The JAM Pedals "Mid Air" Boomster mk.2 is three pedals in one enclosure: a buffer, a clean booster and a volume pedal. The Level control provides up to 16 dB of clean boost, the internal OPA2132 circuit can be left always-on as a buffer, and a standard passive expression pedal can be connected to sweep the pedal's volume with your foot. JAM describes each of its pedals as crafted with care, and custom artwork versions are one-of-a-kind hand-painted pieces, so the pedal received differs in detail from photos shown1.
Three voicings and internal settings
The Boomster mk.2 offers three voicings, each shaping the boosted signal differently1:
| Voicing | What it does | Adjustment |
|---|---|---|
| High-cut | Attenuates the top end | Amount set with an internal trimmer |
| Full-range | Keeps the response flat and open | None needed |
| Mid-boost | Adds focused midrange | Amount set with a second internal trimmer |
The two trimmers are internal, so setting the amount of high-cut or mid-boost means opening the pedal up rather than turning a top-panel knob. For a player, that keeps the outside of the pedal simple: pick a voicing, set the trimmer once to taste, and use the Level control from the top panel from then on1.
Buffer, bypass and the expression input
In buffered mode, JAM says the OPA2132 circuit restores frequencies lost through long cable and pedal runs without adding brittle highs or changing the instrument's feel1. Internal DIP switches select true or buffered bypass, so the pedal can sit on a board as a permanent line driver with the buffer always in the circuit, or behave like a conventional true-bypass boost when switched on1.
The expression input takes a standard passive 10 kΩ expression pedal, which turns the Boomster mk.2 into a traveling volume pedal1. If you plan to use that function, you will need an expression pedal of your own; it is not included.
The footswitch supports both momentary and latching operation, so the pedal can be tapped on and off in the usual way or held down for as long as the effect is wanted1.
Power, size and buying notes
The pedal runs on 9 to 18V DC, center-negative, and JAM recommends an isolated supply1. It draws a maximum of 50 mA1. Physically it measures 7.5 x 12 x 5.6 cm (2.9 x 4.7 x 2.2 in) including jacks and controls, and weighs 300 g (0.66 lb)1.
JAM lists the regular price at £294.00 GBP, tax included, as of 25 October 20261. The maker also offers a 30-day money-back guarantee with a refund, no questions asked, if you are not satisfied after receiving the product1. JAM also makes an "Achenbach" version of the Boomster mk.2, listed separately as the JAM Pedals "Achenbach" Boomster mk.2, and the original JAM Boomster Mk2 is covered on its own page.
If you are comparing this pedal with simpler units, the Buffer Pedals page gathers dedicated buffers such as the Empress Effects Buffer and TC Electronic Bonafide Buffer, while the Boost Pedals and Volume Pedals pages cover the other two jobs the Boomster mk.2 combines.
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Questions
How much boost does the Boomster mk.2 give?
The Level control provides up to 16 dB of clean boost, according to JAM Pedals. The boost is described as clean, meaning it raises your signal's level without adding distortion of its own, and the three voicings (High-cut, Full-range and Mid-boost) shape which part of the frequency range gets emphasized as you raise the level.
Can the Boomster mk.2 be true bypass?
Yes. Internal DIP switches let you select either true bypass or buffered bypass. In buffered mode, the pedal's OPA2132 circuit restores frequencies lost through long cable and pedal runs, which JAM says it does without adding brittle highs or changing the instrument's feel. You can set the pedal to whichever bypass style suits your rig.
Can I use an expression pedal with the Boomster mk.2?
Yes. The pedal accepts a standard passive 10 kΩ expression pedal, which lets you use the Boomster mk.2 as a travelling volume pedal, sweeping your level with your foot while the boost and voicing controls stay where you set them.
What power supply does the Boomster mk.2 need?
The pedal runs on 9 to 18V DC, centre-negative, and JAM recommends an isolated supply. It draws a maximum of 50 mA. Because the pedal accepts up to 18V, check your supply's output voltage before plugging in, and avoid daisy-chaining it with digital pedals unless your supply is isolated.
How much current does the Boomster mk.2 draw?
JAM Pedals lists the maximum current draw at 50 mA. That is modest by pedal standards, but the maker recommends an isolated power supply, so a dedicated output on your pedalboard power supply is the suggested way to power it.
Does the Boomster mk.2 have momentary footswitch operation?
Yes. The footswitch supports both momentary and latching operation, so you can either hold the switch down for as long as you want the effect engaged or press and release it to toggle the pedal on and off, depending on how you prefer to play.
Sources (1)
- “Mid Air” Boomster mk.2, JAM Pedals (www.jampedals.com)
