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Everything In Music - Since 1958
Everything In Music - Since 1958

AmpRX BrownBox Voltage Optimization Unit

by AmpRx
Original price $0.00 - Original price $0.00
Original price $0.00
$349.00
$349.00 - $349.00
Current price $349.00
Inventory Status:

❓ Out of stock
About Inventory Status


Questions?
Call or text us at 301-946-8808.

In stock: It is in stock and available to ship or pickup. We can usually ship or have these items available for pickup by the next business day if they don't require inspection, special handling, or setup. Our pickup location is 11151 Veirs Mill Rd. Silver Spring, MD 20902.

📆 Preorder: It is on the way to our warehouse. We can't predict when preorder items will arrive due to current supply chain issues. If you place an order for one of these items someone will contact you to estimate the delivery date.

Out of stock: We don't currently have it available but you're not out of luck yet. We still may be able to get it. If you order one of these items we will contact you with an estimated fulfillment date. You have the option to cancel the order if you change your mind.

Special order: The item is so special that it needs to be custom ordered for you. Some of these items are works of art and have to be made individually. Orders for special order items must be prepaid and we cannot accept cancellations or refunds.

█ Sold out: We don't think we can get this item because it was either discontinued by the manufacturer or was limited in quantity. If you want or need this item call or text us. Sometimes we can help you track down the item through other sources or help you find something similar.

About Item Conditions


Questions?
Call or text us at 301-946-8808.

New: The item is brand new as received from the manufacturer with a full manufacturer warranty. Instruments such as guitars, snare drums, drum kits, brass and woodwind instruments may be opened for photography and quality control inspection and may not be in a factory sealed box.

Mint or Open Box: The item may have been opened and tested but has been repackaged. The original packaging may have superficial issues but the item itself and any originally included accessories are in perfect, like new condition.

Display Model: These items are so cool that we put them on display in our legendary shop. The condition is brand new as received from the manufacturer with manufacturer warranty. Rest assured, these items undergo a very careful inspection before shipping.

Demo: These items have been on our sales floor for demo purposes and will likely show signs of use. The original packaging may no longer be included, but you can be assured that you are receiving an awesome item and an awesome price.

Used: The item is used. These item may have varying degrees of wear. Please read the description for information about the condition of the item. Used items do not carry a warranty.

B or C Stock: Factory refurbished. These items were purchased from the manufacturer in a refurbished condition. They will show some cosmetic issues, but nothing that would impact performance. Being that these are sealed from the manufacturer, we generally do not open these to photograph the cosmetic issues. They are guaranteed to work and may have a limited warranty or you may purchase an extended warranty in some cases. Please see the listing description for item specific information.


Bring Your Amp To Life With The AmpRX BrownBox Voltage Optimization Unit

BrownBox was created to provide a safe range of voltage reduction levels for vintage tube amplifier designs. The same, era-correct voltage levels that the amps were designed around. Their products can also be used with modern solid state amp designs protecting them from potential over voltage conditions. 

The dynamics of a vintage amp supplied with the proper line voltage are optimized and will sound and respond as originally intended, revealing the circuits true harmonic content. This is the starting point, the basis of the signal chain, and where serious musicians begin creating a signature tone.  

Most vintage tube amps respond more harmonically and touch sensitive with optimized voltage. Placing these circuits back into balance reveals the authentic tone fundamental of the amp, tone that can truly blossom. For the Tube Tone Purist, no pedal or attenuator can come close to replicating the heavenly response of dry, purely saturated tubes. Pedals and attenuators have their place, keeping in mind that they color your tone, not create it.

Everyone can enjoy multi-dimensional, pure tube tone, if they just know where to start. 

BrownBox is not a variac. Unlike a variac, Brownbox cannot accidentally harm or destroy your amplifier. The maximum input voltage available using BrownBox is your regional line wall voltage, in bypass mode. All other selections are reduction levels that you determine sound best for your amp. 

BrownBox employs a proprietary custom-wound toroid transformer, intended for use with one amplifier. Check you amps input wattage rating  prior to use. Their proprietary transformers are custom wound exclusively for use with tube amplifier designs, but can and should be used with Solid state circuits.

Technical background interest:

Consider this: testing with a non-modded vintage fender Bassman (5F6A) as part of our testing platform throughout the design process, one of the most important electrical design elements was measuring the variable current levels that the amp would draw at different line levels.

Testing was performed at control levels between 105 V.A.C. to 126 V.A.C. Testing indicated current levels of 0.7 and 1.8 amperes consecutively. Knowing those factors enabled AmpRX to build in exceptional electrical stability by creating a transformer with a current rating 2.5 times greater than the highest test level result of 1.8 amperes. 

BrownBox was created by a team of experienced player/technicians with the professional player in mind. That meant first it must be intuitive and easy to use every time. Secondly, it must also have a road rugged design and be able to take abuse. Thirdly, it must be practical  and superior to any other voltage reduction option.

BrownBox  is completely proprietary in design and function and comes with a lifetime warranty with normal use. 

Features
  • Easy to read, back-lit L.C.D. display enabling real-time voltage and amperage monitoring, also useful for diagnostics.
  • Tough road rugged construction.
  • Proprietary Transformer designs wound exclusively for use with tube amplifiers, an industry first!
  • Filament soft-start in full reduction mode. 
  • A powder coated EMF  neutral housing. In-rush current protection, fused over-load protection.
  • Silent, cool operation.
  • Custom wound 5 amp proprietary  transformer that will supply 540 watts max@ 120 Vac. Designed for Mid to larger sized Amps, Fender Bassman, Marshall 50s/100S etc. or for Parallel or ( DUAL) amp rigs. Be sure to Check the Manufactures info plate on the rear of the Chassis for input watt requirements or simply call us, we love to help.
  • Made in the USA.

Why Voltage Optimization? Voltage Optimization provides numerous benefits: 

  • Establishes the basis for your signal chain and the starting point in building a consistent signature tone. Earlier power tube saturation equals earlier break-up at more usable volume levels.    
  • A smoother tonal shift toward even order harmonics, revealing the amplifier's true designed tone fundamental.  
  • Lower internal voltages = lower dissipation = longer component life.

Manufacturer: AmpRx
Model: BROWNBOX
SKU: I514709-N-0-WHXA


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Maryland, Virginia, and Washington DC's legendary music shop. Family-owned and operated since 1958. Buy gear the way it was meant to be bought, from a store that's been there through it all and has the vibe to prove it. We're staffed with musicians and industry experts, people that live and breathe music gear. Our mission is to help you find the right gear for your project, that thing that will bring you the most joy out of what you do. We're an authorized dealer for almost every brand, we stock items the other stores don't, so you can try before you buy. Stop by our Wheaton, MD showroom and see for yourself.

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