Universal Audio introduced their first three UAFX Pedals in 2021, and with the release of 12 new pedals in 2023, the line now has 18 different pedal options available for a complete instrument recording and/or signal processing chain. All pedals share one of two form factors: The first round of pedals are all slightly larger and generally have two footswitches, two or three smaller switches, and six knobs to tweak parameters. These pedals typically model three different but related devices. The larger pedals can also connect to an iOS device and app, allowing for additional parameter controls and effects, and a USB-C connecter accommodates firmware updates. The second round of pedals have one footswitch, one small toggle switch, and up to five parameter knobs that are dedicated to modeling one device. All pedals have unbalanced 1/4-inch inputs, and the larger pedals can run mono or stereo, but the smaller pedals are simply mono. These pedals use UA's proven analog modeling algorithms and ARM processors. Sure, many of these effects are also available as plug-ins (Spark or UAD versions), but sometimes it's better to have a dedicated piece of hardware that you can drag around the studio to use on everything and doesn't need to connect to a computer! Several of the pedals even have unique effects that are not available as plug-ins.

A few notes on all the pedals. UA has been working on hardware and software integration for over a decade now, and since releasing their Unison preamp technology on the Apollo Twin interfaces, one of the aspects they understand and do well is impedance matching. All gear has different output and input impedances (guitars, amps, mics, preamps, etc.), and this impedance can affect and change how a piece of gear sounds. One of the big differences between these pedals versus using a plug-in is that the software built into these pedals is optimized for use with its hardware, allowing for more accurate modeling compared to plugging a guitar into a random interface's DI. This is a good thing! Secondly, it's important to note that because these pedals are essentially tiny, dedicated computers, they take a few seconds to boot up and use a fair amount of power in contrast to older analog pedals. The small pedals need 250 mA minimum, while the larger pedals need 400 mA. Users need to make sure there's enough power for these in their rig or they may not behave properly. I found if I strung too many of the pedals together on one old-style wall wart supply some of the pedals wouldn't work properly, but as long as each pedal had enough amperage they were fine.

After using these UAFX Pedals in their studios for several months, some of the Tape Op crew shared their thoughts:

UAFX amplifier pedals

Though not the first pedals introduced, the amplifier emulation pedals form the foundation of the UAFX line. The first three pedals were the Dream ‘65 Reverb-Amp (1965 Fender Super Reverb amp emulation), the Ruby '63 Top Boost Amplifier (1963 Vox tube amp modeler), and the Woodrow '55 Instrument Amplifier (1955 Fender tweed amp reproduction). Like all the UAFX Pedals, they share the same form factor with different graphics and labeling to correspond to the different functions of each pedal. Since ruining a few records in the early aughts with the Line 6 POD [Tape Op #22], I've been skeptical of digital amp modeling software. However, the UAD amp emulations have slowly won me over. As their amp plug-in models were released, I began using them when mixing to fix poorly recorded guitar tracks or to bring out more edge to clean guitar tracks, and I begrudgingly had to admit that they sounded pretty good. I gradually started to use them for tracking guitars with the idea that the (direct) tracks were scratch tracks, but they almost always sounded really good and often became keepers. When the pedal versions became available, I was eager to try them out in the studio. These pedals have been getting a lot of use at Panoramic, both in the main studio and in our B-room. Sure, we have some nice vintage tube amps, but we're also in a residential area and our B-room is more of an overdub space without extensive soundproofing, so being able to track guitars direct that sound this useable is useful. The pedals have seen a fair amount of use in the main tracking room as well, both as a way to track guitars live (direct) with zero bleed onto drums, and as a solution for late-night guitar overdubs when other folks are sleeping.

