Regardless of their catalog-grade standing, Supro amps have been utilized by a number of noteworthy guitarists. For a lot of, the sturdy Thunderbolt is the popular workhorse.

It’s been a very long time since Supro amps have been any type of secret discover or hidden gem; gamers have lengthy acknowledged the eccentric splendors of sure mid-sized examples, with their thumping tremolo and gritty-but-gutsy tube tone. Additionally, reissues by the revitalized Supro firm have introduced the title again entrance and heart.

One of many ubiquitous fashions among the many lineup – and an amp usually regarded as a Supro cornerstone – the Thunderbolt arguably delivers much less of the quirky signature Supro circuit traits whereas in some way remaining in keeping with the legend.

Launched in 1964, the Thunderbolt was promoted purely as a “bass-guitar” amp, as acknowledged on the combo’s management panel. Like different low-powered early choices for the four-string, nonetheless, it has been used way more usually by guitarists who shortly found that most of the qualities contributing to an underpowered all-tube bass amp can equate to only proper with a higher-register instrument plugged in. Using atop the tone, after all, is the perpetually cool Supro styling, comprising a black “rhino hyde” overlaying, silver grillecloth with black pinstripes, and that iconic emblem with the lightning-bolt swoosh. And it’s becoming that the picture speaks to an ageless type of hip within the guitar universe.

Supro’s origins date to the times earlier than the electrical guitar and the formation of the Nationwide Resophonic guitar firm circa 1926, with its resonator guitars. Supro’s mum or dad firm, Valco, was based in ’35 by Victor Smith, Al Frost, and Louis Dopyera (the corporate title derived from the primary letters of the primary names of every, plus “co”), who had purchased the remnants of Nationwide Dobro for that goal.

Smith and Frost had been workers of Nationwide, whereas Dopyera was co-owner, having helped set up Nationwide after which Dobro resophonic guitars alongside Adolph Rickenbacker and George Beauchamp within the mid/late ’20s (Beauchamp and Rickenbacker went on to supply a few of the first business electrical guitars and amplifiers below the Rickenbacker model by the mid ’30s, as the search for loud advanced from aluminum resonator cones to tube-powered pulp paper). Only a yr after founding the corporate, Dopyera, Smith, and Frost moved Valco from Los Angeles to Chicago, which was then the hub of the musical-instrument trade in the USA. It was additionally a central location from which they may simply service the various home manufacturers that might kind the core of their clientele, together with Gretsch, Kay, Concord, Airline, Oahu, and some others.

Supro’s amplifier line of the early/mid ’60s carried trendy styling, although its circuits have been nonetheless fundamental, as was its development, with the chassis mounted within the backside of the combo cupboard with a slanted, rear-facing management panel – a format that had light from recognition a decade or extra earlier than. The ’64 catalog “boasted” of the Thunderbolt: “No frills – no fancy circuits – no further weight – simply positive high quality and clear, true bass response. For the cell Bass participant and people ‘one-night’ stands.”

Certainly, the circuit makes use of simply concerning the naked minimal of phases and parts to get sign by the preamp to the output stage. One lonely 12AX7-derived triode carries it by the Quantity and Tone potentiometers within the amp’s single channel – and a coldly-biased one at that – with half of that tube remaining unused, whereas the section inverter employs the second 12AX7. A pair of 6L6GCs generate roughly 35 watts, cathode-biased with no bypass capacitor in place, presumably to keep away from swamping the stage with unflattering low-end.

This catalog listed the amp at $179.50 – $10 greater than a Princeton Reverb made the identical yr, and we all know which one most guitarists would take right this moment! Our featured instance stays with its unique proprietor, VG reader David Figie.

“In 1964, I used to be 11 years outdated and taking part in in a band referred to as The Rising Sons, in West Allis, Wisconsin,” he mentioned. “I performed a Gibson EB-0 and my dad purchased me this Thunderbolt. It was not good for bass, so Dad purchased me a Gibson Titan.”

Many agreed, apparently, and Valco tried to firm-up the Thunderbolt’s efficiency by the last decade, including additional bracing to the baffle to attempt to assist the 15″ Jensen C15PS – and the cupboard normally – stand as much as the low-end onslaught. In ’68, they revamped the design. Even earlier than, nonetheless, guitarists had begun discovering what the inventory Thunderbolt S6420 might do – Jimi Hendrix amongst them, who toured one with Little Richard and the Isley Brothers earlier than heading to London and gaining huge solo fame.

Figie’s Thunderbolt sat unused loads longer than that, although he by no means thought to promote it.

“Often, I performed my brother’s Rickenbacker 366/12 convertible by it. In 1989, I purchased a Stratocaster and have been utilizing the Thunderbolt ever since. I changed all of the tubes; I nonetheless have all of the originals, and all the pieces else is unique. This amp sounds nice for guitar!”

Designed to get a bass sign from enter to output with minimal flubbiness or distortion, the Thunderbolt is predisposed towards a heat, wealthy, and barely woolly tone, which sounds finest when pushed to drive these 6L6GCs into a bit breakup. There’s an entire unused triode stage sitting there within the preamp’s lone 12AX7, which can be utilized so as to add one other acquire stage or an lively EQ stage, however most guitarists who dig the Thunderbolt adore it for what it does naturally. Which may not be thunderous by nature, but it surely’s a juicy, throaty, edge-of-breakup drive that epitomizes a sure breed of classic tone, and has loads to supply by itself.

This text initially appeared in VG’s April 2025 challenge. All copyrights are by the creator and Classic Guitar journal. Unauthorized replication or use is strictly prohibited.