Detail 01
Sweepable midrange: 250 Hz–1 kHz
The mid control can be positioned within that range rather than fixed at one frequency.
Product detailSKU #1393862857645
MXRM81 Bass Preamp
Independent shopping perspective
The Korena take
MXR’s M81 puts bass preamp control and a Direct Out into a compact pedalboard format. Separate input and output controls let you manage gain staging, while the three-band EQ adds a sweepable 250 Hz–1 kHz midrange control for targeted shaping. The Direct Out can be sent before or after the pedal EQ, and a Ground Lift switch is available for ground-loop hum. Internal switches also let a ¼-inch-only rig change to true bypass.
Strong match
Who this is for
- Bass pedalboards needing EQ control and a Direct Out in limited space.
- Sending bass directly to the house with a choice of pre- or post-EQ signal.
- Fine-tuning midrange between 250 Hz and 1 kHz during rehearsal or performance.
Consider the trade-offs
When to look elsewhere
- A ¼-inch-only setup unless you are prepared to use the internal switches for true bypass.
What matters in use
The specifications, translated
Catalog numbers tell only part of the story. These are the details most likely to change how this product feels, sounds, or fits into a setup.
Detail 02
PRE/POST EQ Direct Out switch
It chooses whether the Direct Out receives the pedal’s EQ treatment.
Detail 03
Ground Lift switch
It is provided for situations involving ground-loop hum.
Detail 04
Internal bypass switches
They can disable the Direct Out and buffered ¼-inch bypass for true ¼-inch bypass mode.
Final check
Know before you order
- 01Out of the box, the ¼-inch output uses buffered bypass and the Direct Out is active.
- 02True ¼-inch bypass requires changing two internal switches.
Product questions
Before you decide
Straight answers to the questions shoppers most often ask about this product.
01Can the Direct Out bypass the EQ?
Yes. The PRE/POST EQ switch lets you choose whether the Direct Out is affected by the pedal’s EQ.
02What is the default output configuration?
It leaves the Direct Out active and sets the ¼-inch output to buffered bypass.
03Can I use only the ¼-inch output in true bypass?
Yes. Two internal switches disable the Direct Out and buffered bypass for true ¼-inch bypass mode.