Sure, we could do all this with the UAD plug-ins, but it's nice to have a physical unit that is DAW agnostic, and one that we can plug into and directly interact with that does not require using software. I should also mention that all the UAFX amp modeling pedals can be used with the iOS/Android UA Connect mobile app, which expands their functionality, but they also work fine without the app. I have not downloaded the app, as what I like most about these pedals is that I don't need my phone or computer to operate them. Also, as these pedals are used by lots of guest artists and engineers, I wanted to minimize any extra steps for ease of use. Tape Op's Gear Reviews Editor Scott McChane has been using the app, however, and is excited about the additional possibilities in his workflow: “The connectivity with your mobile device via the Pair Bluetooth button on the rear of the pedal allows for quick customization and expanded features, such as real-time control. Live-tweaking the Oscillation and other settings of the Galaxy ’74 Tape Echo & Reverb pedal (for instance) with my phone dished out some of those warbly tape delay sounds (with the trashy, glittery reverb) that we all know and love. There’s just something intangibly cool about tapping out a delay time with the heel of your hand while dialing in the Echo Rate with your fingers.”

My two favorite amp pedals are the Dream ‘65 and Ruby ‘63, as I like to take advantage of the onboard reverb and vibrato, respectively, and the tone of these two amps make up 95% of the tones I'm usually looking for. I should also mention that while using these amp pedals for guitars is the obvious choice, they also get quite a bit of use with our Wurlitzer and Rhodes electric pianos. It seems the electric pianos end up going direct (more often than not) as they typically end up in the control room for overdubs, but with the UA amp pedals we can add some amp tones to the direct chain. We recently had producer/engineer Anthony Razo at Panoramic working with the artist Andrés on some new songs for his upcoming album. They used the Dream ‘65 and Ruby ‘63 pedals extensively for all the guitar tracking. When it came time to tour, Anthony and Andrés left their real Vox amps at home and took two Ruby ‘63 pedals on the road instead. “They're so much easier to carry around, and the emulation at this point sounds as good as our old amps,” Anthony said. He further commented, “The Ruby ‘63 has a room emulation function that has added a whole new dimension to our tone, and it feels like an amp in a room.” The dichotomy here is that these pedals sound amazing and are physical devices you can hold in your hand, but they are small! Nobody likes lugging heavy amps around, and that's a big positive for these pedals.

As we were getting close to the deadline for this review, UA released two more large format pedals into their amp family. First off is the Lion '68 Super Lead Amp, an emulation of the classic (and loud) 100 watt Marshall Plexi amps. Tape Op's Corey Reidy has owned several Marshall Plexi's over the years, and after using the Lion ‘68 for a few weeks this is what he had to say: “I once had a Marshall amp fry in the studio, a plume of smoke billowing out like a cartoon mishap, with the engineer looking over and saying, ‘Vintage gear, vintage problems.’ I don't have this problem with the UAFX Lion '68 pedal. Its three models (Bass, Lead, Brown), the functional yet beautiful-in-its-simplicity Marshall front panel Presence and 3-band EQ, and the Room knob (which is the absolute under-the-radar star of the show, simulating room size while adding vibe) are all packed into a box a slightly smaller than a Nintendo Game Boy. Recording directly into a DAW I can remove major variables of mic placement, speaker selection, and room interference. The pedal comes with three options for cabinets and mics to start, but when registered online there's access to three additional cabinets and storage for additional presets. The ability to put together a high-gain Marshall tone at a low volume level can’t be understated. The Lion '68 covers the EQ spectrum, while the Bass control counterbalances the Lead and Brown models, giving the option to utilize the pedal for dark, warm rhythms, those rolled-off center-mass lead lines, or punchy-growly bass. The two lead options give precision, clarity to chaos, haywire, and beyond. Because all of these options are physically controlled, it doesn’t take hours to cycle between them – it takes minutes to spin knobs and flip switches. Comparing the tone and sound of the UAFX Lion ‘68 to my years of experience with Marshall Plexi amps, I came away stunned, and I’ve only scratched the surface of what this pedal can do.”

