The Mr. Black BB-74x is an analog overdrive pedal from Mr. Black, an original Jack Deville design that aims to put the character of a classic British 18W combo amp on a pedalboard. Mr. Black describes it as a responsive circuit emulating that amp, with "All the juice, sag, response and harmonic magic of that legendary 18W EL-84 combo, captured and reformed into one damned sweet little overdrive pedal."1 Pedal of the Day, reviewing it in June 2019, noted that "The BB-74x is based on the Marshall 1974x 18W amp" and called it "this original Jack Deville design."2
Power and connections
The BB-74x runs on 9VDC through a 2.1mm negative center-pin connector and draws 5mA, so any standard 9V pedal supply handles it easily. It can alternatively run on an internal 9V battery, though the battery is not included.1
Mr. Black's product page states "ALL SALES FINAL! NO RETURNS/EXCHANGES/REFUNDS," so purchases of the BB-74x cannot be returned or exchanged.1
Design and what it does
The pedal is a 100% pure-analog overdrive, with no digital circuitry, and it is true bypass, so the circuit is out of the signal path when switched off. Mr. Black's stated aim is to capture the response of the 18W EL-84 combo, an amp prized for the way it breaks up, and reform it as a pedal.1 The circuit's basis in the Marshall 1974x 18W amp is what gives the pedal its Blues Breaker association in reviews.2
The specifications Mr. Black publishes for the pedal are:
| Specification | Value |
|---|---|
| Circuit | 100% pure-analog organic overdrive1 |
| Bypass | True bypass1 |
| Power | 9VDC 2.1mm negative center-pin adapter or internal 9V battery (not included)1 |
| Current draw | 5mA1 |
| Input impedance | ~495K ohms1 |
| Output impedance | <25K ohms1 |
| Enclosure | CNC-milled genuine Hammond enclosure1 |
For players comparing overdrives, the BB-74x sits in the amp-like overdrive territory rather than the mid-humped boost territory of pedals like the Tube Screamer, a difference explored in Boss SD-1 vs Ibanez TS9 Tube Screamer. Mr. Black's wider range of original-design drives includes the Mr Black OD-503, the Mr. Black Black LTD. Power Drive and the Mr. Black Black LTD. Classic 88, alongside the budget Mr. Black JDS-50. More on the type as a whole is on the Overdrive Pedals page.
Price
The BB-74x lists at $199.95 USD as of 26 October 2026, with a sale price of $139.95 shown on the maker's page at the same date.1
Videos
Everyday Guitarist
Pedal of the Day
Dabs of Goo
Questions
Does the Mr. Black BB-74x take a battery?
Yes. The BB-74x can run on an internal 9V battery, but the battery is not included, so you have to supply your own. It can also be powered from a 9VDC 2.1mm negative center-pin adapter, which draws 5mA, well within what any standard pedal supply provides.
Is the BB-74x true bypass?
Yes. Mr. Black lists the BB-74x as true bypass, so when the pedal is off, your guitar's signal passes through without the circuit loading it.
Is the BB-74x analog?
Yes. Mr. Black describes the BB-74x as a 100% pure-analog organic overdrive. There is no digital processing in the signal path.
Who designed the Mr. Black BB-74x?
The BB-74x is an original Jack Deville design, as stated on Mr. Black's product page and echoed in Pedal of the Day's 2019 review of the pedal.
Can the BB-74x be returned?
No. Mr. Black's product page states that all sales are final, with no returns, exchanges or refunds, so it is worth being sure before ordering.
What is the BB-74x's input impedance?
Mr. Black lists the input impedance at approximately 495K ohms, with an output impedance of less than 25K ohms.
Sources (2)
- BB-74x - Mr. Black, Mr. Black
- Mr. Black Pedals BB-74x Blues Breaker Overdrive, Pedal of the Day, 2019-06-26
