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OX Amp Top Box

OX Amp Top Box

Get Legendary Studio Tones from your Tube Amp — Anywhere, at Any Volume.

OX is a premium reactive load box and guitar recording system, giving you perfectly studio-miked amp sounds from your favorite tube amp. OX lets you play and record your amp in its sweet spots — from huge clean tones and edge-of-breakup to fully cranked — at any volume level, and with mic, room, and speaker cabinet emulations at the turn of a knob.

Featuring Universal Audio’s breakthrough Dynamic Speaker Modeling, OX is the first system to accurately emulate speaker drive, breakup, and cone cry — making it the world’s finest speaker attenuator and guitar amp recording solution.

Play and record your tube amp in its tonal sweet spot — anywhere, at any volume, with full dynamics

Get stunning mic and guitar cabinet combinations at the turn of a RIG knob — no miking required

Audition, tweak, and save more than 100 jaw-dropping custom Rigs from compatible iPad, or Mac/Windows computers.

Get authentic “edge of destruction” sounds, complete with UA Dynamic Room Modeling, speaker breakup, and cone cry

The World’s Best Reactive Load Box

The World’s Best Reactive Load Box

With decades of analog hardware engineering expertise, Universal Audio’s dream team of engineers set out to design a reactive load box that retains the tone, dynamics, and feel of your tube amp — no matter how much it’s attenuated. The goal was for your tube amp to “see” OX as an actual speaker — with continuously variable impedance and response — so you don’t lose a drop of tone or playing dynamics.

A Complete Guitar Recording System

A Complete Guitar Recording System

OX’s front-panel, six-position RIG control allows you to quickly choose from complete setups — including emulated speaker cabinets, close mics, ambient room mics, and up to four simultaneous studio effects. OX is also the only guitar recording system to offer a complete selection of expertly placed room mics, giving you the authentic experience of pushing air while recording your cranked amp in a world-class tracking room.

Dynamic Speaker Modeling

Dynamic Speaker Modeling

UA’s groundbreaking Dynamic Speaker Modeling faithfully emulates speaker breakup, drive, and cone cry — an essential ingredient to authentic tube amp tones. Using the Speaker Breakup knob in the OX app, you can control the harmonics and sonic complexity that occurs only at certain frequencies and volume levels on various speakers — far beyond a static Impulse Response system — giving you the same sonic phenomenon that occurs with a real speaker cabinet.

All The Right Connections

All The Right Connections

Not only does OX Amp Top Box feature a front-panel headphone jack for silent practice with your cranked tube amp, it also sports a bevy of connections for all kinds of recording and live workflows. Stereo S/PDIF digital outputs via RCA and optical TOSLINK, as well as balanced TRS stereo line outputs with front panel level control, give you the necessary connections for studio monitors, DAW, or live mixing console inputs. Plus, you can connect any one, two, or three-button footswitch and toggle OX's studio-quality effects on and off.

A Beautiful Software App

A Beautiful Software App

Most guitar products do digital awkwardly. They’re ugly and hard to understand. The OX software app, on the other hand, offers slick, intuitive control over all of OX’s RIG settings via Wi-Fi — letting you tweak, store and recall hundreds of presets from your iPad, Mac, or Windows 10 computer. You can then save your six favorite tones onto OX’s front-panel RIG knob for instant recall in the studio or at a gig.


Watch The Reviews

      Features

      Premium, no-compromise analog reactive load box and guitar recording system for tube guitar amps

      Instant album-quality mic and speaker cabinet tones via front-panel RIG control

      Get record-ready sounds quickly with expertly-placed virtual mics and cabs — no amp miking required

      Five finely-tuned guitar amp attenuation levels, from completely silent to whisper quiet to full band volume

      UA Dynamic Speaker Modeling emulates speaker drive, breakup and cone cry

      World-class Universal Audio EQ, compression, delay, and reverb effects built-in

      Selectable 4, 8, and 16-ohm operation

      Front-panel Headphone out for silent practice with cranked tones

      Balanced TRS line outs and S/PDIF digital outs for stereo recording

      Pair with the OX mobile or desktop app over Wi-Fi for editing and saving RIG presets

      Footswitchable control of OX's studio-quality effects

      OX App Requirements

      OX Amp Top Box

      2.4 GHz Wi-Fi network with internet connection to register (once only)

      (iPad) iOS 12 or iPadOS 13

      (Mac) macOS Mojave or Catalina

      (Win) Windows 10 64-Bit Edition

      Customer Reviews

      OX Amp Top Box

      Overall Rating

      H. Ohl

      August 10, 2022

      Great product - software needs updates

      After recording and releasing our new song (Friends by Frances & Johnny) which was recorded digital, I was searching for a more "living tone". I tried the OX with some old tube amps, Fender Blues Junior, Marshall JCM 800 and a Mesa Boogie and was totally blown away. I love the sound of the OX. Only the software has to be updated. I use a iPad and it would be great, if the app would be also in landscape mode. Also an iPhone App would be great and firmware updates... :-)

      P. Abed

      July 15, 2022

      Attenuator needs fix - and updates. Needed

      Just a checking, about to buy my second unit. The attenuator is impacting my tone, would be great to find a way to bypass the attenuator - just to have the option. Also, when can we expect the next update? I keep hearing this product has been shelved, and we shouldn’t be hopeful for updates.