Lastly, UA recently released the OX Stomp Dynamic Speaker Emulator pedal based on their Ox Amp Top Box [Tape Op #128] and speaker emulation recording system that has become a standard for guitarists working in the studio. OX Stomp doesn't work as an amp load device; you can't plug the speaker output of your amp head into it like the Ox Amp Top Box allows. However, the pedal allows you to take all the OX’s speaker and mic emulations and pair them with any of the UA amp pedals, or any amp emulation or pedal chain, for that matter. OX Stomp offers six different speaker cabs available directly on the pedal, and 22 total speaker cabs available with the iOS app. Each speaker rig has two separate mics, switchable between six different dynamic, ribbon, and condenser mics. A Room control adds ambience, and a Speaker Drive control lets us dial in how hard we're pushing the “speaker” and how old and broken-in the “speaker” is. There is also a built-in 1176 compressor emulation, plus a stereo delay, stereo plate reverb, and 4-band EQ available with the iOS app, all of which can be added to the six onboard rigs. After using OX Stomp with different amp stompboxes, I'd say that this is a finishing pedal. The effects are not drastic in the way that some of the amp or effect pedals can be, but the OX Stomp allows you to fine-tune the sound of your amp in the “room” and how your amp is interacting with your “speaker.” You can dial in a very useable guitar tone with OX Stomp at the end of your chain. The other cool thing about this pedal is that you can use it to make your final output in stereo. Guitars are, of course, inherently mono, as are most traditional pedals. For recording direct, it makes a lot of sense to keep the signal in mono up to the amp and then use the mono-to-stereo capability of the OX Stomp to make your final output stereo – tweaking how the amp and speaker sounds in the room and dropping that into your track.

UAFX compression & gain pedals

Next up in the UAFX Pedal line are several gain and compression pedals. The first release in this range was the Max Preamp & Dual Compressor as a large format pedal, which has models of the UA 610 tube preamp [Tape Op #27], plus the LA-2A [#26] and 1176 compressors, and the MXR Dyna Comp compressor pedal. Next up, UA released small-format pedals modeling UA’s own 1176 and LA-2A compressors. Tape Op's editor and founder, Larry Crane, has been using the new UAFX 1176 and LA-2A pedals at his Jackpot! Recording Studio for the past few months. Here's what he had to say: “After trying a number of stompbox compressors on guitars over the years, outside of the Union Tube & Transistor LAB [#127], I gave up. Many I tried never sounded anything like a studio unit to me, with flabby tones and weird attack and release characteristics. I've even run electric guitars into a DI, through a rack-mounted 1176, and back out to an amplifier – the tones were incredible, but that's a lot of cable runs. With UAFX's Studio Compressor line – Teletronix Model LA-2A and 1176 – we have two digitally-recreated stompboxes that do this compression properly. I love both of these on clean electric guitars for getting those Byrds/Tom Petty tones and beefing up melodic parts. The 1176 is slightly punchier, but the LA-2A certainly has that classic tube and optical circuit vibe. There are many extra features, but I have to mention the 1176's Dual mode – it'll make your guitar start busting up like Keith Richards! If I could buy just one of these, it'd be the 1176, but they feel a bit different from each other and help me get clearer guitar tones in the studio.”

UAFX reverb, delay, & modulation pedals

Lastly, let's go back to the beginning with the first three UAFX Pedals that were introduced in 2021; the Golden Reverberator, Astra Modulation Machine, and Starlight Echo Station. Sharing the same larger form factor and UAFX Control app, the Golden Reverberator does the Fender Pro Reverb spring-style emulation like the Dream ‘65, plus EMT 140 plate and classic Lexicon 224 reverb models. The Astra pedal adds emulations of the 1965 Fender Twin tremolo, plus the Roland Chorus Ensemble and MXR Flanger/Doubler effects. Larry has been working with the Astra recently, and here are his thoughts: “The Astra Modulation Machine is touted as delivering ‘bucket-brigade chorus/vibrato, studio flanger/doubler, and tube-driven tremolo effects,’ and it does. The pedal features six knobs and three switches, plus presets and stereo operation. It's harder to navigate for me than some pedals, but it's also difficult to make it sound bad so that's a plus! Among the three main modes, I am a sucker for the MXR Flanger/Doubler effect, and this pedal's Flanger Dblr captures that 'whoosh' well. The Chorus Brigade goes for the classic analog Boss pedal tones and does it well; Andy Summers would approve. The Trem 65 settings work in that Fender amp world, but I'm a little baffled why a pedal featuring time-based effects would have a volume-based tremolo on board. Any reticence I had about this pedal vanished once I skipped my guitar amp and plugged the stereo outputs into a quality DI. All the modes spread out across the stereo spectrum in that way a Roland Jazz Chorus amp does, and suddenly I was dreaming up ways to incorporate this in tracking sessions. Now I just need to set up two guitar amps!”

