1965 Supro Thunderbolt S6420 Vintage 1x15 Tube Amp, Near-Mint w/ Jensen C15PS & USA Tube Set

Up for sale, a 1965 Supro Thunderbolt model S6420 in near-mint condition and in perfect working order, recently serviced and complete with a full vintage tube set. 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 C15PS 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 features original transformers and CTS pots which date to ‘65, with a clean recap of the power supply with F&Ts and a few modern premium Jupiter tubular capacitors in the preamp. 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 USA Sylvania 6L6GC power tubes and a pair of RCAs in the preamp. The speaker is the original Jensen C15PS ceramic magnet 15" driver, and the date stamp on the edge of the frame is from the 39th week of '65.

The chassis is exceedingly clean, and while the relatively thin chrome plating and lightly applied black silkscreening often wear easily, that’s not the case here. The cabinet features the original blue/gray textured covering and silver sparkle grillcloth, with sparingly little wear to report. The original handle and small raised “Supro” badge are also present.