The Universal Audio UAFX Lion '68 Super Lead Amp is a digital amp-in-a-box pedal that emulates the tone of a classic Marshall Plexi amp1. Announced on 28 November 2023 and offered for preorder at launch1, it is the fourth UAFX amp modeling pedal from Universal Audio, following the Ruby '63, Woodrow '55 and Dream '652. Where those earlier pedals covered other amp families, the Lion is the line's take on the overdrive and distortion character of late-sixties Marshall heads.
Because it is a modeling amp pedal rather than a conventional overdrive circuit, it can run straight to a PA, DAW or FRFR speaker2. Sweetwater's description, quoted by Delicious Audio, called it "one of the most realistic emulations of the legendary Super Lead we've ever heard here at Sweetwater"1.
Three amp models: Super Lead, Super Bass and Brown
The Lion carries three discrete amp models, emulating 1968 examples of both amps plus a third mode called Brown2. Guitar.com's reviewer described them as "three discrete amps modelled here, organised in order of hairiness," with the Super Bass as the lowest-gain of the three3.
| Model | What it is | What reviewers said |
|---|---|---|
| '68 Super Bass | 100-watt Super Bass model | MusicRadar found its high headroom makes it "an excellent platform for clean tones and drive pedals," and a good transition option for players coming from Fender combos2 |
| '68 Super Lead | Emulation of the 1968 Super Lead | Guitar.com called it "the most versatile" of the three32 |
| Brown | A 100-watt Super Lead with Variac'd power, circuit tweak and EQ'd boost2 | MusicRadar found it "very much a hot-rodded take as promised"2 |
The Super Lead models also carry a circuit detail players of the real amps will recognize: Universal Audio modified the stock bright cap to 100 pF, the value used in the earlier JTM 45 amp, against the original 5000 pF value, which the company describes as giving "jangly highs without the harshness"2. Each amp mode is matched to one of three cab/mic/speaker settings, which Guitar Pedal X lists as GB25, GB30 and JB|GB14.
The controls and footswitches
The control panel follows the layout of the amps it models, with a few pedal-specific additions24:
| Control | What it does |
|---|---|
| Volume I | First volume control, as on the amp2 |
| Volume II | Second volume control, as on the amp4 |
| Output | Master output level2 |
| Bass | Bass control; doubles as Room control in Alt mode2 |
| Middle | Middle control; doubles as Presence control in Alt mode2 |
| Treble | Treble control; doubles as Boost control in Alt mode2 |
| Cab mini toggle | Selects the cab IR setting2 |
| Options mini toggle | Selects Amp control, Alt control or Store preset mode2 |
| Model mini toggle | Selects Bass, Lead or Brown amp model4 |
The dual-function knobs work through the Options toggle: in Amp mode the knobs behave as amp controls, and in Alt mode they access the secondary functions such as Room, Presence and Boost2.
Input routing offers Low, High and Jump options, mirroring the input channels of the real amp2. The pedal's own boost is based on the Echoplex preamp pairing favored by Jimmy Page, and it has a darker tonality2. MusicRadar's reviewer found that darker character "worked really well with my brighter pickups, but it might not suit others' tastes"2.
There are two footswitches: a bypass/boost switch and a preset footswitch2. The boost can be assigned to the second footswitch, or that switch can instead trigger a whole second Lion amp/cab pairing, effectively giving you two complete rigs in one pedal2. Presets are saved and accessed with the right footswitch1, and the UAFX app adds access to artist tones and custom presets1.
Firmware 2.0, released in November 2025, added MIDI functionality across compatible UAFX pedals, allowing effects tweaks and parameter presets with a MIDI host. It also lets players store four presets on the pedal itself and switch between them on the hardware2.
Routing, power and connections
The Lion has stereo and mono inputs and outputs, with USB-C for firmware updates2. The stereo routing can be switched to become an FX loop via the UAFX app, which Delicious Audio flagged as a point of flexibility for pedalboard builders1. The pedal is Bluetooth-compatible for access to Universal Audio's UAFX app1.
