"With this amp, Dave Davies wouldn't have had to shred his speaker to get his 'You Really Got Me' guitar tone." Mitch Colby resurrects the amp that gave Paul McCartney his start and put the Kinks on the hit parade

Considering its status as “the classic British amplifier you’ve possibly never heard of,” the Elpico AC55 combo drags some serious history in its wake. Built by Lee Products Co (L-P-Co) as an affordable general-purpose amp/PA and sold largely in British department stores from the late 1940s to ’60s, the AC55 ended up in the hands of many up-and-coming electric guitar players, including 14-year-old future Beatle Paul McCartney. An original Elpico AC55 was also largely responsible for what’s often considered the first distorted guitar in a British rock and roll recording after Dave Davies plugged into one to record his iconic track on the Kinks’ 1964 hit “You Really Got Me.”

For all that, though, it’s still a relatively limited history up against those of the Marshall, Vox, and Hiwatt amps of the ’60s and ’70s. But if anyone can revive the Elpico mystique and propel it into the 21st century in appropriately legendary form, it’s Mitch Colby. Likely the most storied American figure in British amp history, Colby worked as an engineer for Marshall’s American distributor for 32 years, helped revive the Vox brand before it was handed over to Korg, and acquired and manufactured Park amps for about 10 years until 2022, when Hiwatt purchased the brand. In addition, hand-built designs under his own name have been highly respected this past decade or more, and his meticulous re-creation of Jimmy Page’s modified Marshall Super Bass from 1969 — dubbed the Sundragon — has established a new standard for classic-rock tone.

So if there’s anyone who can take an admittedly archaic circuit from the late ’40s or ’50s and make it all it should be in the perfect world where every “catalog-amp” is its best and most tonesome self… Well, you get the picture.

As seen in the accompanying photos, the original surf-green Elpico AC55 was a much smaller combo than Colby’s revamped creation, which is covered in black vinyl in this instance. The increased size of so many essential components — cabinet, speaker, transformers and a few others — is the most obvious tell in the general bigging-up of the format. Aside from that, the Colby Elpico AC55 retains all of the most characteristic quirks of the original, which help it to sound quite unlike any other familiar vintage amp.

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As Colby tells us, “The original AC55 had lots of preamp gain with a lot of negative feedback in the output stage, a relatively unusual James tone stack, and an ultralinear power stage with a transformer with two four-ohm secondaries. In the new design I use both at all times—in parallel for the four-ohm setting and in series for 16-ohm.” The James tone stack Colby mentions is essentially a passive version of the active Baxandall stage occasionally used by Orange and Ampeg, and Dr. Z more recently, with wide-sweeping bass and treble controls.

Among his additions for increased versatility are a mid control, a master with bypass switch, independent three-way bright switches on each channel, a switch to cascade the two channels together for even more gain, and a line out with level control and switch for full or compensated response (a faux-cab voicing). Noting that the original’s third channel — Gram, for gramophone (record player) — was essentially useless for guitar, Colby has eliminated that one, while he’s revoiced the second of the original’s otherwise identical two Mic channels for greater tonal variety.

Otherwise, the Colby Elpico AC55 specs out like the classic British club tube amp, producing around 16 watts from a pair of EL84s, two 12AX7/ECC83s in the preamp, another in the phase inverter, and an EZ81 rectifier tube. The speaker is a Celestion G12H-25 Greenback, mounted to a birch-ply baffle in a solid-pine cab measuring 22 by 19 by nine inches and weighing 34 pounds. Which is to say, the Colby Elpico AC55 is a lot more amp than the original, while it stays true to its unusual and inspiring personality. It also looks fantastic in it black vinyl covering with white piping (other colors are available), with an expensive EC Collins Bluesbreaker-style pinstripe grille cloth filling the trapezoidal speaker cut-out, an echo of the original’s unique styling.

Inside, the circuit displays Colby’s proven knack for top-quality workmanship. The thick, welded aluminum chassis carries a rugged turret board handwired with top-shelf components, including Mallory coupling capacitors, MOD electrolytic caps, and a mix of carbon-comp and carbon-film resistors.

Tested with a Fender Telecaster and a Gibson ES-355, the Colby Elpico AC55 delivered lots of bark and no shortage of classic EL84 chime, but with quite a different voice than the usual British suspects. It has a somewhat thicker midrange than the Vox-inspired dual-EL84 designs that dominate this sector, though one that’s not outright “Marshally” either. There’s also an interesting combination of articulate attack backed by easy compression, which would seem to contradict each, yet are appealingly married in the amp’s playing response.

Even in Normal mode, there’s serious chunky grind when you drive the volume past noon, especially on channel two, which is thicker and slightly darker. Channel one, in contrast, is brighter and sparklier, while both deliver excellent headroom until you get their respective volume controls up past noon (in Normal mode) — all of which is impressively loud for a 16-watter when the master’s maxed.

Cobbled into a three-word takeaway, I’d call either channel “stout, yet clear,” which gives the AC55 more of a big-amp feel overall than that achieved by many other 16-watters. Flipped to Cascade mode to chain the first channel’s gain stage into the second, the AC55 becomes altogether fiercer. Not quite the Mesa/Boogie or Soldano we associate with cascading gain, but an aggressively rocky lead beastie that’s still inherently vintage-natured, and very enjoyable.

Compared to an original early ’60s AC55 that Colby sent along for testing, the re-creation has a lot more of everything, simply put, and is just a far more usable mid-sized amp for the modern player. But it does indeed retain the character of its 60-year-old forebearer, which delivers a juicy, rich, unique voice at far lesser volumes, and one that could still be very useful in front of a mic in the studio.

But would Dave Davies approve? I’d like to think so, and perhaps with Colby’s version on hand in the studio in 1964 he wouldn’t have had to go to such lengths to achieve his “You Really Got Me” signal chain. As he told me during a chat over tea and scones in a West London hotel many moons ago.

“I was getting really bored with this guitar sound — or lack of an interesting sound — and there was this radio-spares shop up the road, and they had a little green amplifier in there next to the radios, an Elpico. I got a single-edged Gillette razorblade and cut round the cone like this.” Here he indicated making slits from the center to the edge of the cone. “So it was all shredded but still on there, still intact. I played and I thought it was amazing, really freaky. I felt like an inventor! We just close-miked that in the studio, and also fed the same speaker output into the Vox AC30, which was kind of noisy but sounded good.”

You’ll need no such shenanigans with the Colby Elpico AC55. Simply engage the Cascade switch, crank it up and there’s thick, meaty tube overdrive aplenty, with nary a shredded speaker in sight. However you use it, this interesting new combo from a master of classic British tone is likely to prove extremely inspiring and surprisingly versatile, while also helping you stand out from the crowd sonically in the process.

SPECIFICATIONS

CONTACT colbyamps.com

PRICE $3,350 direct

CHANNELS 2

CONTROLS Volume 1, Volume 3, Bright 1, Bright 2, Treble, Middle, Bass, Master with on/off switch, Cascade switch

POWER 16 watts

TUBES Three 12AX7 preamp/PI tubes, two EL84 output tubes, EZ81 rectifier tube

EXTRAS Dual speaker outs with switch for 4Ω/8Ω or 16Ω, ¼" direct out with level control and switch for Full or Compensated Response

SIZE 22"x19"x9"

WEIGHT 34 lbs

ASSEMBLED IN USA

KUDOS A clever and extremely well-built re-creation of an under-recognized classic, and surprisingly versatile in its own right.

CONCERNS Its high cost might limit its reach, but that’s somewhat inevitable for an amp of this quality.