Universal Audio Lion ’68 Super Lead Amp

UA add emulations of three iconic Marshall amps to their acclaimed UAFX amp pedal line‑up.

When Universal Audio launched their amp‑ and speaker‑emulation pedals in 2022 with a Vox and two flavours of Fender, there was a notable omission: surely there had to be a Marshall — the iconic sound of rock guitar — in the works? Well, it’s here now, and it is stunningly good! The Lion ’68 Super Lead Amp, to give it its full title, models three flavours of 100W Marshall valve amps: the classic Super Lead, a Super Bass (not just for bass players!) and a Super Lead running on a reduced mains voltage (using a Variac) for extra distortion. Each can be paired with one of six speaker‑cab and dual‑miking combinations, with a further option of ‘no cab’ for use with an external speaker‑sim or, indeed, with a real speaker via a power amp.

The form factor remains the same as for the other amp modellers, with six control knobs and two footswitches. Audio is stereo in and out on unbalanced jacks, and an external PSU capable of at least 400mA is needed; like UA’s other large‑format pedals, this is a power‑hungry, dual‑processor device. Once again, a USB‑C connector is used for registering the pedal and firmware updates (you get three additional speaker cabs when you register), and deeper editing and preset handling are only possible using a mobile app that connects over Bluetooth.

I’ve owned and used most of the iconic Marshall models over the years, but ‘the one’ for me, which saw me through countless gigs in the ’70s and ’80s, was a 100W Super Lead, and that just happens to be what most of the Lion ’68 is based on. Not that all 100W Super Leads are the same: they are very much not! Despite being a relatively simple design, the circuit received a number of revisions, components were changed, their values drifted, and indeed their original values varied just enough to make a difference given the component tolerances of the era. By 1968, the Super Lead model featured a massive 5000pF ‘bright’ capacitor as a fixed element (ie. not switchable like on most Fender amps). It’s a big part of what made a Super Lead sound like a Super Lead, provided you could turn the volume up far enough to mitigate its effect — say, somewhere above six, by which time it was very, very loud! Anywhere much below that, it would make the amp sound unusably thin and harsh. It was a common and easy mod, even when these amps were new, to swap out the 5000pF cap for a smaller value, and UA have taken the pragmatic option of pre‑modding their virtual Super Lead with a 100pF bright cap, a value used in some earlier Marshalls. Enough, but not too much, though there’s the option also to disable the bright cap altogether in the app. The Super Bass model has no bright cap, and for many players it was a preferable amp for cleaner sounds, or to use with the harsher‑sounding fuzz and...