Up for sale, a 1965 Supro Thunderbolt model S6420 combo amplifier in excellent condition and in perfect working order. This perennially popular vintage tube amp was made in the USA by Valco, the parent company which also produced amps under the National, Oahu, and Gretsch banners among others.
Lightly compressed, focused, and delivering an elegant, touch-sensitive overdrive that's sonically distinct, the Thunderbolt pushes roughly 35 watts through a pair of 6L6 power tubes and a Jensen C15P speaker. For everything from clean, wooly rhythm tones to saturated tube roar further up on the volume dial, the Thunderbolt delivers a pure sound with a simple yet ingenious circuit and only two knobs for Volume and Tone.
The circuit is very original, with stock transformers that date to ‘65, and CTS pots that have visible date codes from the 16th week of 1965. The power supply features a replacement multi-section can cap, with just a couple additional modern caps inside the chassis to ensure optimal functionality. Notable for being an early example of the Thunderbolt with a rectifier tube and sweet, tube driven "sag", the amp boasts a vintage RCA 5U4 in the rectifier position, along with a matched pair of modern Sovtek 5881 (6L6GC) power tubes and a pair of JJ valves in the preamp. The speaker is the original Jensen C-15P ceramic magnet 15" driver, and the date stamp on the edge of the frame is from the 18th week of '65.
The chassis retains the majority of its black silkscreened graphics, and the chrome exhibits some areas of surface rust through the plating. The cabinet features the original blue/gray textured covering and silver sparkle grillcloth. There is some wear through the covering on the bottom enclosure edges, some light staining of the grillcloth, and sparingly little additional wear to report.