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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

      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

      S. Burilina

      May 16, 2023

      OX Amp Top Box

      The best box.Thank you!!!

      S. Burilina

      May 16, 2023

      OX Amp Top Box

      The best box.Thank you!!!

      H. Brett

      April 19, 2023

      Perfection !!

      I’m definitely blown away on how usable this jewel is. Man it’s Smokin when tracking and playing live gigs. I built a 20K guitar rig with Bob Bradshaw back in the day and that was all high end studio gear. Being use to hearing the quality there’s no going back. Now I have a really sweet pedal board instead of the rack effects. I love it! Adding the OX BOX adds to my arsenal with flying colors.

      Thanks for building this quality tool & for going above & beyond.

      功. 佐藤

      April 11, 2023

      音は最高

      UAD pluginでFender 55' DeluxeをLineにして、ラックプリアンプ(bognerやfryetteやsynergy)やペダルプリアンプ(KochやOrigin Effects)を投入した時と同じ様に、OXは歪みに食いついてきます
      スモールアンプ(Mesa mark V:25やSuhr Pt-15)を所持しているとしたら、ノイズフリーで
      かつ 大きな音量、最高の音色とルームリバーブを得る事が出来ます

      G. Doran

      April 1, 2023

      Amazing!!!

      This is probably the most useful tool for guitar recording. I have never felt this strongly

      J. Bradley

      April 1, 2023

      Amazing Piece of Kit

      Over the moon with the OX, it sounds absolutely fantastic and so versatile!

      C. Hevey

      March 21, 2023

      Excellent produit

      Excellent produit de qualité… besoin d’autres update pour incorporer entre autres des cabinets de basse et plus d’options pour les placements de micros.

      G. Teekens

      March 16, 2023

      Great Product!

      Lifesaver & Timesaver. Sounds great and works like a charm. The presets are great too!

      C. Dengler

      March 12, 2023

      YES YES YES

      GET THIS. I was questioning the value of this in the studio - no longer. THIS IS the unit you need in order to better record your guitars and bass. Unreal. I LOVE this thing. Best purchase of the year.

      D. Garrett Jr

      March 12, 2023

      Very nice, but lacking....

      First off, I'd like to say I love Universal Audio stuff..... BUT, this is an item that needs more attention from their R&D department in my HUMBLE opinion.
      First problem: To use the software you have to register it. The registration is a complaint I hear from everyone, and one of my complaints. You have to hookup to a 2.4 Ghz network to register.... that's just plain DUMB.
      2nd problem: No support..... don't try calling UA for help, they don't answer the phone and their support line for this is not working. GOOD LUCK!

      Actually there are some other issues too... but I love the attenuation! I would suggest looking at other attenuators (BOSS WAZA) to compare before purchasing. I have not done this & now I think that may have been a mistake.

      L. Beliveau

      March 7, 2023

      Network set-up issues

      Fantastic power amp attenuator. Great sound through the stereo outputs. Software could be enhance (more effects choices) and control with an external device (via USB or Foot switch, wifi not reliable). Network set-up could be more user friendly, good thing it stays set after the first connection. i can appreciate my 100 watt plexi clone without turning deaf.

      K. Tomita

      March 6, 2023

      ハードオフのアンプコーナーが宝の山に

      エレキ ギターの音をオーディオインターフェースから録音するために使用。音質がすばらしい。自宅でこのクオリティで録音はできません。本当に買ってよかった。プラグインみたくたくさんのギターアンプはいらなくて、欲しいトーンは1つか2つ憧れのENGLアンプを夜中でも爆音で(ヘッドホンの中)鳴らせています。OXが理想を叶えてくれました。そして、これまで素通りしていたハードオフのアンプコーナーが宝の山に見えます。

      V. Beccia

      March 5, 2023

      Still Awesome although FW and SW need updates

      This is a great product. Built like a tank and sounds great. It' s showing it age in todays market though.
      Don't know what's happening upside of UA's cranium but this diamond only needs a polish via its FW and Software and could potentially remain a formidable unit well into the future. Sounds great and keeps you playing and creating! Still love it!

      W. Hemenway

      February 27, 2023

      OX BOX is great but needs IOS updates

      Hardware is amazing but you need to update your IOS software for multitasking and landscape view. Also the ability to reposition mics to different places on the cabinet.

      F. Moleirinho

      February 27, 2023

      Simply brilliant!

      I’ve been using an old tube combo amp (circa ‘70s) into the OX, to a UA 4-710, into an Apollo. The variety of sounds from this simple set up is surprising, from clean to crunch, to grunge, even metal. Very well made, solid hardware.

      R. Trevor

      February 24, 2023

      Leslie

      I love my OX.
      Having said that, we need a Leslie cab emulation !!!!

      G. Cowan

      February 22, 2023

      Perfect for guitarist home studios

      I am a guitarist that has a small studio setup at home for songwriting and practicing. I’ve never been happy using amp sims and digital plugins for my direct guitar tone. The Ox has been awesome for me getting a tone I’m happy with and letting me use the amps I normally gig with. Looooove it!!!

      C. Katches

      February 16, 2023

      Amazing box but needs an update!!!!

      PLEASE FOR THE LOVE OF GOD, GIVE US A 15'' SPEAKER OPTION!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
      This thing sounds fantastic on the given cabs, but is years overdue for a proper update hence the four stars.

      L. Pellecchia

      February 6, 2023

      Great for computers less for loudbox

      I bought this mainly to use as a loudbox and was a little disappointed, I used a couple of the best 12 awg speaker wires available on the market however going beyond position 4 the sound degrades excessively losing too much treble and bite, it doesn't can compensate with the EQ of your amp or guitar effects pedal. contacted customer service for explanations and advice they repeated "due to fletcher munson effects quieter sounds will have more midrange and less bass/treble" repeating it to me several times although I already understood it at the first, but it is not possible that it already happens at position 3 in such an intrusive way! it is unusable from 3 onwards. the difference in decibels between position 5 (no attenuation) and 4 (first level) is minimal and certainly not worth the cost of the product. I want to hope that for other speaker and amp combinations it works better than with my custom hiwatt and fane speaker. the other functions are excellent: speaker simulator, microphones, presets, output to audio interface and mac all beautiful and high quality. not to the level of the loudbox only functions.

      B. Windel

      February 3, 2023

      I LOVE this thing.

      What a game changer. I have this connected to my Apollo via the optical connection and it sounds SO good. Love it. Being able to use my pedal board + 3 amps and yet keep it all contained in either my headphones or nearfields is just a beautiful thing. The power soak / attenuator bit is great too, don't get me wrong, but I don't use it as much. The desktop app on macOS works great - no issues whatsoever.