Product Profile: Universal Audio UAFX OX Stomp Pedal

Universal Audio has over the last few years made significant moves to re-invent themselves not only as a manufacturer of professional-grade audio interfaces, plug-ins, and pro audio equipment but also as a manufacturer of high-quality guitar pedals and effects. 

One of the standout products for guitar players that Universal Audio came out with a few years ago was the OX Amp Top Box, a desktop reactive load box and speaker emulator which has become a studio standard for taming the output of your favorite tube amp down to a manageable volume allowing you to go straight to front of house or direct into your audio interface, all the while retaining  the full tonal characteristics of your amp, with or without a speaker cabinet connected.

As a follow-up, late last year Universal Audio released the OX Stomp, a pedalboard friendly stomp box sized version of the OX Amp Top Box incorporating essentially everything found in the OX Amp Top Box minus the ability to function as a load box. The OX stomp is for your pedal board what the OX Amp Top Box is for your tube amp. It is designed to go in your signal chain after your favorite amp-in-a-box. Universal Audio makes a number of great options including the just released flagship UAFX Lion 68 Super Lead Pedal. Placing the OX Stomp into your signal chain gives you the ability to send a realistic equivalent of what otherwise would be your traditional amp cabinet and microphone configuration, along with user configurable studio quality effects.

The OX Stomp is designed to be the missing link between your pedalboard amp and front of house by giving you just the emulation and tone shaping capability of the OX Amp Top Box. The only thing you cannot do with OX Stomp is plug your speaker output directly into it. Whether you are a fan of virtual guitar amp technology or not, there is no denying the ability to realistically recreate the sound of a tube amp on a pedal board is here to stay. The available amp emulators today (not just from Universal Audio but in general) are getting better and better all the time, so much so that it is now viable even for pro level players to leave their amp and cabinet at home and go virtual. 

The top panel of OX Stomp is based around the option to select six user-selected “Rigs.” An OX Stomp “Rig” is a complete sound with cabinet, mics, room, ambience, and multiple effects. The rest of the OX Stomp’s top panel controls are designed for real time adjustment of virtual microphones, room size, speaker drive and output. The two A/B footswitches allow you to select up to four Rigs in real time. The back of OX Stomp has stereo inputs and outputs and a USB-C Port which is there solely to allow you to update the OX Stomp firmware. Further fine-tuning of your Rig can be done via a free, downloadable Bluetooth-enabled App, which gives you a carefully curated list of virtual speaker options, 1 X 12 to 4 X 12 to choose from as well as options for microphones and effect. The end result is a “Rig,” which as mentioned earlier, is a virtual recreation of a guitar speaker cabinet including microphone placement, room ambience and effects. 

OX Stomp is not designed to be an IR loader, it is a speaker emulator and is as far as I know the first one ever designed to fit on a pedal board. Note: OX Stomp only allows you save your Rig configurations from the factory provided options. There is no provision for loading or managing your own IR’s. There is no desktop App available to fine tune your Rigs as there is with OX Amp Top Box. The free downloadable iOS App, which most people will likely access via their phone, does give you a number of options to tweak your Rigs. You can select additional options for room mics and speakers along with EQ and effects including reverb and delay. All the available effects including EQ, Reverb and Delay effects are super high quality as you would expect from Universal Audio. User configured Rigs can be saved as one of the six rigs available to be selected from the from the OX Stomp Box.

As OX Stomp is essentially a performance tool and is designed to be mounted on your pedalboard, I think I understand why Universal Audio decided to go with a Bluetooth-enabled App as opposed to a desktop App for the OX Stomp. That said, I personally found the Bluetooth connection on the OX Stomp to be somewhat unstable (i.e., it periodically crashed), and the pedal had to be completely reset for the Bluetooth connection to be reestablished. Note: the Bluetooth pairing button on the back of OX Stomp is tiny (it is a little bigger than the width of a paperclip). Trying to reset the Bluetooth connection in the middle of a gig would be problematic). Hopefully, a firmware update will address this issue. 

That comment aside, I found the cabinet emulations and effects on OX Stomp all sounded great and convincingly realistic. The OX Stomp is a big step toward being able to leave my traditional amp and cabinet setup at home without any compromises in sound quality.

The Universal Audio UAFX OX Stomp pedal is available now for $399.00 MAP. 

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