Dana Gumbiner reviewed the Starlight Echo Station back in Tape Op #145, and here's what he had to say: “The Starlight’s Tape EP-III emulation of the Echoplex EP-3 tape delay is awesome, with adjustable wow/flutter and noise with plenty of opportunities to drive it into saturation. The second emulation, Analog DMM, recreates the classic bucket-brigade delay sounds of the late ‘70s/early ‘80s, with some enhanced elements such as longer delay times (up to 1 second). The Precision delay mode is a clean digital delay with some extensive modulation options. Interestingly, if you register the pedal with the UAFX Control mobile app, you can add an emulation of the UREI Cooper Time Cube, which is just as fun as the UAD version.”

Larry has been using the newly released small format Evermore Studio Reverb based on the classic Lexicon 224 digital reverb unit; here's his take: “The Evermore is a versatile Studio Reverb pedal, with settings for Room, Sm Hall, and Lg Hall, with a Predelay option switch on the back (it gives a breather before the reverb swells in). Besides the very usable reverb sounds, the 3-band "EQ" of Bass, Mid, and Treble decay times is the kicker for me; how often can one easily sculpt out the reverb tones they really need for a part to sit in a track? Push the Mid all the way, and crazy sustains bloom out of the track, plus the Mod control can mess it up in a cool-ass way! Based on Lexicon 224-styled sounds, it also can do spring or plate style reverbs without the boings and resonances, making this a pretty cool find.”

Scott has been using the two recently-released Galaxy '74 Tape Echo & Reverb and Del-Verb Ambience Companion pedals, both of which focus on time-based effects. Galaxy '74 emulates the classic Roland Space Echo, while the Del-Verb bills itself as an “Ambience Companion,” and we all need a good ambient friend right? Del-Verb has several different emulations, including a spring reverb, a plate, and the Lexicon 224 digital reverb, all from the Golden Reverberator pedal, in addition to Echoplex tape and Electro-Harmonix Memory Man bucket brigade delays. Here are Scott's impressions of these two pedals: “I own the UAD Galaxy ’74 plug-in, and it’s become an in the box go-to for me as a vintage-tinged lo-fi effects return – or as an insert on a vibey guitar solo. There’s no denying that analog tape echo units look cool as hell sitting on a rack, but they can be a headache, with much maintenance and calibration. Tactile physical pedal knobs and switches control Echo Rate, Feedback, Echo Volume, Head Select (for single, double, and triple “tape” head delay styles), Input Volume, Dwell, and Reverb Vol (volume) – a Main/[Alt] toggle turns the previously mentioned controls into Tape Age (very cool), Bass, and Treble knobs (and are noted on the panel). On/off and Tap/Hold footswitches round out the pedal's physical controls. I feel like I can be more adventurous and intentionally set the delay time behind the beat in a cool/dubby way with this pedal, whereas I'd probably be less likely to do so in the plug-in version of this effect. On my next mix I'll turn on my Galaxy ’74 pedal instead of inserting a plug-in!

I cannot disagree with the 'Ambience Companion' label on the Del-Verb. If I had to have just one effect, this would be it. I've got a few cheap (but cool) rack-mount bucket brigade delays and an Electro-Harmonix Memory Man on my pedal board, but the Del-Verb is all these effects in one plus more. The pedal’s face is uncongested: six control knobs for effects, vibe, and parallel mixing, with two toggles for delay and reverb type, and two footswitches for Delay (in/out) and Reverb/Tap. Additionally, the UAFX Control app again opens huge customization opportunities with this pedal. Adding separate delay and reverb effect sends in mixing is common practice. With the Del-Verb, this becomes a one-and-done affair. The ability to craft a customized ambient vibe for a song or project with one device is giving me straight-up instant Lana “Del” Rey production vibes – totally customizable with lush ambience for days. Give me a rack version of this one, please!”

