The amplifier chasis was housed in the bottom of an open backed cabinet with the two control knobs mounted on the amplifiers faceplate.
The Thunderbolt came covered in Supros traditional blue ‘rhino hide’ tolex with horizontally striped grey grill cloth. In 1967, black tolex replaced the blue rhino hide to keep more in line with Fender.
Not only did the speaker and tubes distort, the baffle board that held the massive speaker fluttered.
But bass players were not at all satisfied with this Supro amp.
However, as a guitar amp, the Thunderbolt was a something else. That raw tube distortion combined with the heavy bottom of the Jensen 15 sounded huge.
Outside the amplifier was different in appearance, sporting dark brown grill cloth with a fancy logo. On the inside was the same Thunderbolt amplifier.
By 1967, Valco merged with Kay. However, this was end of the line for Valco. The merged company went out of business in 1968.
|This is an older Zinky amp|
In the mid 2000’s former Fender amp designer, Bruce Zinky left that organization and started his own company.
His first hit was a small practice amp called The Smokey, which still is available with a plastic housing or housed in and empty cardboard cigarette pack with a tiny speaker poking out of the center.
Zinky went on to produce high quality boutique amplifiers under his name. Recently Zinky acquired the rights to the Supro name and is now producing high quality updated replicas of former Supro amplifiers.
All of the new amps are made in the USA by Absara Audio. The project designer is David Koltai, with circuits curated by Bruce Zinky.
The new amps were just exhibited at the Summer NAMM and feature not just an updated version of the original S6420 Thunderbolt, but a hotrod version that is designated the S6420+ Thunderbolt(+).
The other new Supro amp include the 1624T DualTone with twin 12” Supro speakers rated at 24 watts, the 1690T Coronado with twin 10” Supro speakers and a pair of 6L6 power tubes pumpling out 35 watts and the S6450R Thunderstorm, which comes with twin parallel channels, a 3 way tone stack, twin 6L6 power tubes and 3 way rectifier switching options; 35 watt, 45 watts and 60 watts.