AmpRx
B-Stock BlackOutBox: Limited Edition Halloween BrownBox
B-Stock BlackOutBox: Limited Edition Halloween BrownBox
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A note about B-Stocks: One might call it “scratch-n-dent”, another might call it “relic'ed” (if that’s you, we won’t even charge you extra!). In any case, these units are perfectly functioning on the inside, but have minor imperfections on the outside. Some examples include small paint chips and color inconsistencies.
Tame the power, unleash the tone—no tricks, just treats!
Beware the Voltage Vampires! 🧛♂️ This Halloween, don’t let your amplifier fall victim to the horrors of high voltage. The BrownBox will tame wild power surges that haunt your gear, and restoring the spooktacular tone you crave. Whether your amp needs 116V or 110V, the BrownBox ensures it gets just the right amount of juice—no tricks, just tonal treats! 🎃
When today’s power sources send out dangerous levels from 120V to 129V, it’s enough to make your amp scream! With the BrownBox’s adjustable voltage reduction feature, you can banish those voltage demons and resurrect your amp’s true sound. Discover spine-chillingly precise performance as the BrownBox revives both modern and vintage gear, delivering the optimal voltage every time.
THE SPOOKY DETAILS
- ⚡ Voltage Slayer: Handles up to 540 Watts / 5 Amperes and is perfect for amplifiers ranging from small to large monsters like the Fender Deluxe, Vox AC30, or Marshall 50W.
- 🧙♂️ Magic LCD: A back-lit display shows you real-time voltage and amperage, allowing you to monitor your amp and avoid any shocking surprises.
- 🕸️ Dual Adjustment Modes: Two modes to help fine-tune voltage, giving you control over every eerie sound.
- 🦇 Foolproof Protection: With in-rush current protection and a 5-amp fuse, the BrownBox protects your amp from overload so the ghouls of over-voltage can never strike.
- 🛡️ Tough as a Tombstone: Rugged, EMF-neutral housing ensures silent, cool operation—even in the scariest of conditions.
Keep your tone hauntingly perfect and protect your amp from voltage terrors. This Halloween, let the BrownBox be your amp's guardian against the ghosts of unstable power!
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Learn How to Use the BrownBox
Let customers speak for us
from 89 reviewsRequired equipment for any tube amp. Built like a tank, these look as good as they perform!
The plate voltage on my vintage silver panel Deluxe Reverb is now in a safe range. I feel comfortable running vintage power tubes and it sounds so good. It has just the right amount of sag that was previously missing. Thanks AmpRx!
Yes, I know it's only January, but investing in my amp with a Brown Box was the smartest decision I've made in a long time. Thanks AmpRx. Now I'm safe and secure!
My wall voltage is anywhere from 118v to 129v. I've found my Two Rocks to sound ideal biased at 30ma idle per tube.. Well, if the wall is 128v when I bias to my preferred 30ma per tube, and the next time I play the wall is 120v, my tubes are only idling at 27ma… enough to notice a little stiffness, with less smooth high end, so I’m messing with the gain and EQ trying to find the tone from the night before.
Now I set my Brownies to 120v,, bias the amps, and keep it at 120v. My amps always sound great. I turn my amps on and the tone is there…every time. So I can spend my time playing and not tweaking.
This is a gift for a talented relative, so I can only say it is a heavy, solid piece of equipment that arrived in good order. Nice people at BrownBox who respond to emails.
Received exactly as advertised! Great build quality and functionality. I may need to buy another one!
Excellent product - it's the piece of gear I didn't know I needed. The feel of the amp "under the fingers" is amazing. My pedals seems to sound and feel "better" as well, and I know my amp is happy too.
Love the Brownie. I have not been able to find anything that would make it B Stock - did you guys acidentally put a new Brownie in a B-Stock box? It works perfect delivering 117 VAC to my Mesa Boogie which is by the way what the user manual calls for!
BrownBox has been instrumental in keeping my vintage Ampeg SVT operating flawlessly on the road, where voltages can fluctuate wildly!
congratulations to the team of AmpRx
Excellent product. Just what I needed for my vintage 1950s Fender amps.
Really like this unit.
What sold me for this product was Dan, Mick from the pedal show on you-tube and the ability to plug in multiple amps via the 4 receptacles in the back.
I can’t explain how happy I feel with the BrownBox. The difference was immediate — more clarity, cleaner tone, more headroom. I connected my vintage Fender Bassman and Matchless (my oldest amps) and wow, what a relief to know they’re running at the right voltage and not suffering anymore. The sound is so much more alive and natural.
If you care about your amps, especially vintage ones, this is a must. It gives me peace of mind and the best tone I’ve heard from my gear in years. Absolutely recommended!1000 stars!!!! Daniel Uribe
I can’t explain how happy I feel with the BrownBox. The difference was immediate — more clarity, cleaner tone, more headroom. I connected my vintage Fender Bassman and Matchless (my oldest amps) and wow, what a relief to know they’re running at the right voltage and not suffering anymore. The sound is so much more alive and natural.
If you care about your amps, especially vintage ones, this is a must. It gives me peace of mind and the best tone I’ve heard from my gear in years. Absolutely recommended!
Great pedal for modern amps. I live in the Mojave desert and AC is actually too low at times (115v). Being able to bump up the voltage is very useful. Overall, I suspect that the filtration in the unit contributes to a smother performance and sound, whether or not you are altering the AC.