Design and Tone. Perfected. 

Tone crushing overdrive and super transparent modern sound is the essence of the Microtubes B7K. One of the most acclaimed Darkglass pedals in the bass community, it doesn´t compromise the original sound of the instrument, but it enhances its presence in the mix.

Front Features

Blend

Mixes the clean input signal with the overdriven signal. The clean signal remains at unity gain while the volume of the overdriven signal is set by the Level knob, allowing for fine control of the blend ratio. 

Level

Sets the volume of the overdriven signal. 

Drive

Sets the amount of saturation in the overdriven signal. 

Attack Switch

Sets the amount of treble content to saturate: The “Boost” setting emphasizes the treble content extra clarity and presence.

The “Flat” position leaves this register untouched while the “Cut” position will reduce the amount of high frequencies being saturated.

This new addition helps to keep the treble portion of the signal under control, specially useful when playing with new strings and/or cabinets with tweeters! 

Grunt Switch

Sets the amount of low frequency content to saturate by selecting between three different bass boost levels before the clipping stage. 

Low

+-12dB @ 100Hz 

Low Mids Switch

This switch change the center frequency of the Low Mids from 1kHz to 500Hz. 

Low Mids

+-12dB @ 500Hz 

Hi Mids

+-12dB @ 1.5kHz 

Hi Mids Switch

This switch change the center frequency of the Hi Mids from 3kHz to 1.5kHz. 

Treble

+-12dB @ 5kHz

Input & Outputs

Output

Connect from the ¼” Output jack to the input of your amplifier or another effects pedal. 

Ground Lift

Use this control to lift the ground of the XLR output. If you are experiencing ground noise in your DI signal, try changing this control.

Direct Output

A balanced version of the ¼” output, useful for running into PA’s or studio mixing consoles. 

Input

Connect your instrument or output from your pedal board to the ¼” mono jack.

9V DC

Only use a regulated 9V DC adapter with a center-negative plug.

Parallel Output

A passthrough for your input signal, useful for parallel processing.

• Powerful Tone Sculpting: Combines a preamp, EQ, and overdrive in one, allowing bassists to craft their ideal tone with precision and clarity.
• 4-Band Active EQ: Features bass, low mids, high mids, and treble controls, letting you shape your sound across all frequencies for a wide tonal range.
• Blend Control for Perfect Balance: Mixes clean and distorted signals, retaining low-end punch while adding overdrive, ideal for both subtle warmth and heavy grit.
• Attack and Grunt Switches: Tailor your tone further with Attack for enhanced pick attack and treble and Grunt for low-end saturation and warmth.
• DI Output for Studio & Stage: Includes a built-in DI output, making it easy to connect directly to PA systems or recording equipment without extra gear.
• Analog Drive Engine: The B7K's analog circuitry delivers rich, natural, and responsive overdrive, perfect for rock, metal, and any genre needing punch and depth.
• Compact and Road-Ready: Built to withstand heavy use, this pedal is tour-friendly and designed to fit easily into your pedalboard.

Video Review: Darkglass Electronics Microtubes B7K 2.0 Analog Bass Preamp & Overdrive