Fender Parts Vibroverb AB763 1x15 Combo w/ JBL D130F 1968, Black

One crucial step was sourcing the period-correct JBL D130F, which is intrinsic to the Vibroverb sound. It’s even fitted with a convincing Vibroverb control plate on the front. To the untrained eye, this presents as a believable mid-’60s Vibroverb, making you wonder whether this was done for the sake of craft or deception. Because the original output transformer would have been designed for a 2-ohm load, it was replaced with a 1968 Twin Reverb transformer, which matches the impedance requirements of a single 8-ohm 15" speaker while still pairing properly with the 2x6L6 output section. The added iron gives the amp a commanding sonic footprint, with excellent headroom and low-end response.

Internally, a handful of components have been updated to modern carbon comp equivalents, along with some metal-film plate resistors on the normal channel. Fortunately, the original Blue Molded Ajax caps remain in the tone stack (with a .047uf value in place of the Super’s .022uf), preserving the core Blackface character. It also has modern electrolytic caps, so it should be good on servicing for quite some time. See circuit photos for further details.

Intent aside, this is an excellent-sounding amp that has clearly surpassed the sum of its parts, becoming something entirely its own. Regardless of its origins, it looks and performs the part convincingly—essentially functioning as a player-grade AB763 Vibroverb that's half the cost of an original!