Dunlop M89-U
Dunlop M89-U
Dunlop M89-U
Dunlop M89-U
Dunlop M89-U
Dunlop M89-U
Dunlop M89-U MXR Bass Overdrive Pedal
Product images are provided for reference and may not represent the exact model, configuration, or included components.

At A Glance

Input Impedance
1 MΩ
Output Impedance
Signal To Noise
>95 dB
Current Draw
19 mA
Power Supply
9 volts DC
Description

Dunlop positioned the MXR M89-U Bass Overdrive as a dedicated bass effects pedal designed to deliver overdriven tones while preserving low-end integrity. It sat within the MXR effects line as a bass-specific drive unit.

The M89-U operated on a 9-volt DC power supply, drawing 19 mA of current. It offered an input impedance of 1 MΩ and an output impedance of under 10 kΩ, with a signal-to-noise ratio exceeding 95 dB. A Clean control allowed the player to blend in a pre-set EQ clean signal alongside the overdriven signal, giving direct control over the balance between clean and driven content.

Owners sourcing a replacement power supply should confirm 9-volt DC centre-negative compatibility before substituting. For any internal servicing or component-level work, a qualified guitar technician or electronics repair professional is the appropriate resource.

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