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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


      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


      N. Oku

      June 1, 2024

      I can make the sound I thought.

      It's a wonderful equipment that can make the sound you think.

      T. TzwSVsOw

      May 8, 2024



      T. TzwSVsOw

      May 8, 2024



      D. Cohn

      April 28, 2024

      Game Changing Gear

      Believe the hype. OXBOX is is Swiss Army Knife of tone shaping tools. I've particularly enjoyed using it as in interface during rehearsals, allowing me to have some room tone while getting a perfectly recorded, pefectly isolated signal. Great piece of kit.

      R. Duffield

      April 7, 2024

      Every Day Piece

      Could not live with out it , need a second one actually !!! one thing its time for even just a small update to say we have not forgotten ... its time guys ..

      H. Nuesink

      March 15, 2024

      Top Sounds With Top Gear

      Expect a lot from the OX but this is really good. Usable FX and Easy to Use

      F. Doria

      March 15, 2024

      great sounds but constant connection problems

      great sounds but constant connection problems. Considering the cost it is a problem that needs to be solved.

      M. Balanky

      March 1, 2024

      It's been disappointing. I hear crackling on the high end that isn't present in real life. Amps have less headroom in the OX than real life.

      I'm still trying to work through the issues, but there is an artificial break-up distortion on the high end that seems to be input overload, even when my meters are all green. I've tried it with single-ended amps, so there is no chance of an issue from mismatched tubes that the support talks about.

      It works to play quietly at night and I'm in the middle of using it to record an album, but the amps don't sound the same as they do in the room with the same mic and speaker as modeled on the OX. I bought a second one to verify and they both have it. I've heard it on other people's YouTube videos now that I'm aware of it. It is not a silver bullet.

      Besides the artificial distortion I hear, the amps don't seem to have the same amount of headroom as they do in real life. This causes me to find new tones instead of using settings that make tones I like in real life. So, it is like relearning how to ride a bike, which is a drawback. I've troubleshot the thing to death - impedances are matched, tubes are good, tried a new spdif cable, power supply, new ox, verified metering, etc. I sent a sound file to UA, and the support person told me they didn't hear anything. My wife, not a musician, can hear the crackle. ...

      M. Power

      February 25, 2024

      A Dino get's to keep his stuff.

      I'm older, just turned 50, and I've been recording rock guitar since I was 15. I love tube amps and I always go for the 100W tube heads cause I'm a gear snob.

      My Ox Amp Top Box's attenuator is as good as, or better than any attenuator I've owned and being a 100W Gear Snob, that was a few of them. It's sounds great and I forgot I was playing through it within 30 secs and strapping my guitar on.

      The part that blew my mind was the recording capabilities!

      I've really tried to like plugins, and some are pretty good...until I do something that requires rolling off my volume to clean up my sound (Not much of a channel switcher) The plugins just couldn't react well.

      Now, I can run a maxed 2203 and record, with exceptional quality, using headphones at 3 AM.

      PS: The cab emulation is fantastic. When I record, it doesn't even dawn on my that it's software.

      No more words needed.

      My Ox Box is now a permanent fixture in my studio space.

      J. Morales

      February 21, 2024

      Great experience!

      Perfect for record or practice. My full band practice in Luna with headphones. Make more easy for the drummer follow the guitar when track by headphones using a JCM 800. I love it!

      M. Pointon

      February 2, 2024

      Just great

      I've not used this as an attenuator so can't talk about that. I use this for recording and it's just amazing

      R. Thurn

      January 17, 2024

      Ox Box - Perfekt für zuhause!

      Endlich bin ich wieder bei echten Amps und habe die 100000fachen Versuche, dass der Kemper gut klingt, aufgegeben. Kabel rein und aufdrehen. Mit der Ox Box zuhause nicht nur kein Problem, sondern PERFEKT (!!!)

      S. Saied

      January 3, 2024

      Connection Issues

      I love the UA products and I love my ox box, but I really don’t understand the implementation of this Wi-Fi connectivity that you have to go through with the ox box. Why didn’t they implement a USB type connectivity to the computer or even thunderbolt because it was out when the aux came out. another concern as I dropped nearly $1500 on this ox box and there’s been no firmware updates for at least two years years now. Being a software developer and engineer, I know there’s hardware limitations with the Wi-Fi but there’s a USB port on the box, so why not develop software that can utilize that now that technology is moving on with Wi-Fi technology? Eventually you’re not gonna be able to connect your Ox box at all which means you won’t be able to alter any presets.

      R. TARIEL

      December 20, 2023

      Mon meilleur achat

      Je suis tout simplement bluffé par la qualité sonore exceptionnelle qu'il offre.
      C'est sans aucun doute le meilleur achat que j'ai effectué depuis longtemps.
      C'est le compagnon idéal pour tout guitariste cherchant à obtenir un son pro avec ses ampli.

      A. Hathot

      December 10, 2023


      The only downside is that will make you spend money on more analog amps :)

      R. lamprecht

      November 19, 2023

      storing is boring

      have now two of them, sound is great, but if I want to use them stereo, I have to do it twice, boring. Please invent copy presets, can be worth a nobel price.

      T. Nourse

      November 17, 2023

      THE OX BOX is bliss

      I started out using another brand. Sounded ok but the latency issue drove me nut. Tried to work through it but never right. So I bought the Ox Stomp and loves it. So much so I jumped all in for the OX Amp Top Box. Whether playing through my amp to enjoy the tone of driven tube through the speakers or with my apollo twin x, this unit is amazing. My recordings have come alive. All those who complain about the need for an upgrade. Honestly as long as UA keeps up with firmware and software improvements this unit should be good for a long time.

      D. Taylor

      October 26, 2023

      you gotta update it.

      It's great, it really is. However, time marches on and new competitors release new things, and, UA releases new things but don't seem to want to move the Ox. For example, UA just came out with the Lion '68 Super Lead Amp... why isn't that extended to our expensive Ox?

      Also, the Ox needs to be on it's own WiFi when you're tweaking it, which is kinda weird because I'm using LUNA and LUNA wants to be on the internet to 'call home'. So, Luna quits while I'm working on the Ox, I get our of the Ox to restart LUNA, and the Ox quits.

      UA, come dudes. You're smarter than this. Stop treating the Ox like it's an after thought. We paid a lot of money for it, we use your products, keep it updated and let it connect thought LUNA.

      K. Murawski

      October 19, 2023


      I was hesitating for a long time if I should buy this marvellous device or not. It is really pricy (more expensive than my amp!). But since I was struggling for a long time with playing at low volumes at home with good tone I finally decided to order it (found a not so terrible price at one shop). Well - it's a great device, the sounds are great. The lowered speaker output sounds way better than the cheap harley benton I used before.
      The only drawback for this device is not so stable wifi connectivity, and the connection process is not optimal.
      Also - please support horizontal view on iPad. Most of people now have it connected to external keyboards or something and it would be so much more convenient to be able to use it horizontally.

      G. Brown

      October 15, 2023

      Ox Box / Swart Atomic Space Tone Amp

      I first and foremost purchased the Ox Box for attenuation.
      For or my clean guitar tone I use a Swart Atomic Space Tone Amp, as it will not start breaking up until after 9 o'clock on the 12 point volume control and sounds sublime.
      Before purchasing my Ox Box I used a Swart Nite Light for attenuation, although a great piece of kit it didn't offer me the correct level of attenuation I required.
      The Ox Box does this and with the availability of the on-board amp / microphone modelling, opens up a whole new world of sound which I am only just discovering.