob is moved past the stored value's position. In Memory mode, effects cannot be switched on/off using pedals 1, 2, or 3.

Tempo Setting: Holding a number pedal for two seconds enters tempo setting mode. The unit's behavior depends on DELAY and MODULATION status. If DELAY is ON (and not HOLD/TAP), tap input sets delay time. If MODULATION is ON, RATE can be set for most effects. Tempo settings are temporary.

About the DELAY HOLD

When DELAY is ON and a HOLD Patch is active, the pedal indicator flashes slowly for recording standby. Holding the pedal starts recording, releasing stops recording and starts playback. Continuous pressing allows overdubbing. Rapid pressing releases HOLD and returns to standby.

DELAY TAP

When DELAY is ON and a TAP Patch is active, the pedal indicator flashes, allowing delay time to be set via tap input.

Changing the Patch Settings (Patch Edit mode)

To edit a Patch, switch to it, press [EDIT/EXIT] (MEMORY indicator flashes), adjust knobs/pedals, and then use the Write procedure to save. Pressing [EDIT/EXIT] again without saving returns to Memory mode. Effects like OVERDRIVE/DISTORTION, MODULATION, and DELAY cannot be switched on/off in this mode.

Tuning the Guitar (Tuner)

The ME-50 includes a chromatic auto-tuner that mutes output for silent tuning. Activate Tuner mode by pressing pedals 1 and 2 simultaneously; the TUNER indicator lights up. Play a string, and its closest note appears in the display. The dot in the display indicates sharps (#). Mute other strings for accuracy. Rough tuning aligns the note name, while fine-tuning lights the center (green) indicator. Reference pitch can be adjusted via TUNER PITCH [ ] [ ]. Exiting Tuner mode saves the pitch setting.

Practicing Along with CDs and MDs (AUX IN)

Connect CD/MD players or other devices to the stereo mini AUX IN jack. The input sound mixes with the guitar sound, ideal for headphone practice. Volume for the AUX IN source must be adjusted on the connected device itself. Avoid using cables with resistors, as they can make the audio inaudible.

Returning the ME-50 to Its Factory Settings (Factory Reset)

To restore all settings (patches, tuner reference pitch) to factory defaults, turn off the unit. Then, while holding BANK [ ] and [WRITE], turn the power on. “F” will appear. Press [WRITE] twice to execute the reset. The unit returns to Manual mode.

Adjusting the Expression Pedal

If the expression pedal becomes misaligned, recalibrate it. Turn off the unit. While holding BANK [ ] and [WRITE], turn power on (“P” then “U” appears). Press the pedal heel-down, press [WRITE] (“d” appears). Press the pedal toe-down, press [WRITE] (“5” appears). Adjust the PEDAL MODE SW (1-9) to set sensitivity. Press [WRITE] to save.

Troubleshooting

If there is no sound or the unit functions incorrectly, check connections, volume levels, headphone output, parameter settings, expression pedal position, and Tuner mode status. If patches cannot be changed, verify the unit is not in Manual, Patch Edit, or Tuner mode.

Specifications

The ME-50 features 24-bit AD/DA conversion, a 44.1 kHz sampling frequency, 30 user patches, and various effects including Tone Modify, Compressor, Overdrive/Distortion, Modulation, Delay, Reverb, and Noise Suppressor. It supports expression pedal effects like Wah and Volume. Input/output levels are -10 dBu, with input impedance of 1 MΩ (INPUT) and 100 kΩ (AUX IN). It can be powered by six AA batteries (approx. 12 hours alkaline, 3.5 hours carbon) or a PSA series AC adaptor. Dimensions are 384(W) x 225(D) x 78(H) mm, and weight is 3.15 kg. Accessories include the Owner's Manual and batteries. Options include AC Adaptor and Foot Switch.

Patch List

A table lists 30 factory Patches across 10 Banks, each with a description of its sound, such as “Lead distortion sound with sustain” or “Crunch sound with particularly rough distortion.”

Factory Settings

Detailed tables outline the factory default settings for all parameters across the 30 Patches, covering TONE MODIFY, Expression Pedal, COMPRESSOR, OVERDRIVE/DISTORTION, MODULATION, DELAY, NS, REVERB, and MASTER LEVEL.

Blank Chart

A blank chart is provided for users to record their own custom patch settings.

Index

An index is included to help locate specific topics within the manual.