Lastly, I've been using the Golden Reverberator, Brigade Chorus & Vibrato, and Orion Tape Echo pedals around Panoramic for the past few months. The Golden Reverberator has been especially useful, not just with the other UAFX amp pedals (as mentioned above) but also with older amps that don't have a built-in spring reverb, like our vintage Silvertone Model 1482 and Emery Sound Superbaby [Tape Op #21]. We also have several one-off, hand-wired tube amps that Bryce Gonzales of Highland Dynamics made for us built in old, discarded chassis that sound amazing, and they don't have reverbs either. We do have an analog Peavey Valverb tube spring reverb we can use, but the Golden Reverberator sounds better and is more versatile. The spring model is the obvious choice when running through an amp, and it sounds awesome. Adding an EMT plate or Lexicon 224 reverb to a vintage tube amp may be blasphemy to some, but it's fun and can open up all sorts of new sonic potential with our tube amps. The Brigade Chorus & Vibrato is a small format pedal that models the Roland/Boss Chorus Ensemble stompbox, and it does that very well. Rich and full for when you want that lush, chorused guitar sound. My only caveat here is that after reading Larry's take on the Astra Modulation Machine pedal and its stereo Chorus effect, I'd likely opt for the Astra in a recording scenario over the mono Brigade Chorus & Vibrato – although the smaller Brigade would be a better single-purpose choice for a live rig.

As much as the bigger pedals have very deep functionality, I do love the simplicity and mono-tasking functionality of the smaller pedals, and of this entire line – if I could only pick one – the small format Orion Tape Echo pedal might be it. It mimics the Echoplex-type tape echoes – my favorite delay from listening to way too much Led Zeppelin and Jimmy Page in my formative years. The compact Orion has the expected controls for Delay time, Mix, and Feedback, plus Rec (record) Level – but it also has three settings for Tape (Mint, Worn, and Old) as well as a Wonk control that introduces wow and flutter. I own a tube Echoplex-type tape delay, and it sounds fantastic when it works, but right now, it's not working very well. I'll echo Scott's comments above about how hard it is to keep a real tape delay up to par, whereas the Orion always works! All the controls are smooth with no "zipper" noise, and it's totally easy to use it in real-time to make fucked up, out-of-control feedback and pitch shift effects. This little pedal sounds so good and is so easy to hook up and use that I think it's time to sell my real tape echo. Look for it on <reverb.com>.


In the past two years, the UAFX Pedal line has turned into a complete ecosystem of amp tones and effects that sound excellent, prove reliable, and are easy to use. Whether you need a complete signal path from scratch or are just looking for a particular effect, any one of these pedals will be a long-lasting investment into your rig or studio. And, as a final postscript, I want to commend UA for the packaging on these pedals. Packaging for audio gear runs the gamut from huge amounts of high-density foam that fills our oceans with microplastics to overly clever high end packaging that immediately gets tossed (à la Apple). The UAFX boxes are primarily cardboard, with no – or very minimal – foam, and they for make nice re-usable cases if you want to keep them organized on a bookshelf. What I also really liked was that each pedal has a short text inside each box that serves no practical purpose but creates a very nice aesthetic touch. The Orion Tape Echo, has this: “Orion stood on the corner of Mintaka, Alnilam and Alnita looking for the exact spot where tape bends time.” The Golden Reverberator has this text: “Rise like the sun, come bathe in her endless reflections. For even the shadows know you remain forever, golden.” And on that note, I shall set down my scribe and make my way forth to my studio abode, evoking sounds and tones that send out endless textures of joy.

Tape Op is a bi-monthly magazine devoted to the art of record making.

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