Power comes from a 9V DC pedalboard isolated power supply with a 400mA draw2.
At 400mA, the Lion needs a proper isolated pedalboard supply, not a battery or a shared daisy chain output. Plan a dedicated 9V DC output when building your board around it2.
Where it came from
The Lion was announced on 28 November 2023 and made available for preorder the same day1. It arrived as the fourth UAFX amp modeling pedal, after the Ruby '63, Woodrow '55 and Dream '65, a lineage MusicRadar noted meant "expectations are high"2.
Behind the modeling work is UAFX senior product manager and sound designer James Santiago, whom MusicRadar describes as "an amp romantic and analyst, spending months searching for stock reference units" with the team before the project could begin2. The pedal also ships with factory amp presets from Plexi icons, including song-specific Kossoff, Van Halen, Eric Johnson, AC/DC and Jimmy Page sounds2.
Universal Audio has since extended the UAFX amp pedal line with the UAFX Enigmatic '82 Overdrive Special.
What reviewers said
MusicRadar's review was strongly positive on the core sound, calling the Lion '68's tones "the best modelled Plexi tones I've heard in the digital realm"2:
"The Lion '68 offers the best modelled Plexi tones I've heard in the digital realm"
The same reviewer highlighted the pedal's dynamic response, noting it reacts strikingly well to guitar volume controls even at lower, house-friendly volumes2. The overall verdict called it "an incredibly detailed deep-dive into the Plexi experience with the versatility to shine at home and away," and the closest the reviewer had heard a Marshall-in-a-box get2. The one real downside flagged was the absence of a headphone output, which the reviewer said "undermines the concept somewhat for me"2.
Guitar.com's take was more conditional: "If you know what you want, and what you want is a Marshall in UAFX amp pedal form, then the Lion is for you"3. GuitarPlayer has described it as "the ferocious Lion '68 Super Lead Amp Marshall Plexi modeler"5.
Videos
Andertons Music Co
Sweetwater
Sweetwater
Questions
Does the UAFX Lion have a headphone output?
No. MusicRadar's review called the lack of a headphone output the only real downside, saying it undermines the pedal's flexibility somewhat. If silent practice matters to you, this is the main thing to weigh before buying.
Can the Lion '68 run in stereo?
Yes. The pedal has stereo and mono inputs and outputs, and the stereo routing can be switched to serve as an FX loop through the UAFX app. That gives you either a wide stereo rig or a loop for time-based effects.
Does the UAFX Lion have MIDI?
Yes, since firmware 2.0 in November 2025. The update added MIDI functionality across compatible UAFX pedals, allowing effects tweaks and parameter presets with a MIDI host, plus four presets switchable on the hardware itself.
Can I use the Lion '68 into a power amp or FX return?
Yes. It is a modelling amp pedal that can run straight to a PA, DAW or FRFR speaker, and its cab IR section can be handled via a mini toggle. It also works as a front-end into a normal amp, with the app offering routing options.
What is the Brown mode on the Lion '68?
It is the third amp model, described as a 100-watt Super Lead with Variac'd power, a circuit tweak and an EQ'd boost. MusicRadar's reviewer found it very much a hot-rodded take, the highest-gain of the three modes.
Is the UAFX Lion true bypass?
No. It uses a high-quality buffered bypass with analog dry-through, so your dry signal stays in the analog domain when the pedal is bypassed. It is a buffer-equipped pedal rather than a true-bypass design.
Sources (5)
- Universal Audio UAFX Lion Plexi Overdrive, Delicious Audio, 2023-11-28
- Universal Audio UAFX Lion '68 Super Lead Amp pedal review, MusicRadar, 2023-12-12
- UAFX Lion review: UA’s most raucous pedal yet delivers the goods, Guitar.com, 2024-01-05
- Guitar Pedal X, Guitar Pedal X, 2023-12-17
- UAFX Enigmatic '82 Overdrive Special Amp pedal reviewed, GuitarPlayer (www.guitarplayer.com), 2025-02-26
