HotBox 125i

The HotBox 125i is our top-of-the line, multi-stage, multi-mode inductive power attenuator. The HB125 allows you to enjoy the gloriously sweet overload tones of your valve amp running at eleven, but without hearing damage or police knocking on your door.

This MkV model offers fixed Venue and Studio settings to provide just the perfect amount of reduction whilst being repeatably predictable night-after-night for consistent recording and performance. In Jam mode the infinitely variable practice mode volume control goes from loud enough to aggravate your house-mates to completely silent. In all modes you can select between two different inductive modes (a warmer one and a more midrangey one) plus resistive (bright and modern). The HB125i is built to be driven as hard as you like with any amp of 125 watts or less. It offers two speaker outs and a total bypass for when you don’t want it in-line.

This product is being replaced by the HB130. Once stocks are gone, they’re gone, so grab one while they’re cheap!

This product is currently out of stock and unavailable.

SKU: HB125i Category:

The HotBox 125i is our premium power-attenuator and enables you to drive your valve amp brutally hard into those sweet overload conditions yet output just the perfect volume. Simply connect the 125i between your amplifier’s output and the speaker itself then turn your amp up to overload levels and the excess volume is absorbed leaving you with the true sound of your amp overloading but at a manageable volume.

Why switched instead of variable?

Have you ever owned a 50w amp and wished it was 45 watts? Or come across a 30w AC30 that blows a 60w Fender away? Fact is that watts are a very approximate measurement of volume and messing about with fine-grained control here is pretty useless. What most of us want are just a few setting: A bit less for pub gigs, a bit less again for recording, and a lot less for jamming at home. And so that’s what we offer: Elegance, simplicity, and usability so you can get on with playing because we’ve done the boring complex calculations for you.

There are also several advantages to this, and for one it’s really easy to buy ultra-reliable high-power toggle switches.Ā  Whereas most rotary ones are ultra-low power and in fact, the most common rotary switch is only rated for 0.2 watts with 8 ohm speakers. And yes! You really -do- find that switch used on several commercial products. Shocking! By comparison even our tiny toggles are rated at over 250 watts. And rotary variable rheostats are almost as bad, with many unable to withstand any overload and reaching temperatures well over 500 deg C internally. Our HotBoxes are built to last.

Tri mode, dual inductive attenuation

Choose between warm, vintage inductor tone, a midrange-focussed inductive sound and a bright, modern resistive sound. Whether you’re a doomy blues player, a mid-punchy prog shredder, or an out-and-out big, bad, bright rocker there’s something here for everyone. We’ve started seeing a few companies offering switched inductor responses recently but we’ve been doing it for years before them and I still believe we do it best.


  • Suitable for any valve amplifier up to 125 watts.
  • Tri-mode attenuation with dual inductive options.
  • Available in 16 ohm, 8 ohm and 4 ohm versions.
  • Two fixed reduction levels (Venue and Studio) plus a variable Jam setting
  • True bypass to let your full volume through for A/B comparisons in the studio
  • Works as a Dummy Load (Set volume to zero in Jam mode and you can disconnect your cab safely)
  • Designed and built in Manchester, UK using premium components.
  • Dual speaker outputs so you don’t have to daisy chain your speaker cabs.
  • Lifetime warranty.



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