      J. Skrivanek

      June 11, 2022

      Satisfied customer

      The opportunity to record with UA OX completely turned my current musical life upside down. I started with Captor and after three months I switched to OX - I still can't get enough of the sounds of my tube amplifiers at home with OX. You can listen to how it plays here: https://soundcloud.com/georgos-skrivanos/sets. Good job at Universal Audio! Greetings from the Czech Republic.

      S. Saied

      May 6, 2022

      Wonderful Ox

      I can final let my amp breathe without going deaf or to jail! Love this thing. Quality is unmatched and the emulated cabinets, mics and effects are astounding.

      K. Haavik

      April 26, 2022

      Sounds Epic-

      Z. Drummond

      April 11, 2022

      An amazing unit

      I've been using mine for about a year. Love the versatility, and consistency. The sound I'm able to get from the ox with my amp is better that 90% of the mic'ed tones I can get live. The AC30 cabinet is exquisitely modeled. The only things holding the ox back in my eyes are the lack of midi, and a Hiwatt cab with Fane speakers.

      P. Baker

      March 29, 2022

      Sounds great if you use it right…

      Noticed a bad reviews complaining about harsh distortion. It’s true if you put the input on the box up to high it will sound harsh. I rarely put the input above 5 or 6 to prevent it from clipping. It’s a balancing act depending on the output of the pickups and which amp I’m using. Generally I love it and use it for all my recording.
      Definitely could use an update with more sounds. Leslie effect and a few more cabs and mics would be on my list. I’d also love a few different room sounds too.

      g. laufman

      February 8, 2022

      Pretty damn satisfied !

      The OX is a joy.
      Quiet as a mouse - no white noise at all through headphones.

      C. Dengler

      January 22, 2022

      Incredible!

      There are some reviews here that give only 1 star - after reading several of "those", I realized that those users were probably either (A) doing something wrong, or (B) misunderstanding what this really is. No, it's NOT to be used on MODELER guitar signals. I mean, you COULD, but that's not what the intention is - this device is to be used as an attenuator to your existing amp. HOWEVER, if your existing amp SUCKS, then this will likely return a "sucky" tone. Crap in, crap out.

      As for me, the tone is INCREDIBLE coming from 2 different 5150 50 watt heads (Stealth AND EL34). I'm not ripping on people who misunderstood this process because it is a bit confusing. The only complaint that I have is that each time I turn it back on, I have to go through the complete "re-connect" song and dance to my LAN. Other than that, AMAZING TONE. If you're a "TONE FIDDLER", this will keep you occupied.

      B. Gilmore

      December 11, 2021

      The Box gets 5+ stars but -2 for no release cycle!

      I totally understand that the OX was a miss from a recurring revenue perspective (good for us customers though!). But it would be nice to see some semblance of an update cadence - new cabs, effects, USB capability, etc. Sounds amazing, does everything I wanted, but man it would be nice to have a new toy to play with every year. Oh, and Leslie Cab Sim please!!

      F. Roos

      November 13, 2021

      Unnatural harshness

      It's nice for cleans, but as soon as there are crunch or overdriven sounds involved, you will hear a complete unnatural harshness, that you just can't get rid of, no matter what you try to do.
      This thing makes even a 90s Matchless DC-30 sound bad.

      M. Music

      November 12, 2021

      Two years ago was the last firmware update!

      Congrats UAD on abandon the OX box after a two years period of complete silence!

      OX software is compatible and supported with:
      • (iPad) iOS 12 or iPadOS 13
      • (Mac) macOS 10.14 Mojave or 10.15 Catalina
      • (Win) Windows 10 64-Bit Edition Computer*
      *Tablets and 2-in-1 devices are not supported

      So when buying a new iPad or Mac or Windows Computer OX app will NOT be compatible or supported by UAD. Prices for the OX has gone up lately but support or updates are lacking. One star is already one to many for poor support, non working USB ports, failing Wifi connection with the OX app, NO functionality for saving or loading your own presets and the list goes on...

      N. MACAYA PINO

      September 18, 2021

      Just a couple more cabs and...

