AmpRx
BrownBox by AmpRx 50/60 Hz
BrownBox by AmpRx 50/60 Hz
5.0 / 5.0
(35) 35 total reviews
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LEARN ABOUT THE BROWNBOX
Note: The BrownBox and BrownBox II have been merged. They are now the same product. You can now use the BrownBox with 120v amps in 50/60 hz countries.
WHAT IS THE PROBLEM AND WHY IS BROWNBOX THE SOLUTION?
Today, we should be receiving 120V AC from the wall, but depending on where you are and what time of day it is, you can receive anywhere from 120V to 129V. That’s not good for your amplifier, or your ears. The BrownBox is an adjustable AC power supply (aka a voltage controller) for your amp or tube gear that helps you run your equipment at the optimal voltage. Plug the BrownBox into the wall, adjust the voltage and then plug your gear into the BrownBox.
Depending on the amplifier, a BrownBox user might discover that modern gear runs optimally at 116-118V, or as low as 108-110V for vintage gear. It’s impossible for an amplifier designed for 110V or 120V to sound or operate anywhere near the way it should at 129V.
The BrownBox features flexible voltage reductions options that let you bring your power input down to an optimal level, resulting in significantly improved amplifier performance.
TECHNICAL SPECIFICATIONS
Input: 120VAC, 50/60 Hz; Standard IEC AC cable.
Output: Two AC Grounded Outlets, Adjustable Voltage Reduction
Power Handling: 5 Amps at 120VAC, 50/60 Hz, up to 540 Watts
Dimensions: Length: 7.5", Width: 4.5", Height: 4.875"
Weight: 3.6 LBS
THE DETAILS
- 120 Volt AC, 50/60 Hz, 5 Amp Voltage Attenuator supplies up to 540 Watts, designed for small or mid to larger sized amplifiers (i.e. Fender Deluxe/Bassman/Twin, Marshall 50w/100w, Vox AC30). Can also be used for parallel or dual amp rigs.
- Easy to read back-lit L.C.D. display enables real-time voltage and amperage monitoring - also useful for diagnostics
- Two adjustment modes to help to fine-tune your voltage
- Proprietary transformer design wound exclusively for use with tube amplifiers, an industry first
- Equal or attenuated voltage output and a 5 amp fuse with in-rush current protection ensures that you will never accidentally overload your amplifier
- Powder coated EMF neutral housing and tough road rugged construction
- Silent, cool operation
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.
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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
Absolutely LOVE AmpRx products.
I bought the Brown Box...leading me to buy the Power Station 1200.....my amps have never reacted and sounded better.
Keep up the Awesome work!
- Coop
Very good product.
This is a tour grade, durable little box! Easy to dial in, and a good safety measure for spikes in power etc. I also like that you can feel a differences. For my '65 Bandmaster head, I find that the BrownBox smooths out the high end and gives the response a fuller, rounded out feel by lowering the voltage to 117v. Thank you AmpRx!
Love this thing. My amp sounds better and the customer service and ease of use is incredible.
Let customers speak for us
from 77 reviewsI 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.

I love The Brownbox! I now have 2 of them and my '72 Marshall Super Lead and '98 Mesa Boogie loves them too! They definitely make a difference in tone and I feel safe that they are running at the voltages that they should, btw extremely fast shipping from AmpRx which I felt I had to mention. Thank You AmpRX!

Great company and Great product!!

Absolutely LOVE AmpRx products.
I bought the Brown Box...leading me to buy the Power Station 1200.....my amps have never reacted and sounded better.
Keep up the Awesome work!
- Coop

I really like the Brown Box. Thanks a lot.

Takes that brittle edge off the top of my Bassman. You don’t know you need it till you get it. Eases stress!

I’m very happy with my purchase of the Brownie. It’s more compact than the regular Brown Box and more suited to the types of amps I gig daily

If you play vintage tube amps from the 50s or 60s you need one of these. You'll be able to tell instantly that you needed it all along...

Shipping was fast, and I got my second "Brownie" in, it looks and operates just like the non B stock Brownie, and at a discount price!

Received my AmpRx mugs patches and swag. Y'all are life savers. Just rack3d my new Power Station 1200...an absolute amp saver. My tracks have never sounded better. Keep up the great work!!! - Coop

The Brownbox is an essential piece of gear. All of my new and vintage amps sound better with the brown box. My house has 123-125volts, everything sounds a little hard at that voltage. Reduced voltage makes my black face amps creamier and my tweet amps sweeter.
