The Mr Black Boost Tiger is a clean boost pedal from Mr. Black. Guitar FX Layouts, the stripboard layout blog, described it as roaring out over +20dB of powerful, clean boost, saying it "breathes life, vigor and super-tiger-powers into" a player's tone1. The circuit is a non-inverting gain stage with the boost pot varying the resistance in the feedback loop, without clipping diodes, and the layout was verified working by multiple builders in the comments1.
How the circuit works
The Boost Tiger uses a two-opamp design. Guitar FX Layouts explains that one opamp channel is the boost circuit while the other provides the half supply reference voltage. The booster itself is a non-inverting gain stage with the boost pot varying the resistance in the feedback loop, and it runs without clipping diodes1.
That last point is what sets it apart from the overdrives it resembles. The blog notes the topology is like many other pedals, such as Tube Screamers, but without the clipping diodes to keep it cleaner1. A Tube Screamer uses its diodes to clip the signal and, as anasounds.com puts it, deliver "a nice boost in the mids to get the guitar over the mix"3. Remove the diodes and the same gain stage simply amplifies: the Boost Tiger passes the guitar's own character through at higher level rather than adding overdrive of its own.
"Roaring out over +20dB of powerful, clean tiger-boost, the Boost Tiger breathes life, vigor and super-tiger-powers into"
Bypass switching
For anyone building the circuit, bypass is a design choice rather than a fixed feature. Guitar FX Layouts states that it depends what method of bypass you choose to use, and that the circuit could be used with true or buffered bypass switching1. The blog's layout was verified working by multiple builders in the comments after publication in March 20131.
The circuit today: the Black Tiger Boost
Although the pedal itself is discontinued, the circuit is still available to DIY builders. PedalPCB.com sells the Black Tiger Boost, a DIY pedal PCB it lists as a comparison to the Mr Black Boost Tiger4. The board carries a single Boost knob that controls the amount of boost as of October 20264.
The original Boost Tiger pedal was discontinued by 20152. The Black Tiger Boost from PedalPCB is an unaffiliated DIY board for building the circuit yourself, not a Mr. Black product4.
Videos
Curtis Kent
Rhion Thomas
Rob Russell
Questions
Does the Mr Black Boost Tiger clip or distort?
No. The circuit uses the same non-inverting gain stage with a boost pot in the feedback loop that you find in many overdrives, but it leaves out the clipping diodes entirely. Guitar FX Layouts, which published the layout, describes the result as a powerful, clean boost of over +20dB. Where a Tube Screamer uses its diodes to shape the signal into overdrive, the Boost Tiger simply amplifies whatever you feed it, so your amp and pickups set the character of the sound.
How is the Boost Tiger different from a Tube Screamer?
The two share a similar non-inverting feedback-loop boost topology, but the Tube Screamer includes clipping diodes that compress and color the signal, giving what anasounds.com calls a nice boost in the mids to get the guitar over the mix. The Boost Tiger omits those diodes to keep the signal cleaner, so it boosts without the mid hump and soft clipping associated with the Tube Screamer sound.
Can the Boost Tiger be built with true bypass?
Yes, depending on the switching method chosen. Guitar FX Layouts notes that the circuit could be used with true or buffered bypass switching, so a builder decides which approach to take when wiring the footswitch. The published stripboard layout was verified working by multiple builders in the comments on the blog.
Is the Mr. Black Boost Tiger discontinued?
Yes. In a 2015 Strymon pedalboard feature, guitarist Dave Depper described the Boost Tiger as his favorite transparent boost, made in Portland, and noted that it was sadly discontinued. The circuit remains available to DIY builders through the PedalPCB Black Tiger Boost board, which the company lists as a comparison to the Mr Black Boost Tiger.
Who provided the Boost Tiger schematic?
Jack Deville provided the schematic for revision B1 of the circuit. Guitar FX Layouts published its stripboard layout of the Boost Tiger in March 2013, describing it as a new version, revision B1, built from the schematic Deville supplied.
What is the Black Tiger Boost?
The Black Tiger Boost is a DIY pedal PCB sold by PedalPCB.com. It is a boost circuit that PedalPCB lists as a comparison to the Mr Black Boost Tiger, with a single Boost knob that controls the amount of boost.
Sources (4)
- Guitar FX Layouts: Mr Black Boost Tiger, Guitar FX Layouts (tagboardeffects.blogspot.com), 2013-03-11
- Pedalboard Feature: Dave Depper, Strymon, 2015-10-05
- OD/Disto/Fuzz : The key differences between these 3 effect pedals, anasounds.com, 2019-04-04
- Black Tiger Boost, PedalPCB.com