      This is a great product. It sounds good, and gives a lot of versatility for someone who just can not make a lot of noise in a home studio. However, the tone i wanted wasn't instantly there. I had to use the provided tools to get it. Like the fantastic eq, or the room mics. Once you start adding some high mids, you get rid of a lot of the harshness, and the low mids gives that thump sometimes you may want
      Finally, i think there are some things missing, like a cab with celestions g12t-75, and the ability to route the room mics or the effects, through the spdif alone, so you can record three tracks simultaneously: left output for mic1, right output for mic2 and spdif for room mics or the effects (i know this is more difficult).
      Still, great product overall.

      N. MACAYA PINO

      September 18, 2021

      Just a couple more cabs and...

      This is a great product. It sounds good, and gives a lot of versatility for someone who just can not make a lot of noise in a home studio. However, the tone i wanted wasn't instantly there. I had to use the provided tools to get it. Like the fantastic eq, or the room mics. Once you start adding some high mids, you get rid of a lot of the harshness, and the low mids gives that thump sometimes you may want
      Finally, i think there are some things missing, like a cab with celestions g12t-75, and the ability to route the room mics or the effects, through the spdif alone, so you can record three tracks simultaneously: left output for mic1, right output for mic2 and spdif for room mics or the effects (i know this is more difficult).
      Still, great product overall.

      K. Schwehr

      August 31, 2021

      More than a game changer

      My OX came on Friday, Saturday it was on stage and Sunday and Monday I did records through my Apollo twin via spdif. This product is no game changer, It is a new game you play. I play a fender hot rod deluxe III and never go over 5 on the gain in the clean channel. Yesterday I did it and turn it to 8 to 10 and all of a sudden there was a drive that made my eyes become wet :D.

      Universal Audio you did an amacing product. I guess everyone who has got a tube amp should have an OX. This product changes my guitar life in so many ways I want to thank you for creating so an amacing product. Once again, Everyone with a tube amp, go out to get an OX, more than a game changer, new bigger game :-) :-) :-).

      T. Schuster

      May 20, 2021

      Packed back up the same night it arrived.

      What is up with the microphonics coming from my tube amp? That is not normal. It’s not ok. And even if it was….how am I suppose to use this to record?! What if I wanted to mic my cab and mix that room tone with the modeled guitar tone? UA…you need to go back to the drawing board with this thing. I even considered getting out my scope and meters and opening up the OX to figure out WTF is going on and how to fix it. But you know what? I didn’t spend $1300 for a mod project. If UA wants to pay me $50/hr, I’ll figure out a solution. I’m not doing it for free and I won’t be paying $1300 for a product that is still under development.

      N. Lloyd

      May 19, 2021

      Perfect.

      I’ve been a big fan of UAD products for a long time now.....I bought the very first UAD PCI cards probably about 20 years ago.....that’s crazy!!!!!
      Anyway.....I’ve got terrible tinnitus from a long career in bands and studios, so loud guitar amps are really not what I want to be near anymore.....
      This Ox Box is a game changer. Took a while to figure it out......I never read the manual so that’s probably why.
      Why has it got USB ports in the back? The seem to do nothing.
      Apart from that, it sounds amazing.
      Better results than I get with cabs and mics.....plus it’s silent. Awesome.
      10/10 UAD. Love it.

      N. Lloyd

      May 19, 2021

      Perfect.

      I’ve been a big fan of UAD products for a long time now.....I bought the very first UAD PCI cards probably about 20 years ago.....that’s crazy!!!!!
      Anyway.....I’ve got terrible tinnitus from a long career in bands and studios, so loud guitar amps are really not what I want to be near anymore.....
      This Ox Box is a game changer. Took a while to figure it out......I never read the manual so that’s probably why.
      Why has it got USB ports in the back? The seem to do nothing.
      Apart from that, it sounds amazing.
      Better results than I get with cabs and mics.....plus it’s silent. Awesome.
      10/10 UAD. Love it.

      G. Heath

      May 14, 2021

      Had high hopes for this, especially at the price.

      So I bought an OX a couple of months back and thought I'd get used to it before I formed any opinion of it. I have a lot of UAD gear and plug ins and this is not in the same league.
      On paper a great piece of kit, BUT it distorts clean sounds on the first 3 attenuation settings, and to my ears has a distinct piezo type quack through headphones. It's more pronounced on IEM cans, less so on decent over ears but still there. Using distortion channels it's not noticeable or lost. I have several decent amps and it does it with all of them, so I'm distinctly underwhelmed for £1050.
      It's been suggested I use a compressor before my guitar hits the amp, but that kinda defeats the purpose I just want my clean amp sound attenuated, not clipped.
      I'm not the only person to complain about this problem there are literally dozens of posts on forums about this, so hoping UAD can do some sort of Firmware update that addresses this.

      b. janzen

      May 7, 2021

      firmware? more like nowhere

      Hope you saved your flashdrives from 2005 cause this sonnabitch can't be updated unless your flash drive is less than 2GB!
      Currently digging up grandmas grave to grab her last flash drive so I can try to make this work in 2021.