The AmpRx BrownBox features flexible voltage attenuation options that let you bring your power input down to an optimal level, resulting in significantly improved amplifier performance.

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. 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.

WHAT'S A BROWNBOX? AND WHY IS CONSISTENT VOLTAGE SO IMPORTANT?
The tone and performance of modern and vintage tube amplifiers rely heavily on the input voltage available from the wall or other power source. Variations in input voltage can drastically affect overall sound and performance and can shorten the life of the components, leading to excessive repairs and frustration.

The BrownBox by AmpRx allows the user to discover and supply the optimal input voltage for their equipment, get a tone they love, and protect their gear in any environment regardless of the normal variations in voltage. BrownBox provides a consistent basis for the signal chain every single time- guaranteed.

How it works: You plug your amp into the BrownBox. Then plug the BrownBox into the wall. Once you turn it on, look at the screen to read the wall voltage.… read more Then you use the knobs to adjust the voltage to find your sweet spot.

While 120V is the expected standard, typical variance both in homes and commercial buildings can range from 116V to 129V. That's not safe for an amplifier, tubes, or tone quality. 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.

BROWNBOX WAS CREATED TO PROVIDE A SAFE RANGE OF OPTIMIZED VOLTAGE REDUCTION LEVELS FOR TUBE AMPLIFIERS
The BrownBox provides a safe range of voltage reduction levels for tube amplifiers. It features flexible voltage attenuation options, an improved user interface with an easy-to-read LCD screen and onboard voltmeter. Supplying the proper line voltage to a tube amplifier ensures it sounds and responds as intended, revealing true harmonic content and preventing costly repairs. Users consistently praise BrownBox for enhancing amp tone, touch, and feel, allowing them to capture their desired tone consistently.

WHY IS VOLTAGE SO IMPORTANT FOR VINTAGE AMPLIFIERS?
Vintage amplifiers and their components built in the '60s and '70s were designed before we had the modern day power grid. Everything about them is meant to operate at 110VAC - 116VAC, which was the typical wall voltage of the era. Today, we can see as high as 129VAC out of the wall. Era-correct voltage levels that the amps were designed around is what will give you that elusive, classic warm vintage tone. A lot of vintage amplifiers sound and feel best around 112-116VAC - you just can't expect the same results with today's voltages.

The problem is that at any point, at any place, you can get anywhere from 120-129VAC out of the wall. It's not good for your tone, and it's not good for the health of your amplifier-whether it's vintage or not. Furthermore, we know that voltage supply can change drastically from club to club, from your home to rehearsal space and even between studios. And sometimes it changes just depending on the time of the day.

BUT WAIT! IT'S NOT JUST FOR VINTAGE AMPLIFIERS! MODERN AMPS LIVE THE BROWNBOX II TOO!
Love your tone at one club and hate it at the next? It's probably the voltage. You're right - it's not vintage, and it probably doesn't need to be sagged to 112VAC to be happy. But even though your modern amplifier is built to operate at 120VAC, and you don't need to reduce the voltage as much as a vintage amplifier, you might just like it more at 118VAC. That's up to you and building your sound. And with BrownBox you can get that consistency in your tone, and hit your magic number no matter where you're playing.
BrownBox will allow you to determine the voltage supply and set it to your preferred level-your magic number-so no matter where or when you're playing, vintage or modern, you're giving your amplifier what it wants to feel good so you can play and sound your best.

Features:

- 120 Volt AC, 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 attenuation 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
- Establishes the basis for your signal chain
- Silent, cool operation

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