Fender’s V-Front 5B4 Super-Amp

Wonder Wedge
Fender’s V-Front 5B4 Super-Amp
1952 Fender 5B4 Super Amp
• Preamp tubes: three 6SC7
• Output tubes: two 6L6G
• Rectifier: 5U4G
• Controls: Mic. Vol., Inst. Vol., Tone
• Speaker: two replacement Eminence 10ALP (originally two Jensens)
• Output: approximately 25 watts RMS

Though all tweed Fender amps of the late ’40s and ’50s are lauded and lusted after, the V-front Super might be the most iconic – and elusive. So, when a golden-era combo like this was also the compatriot of a player known for his tone, it’s got to be special.

Aside from their undeniably cool and rare appearance as the only Fenders ever offered with wedge-fronted cabinets (having evolved from the early Dual Professional), early Supers are known to sound astoundingly good when kept in decent condition, and are much more versatile than the brown-sounding electrified suitcase one might expect when plugging in. As such, the model has remained highly desirable for its stellar sound, though the equally stellar collectability makes it difficult for mere players to get their hands on one these days, while also making them a tempting fund-raiser for those who already own them.

Such was the case when acclaimed former Hall & Oates/Bob Dylan guitarist and longtime “Saturday Night Live” bandleader G.E. Smith sold this V-front ’52 Super (along with a bundle of other amps) to a Seattle dealer in 2017. The amp then changed hands again, making it available for a closer look.

The individual baffles for each speaker are mounted at angles to each other. The 10″ Alnicos are Eminence replacements.

Arriving just after the founding of the Fender company, the V-front combo presented a number of innovations that helped put its maker on the radar of professional players. Unveiled in late ’46 or early ’47, the Dual Professional was the first Fender that:
• was housed in a finger-jointed cabinet
• offered easy access to the inside of the chassis through a removable back panel
• was covered in tweed (initially a whiter, more linen-like variety)
• carried a tube chart
• was also the world’s first production guitar amp with two speakers.

The final feature spurred Fender to design the unique “split V” baffle for the combo’s front panels, with two slices of plywood projecting the sound from their respective 10″ Jensen Alnico speakers at angles from each other. The effort made for more-complicated cabinet construction, since the top and bottom panels were shaped to match the wedge.

In the fall of 1947, the short-lived Dual Professional was renamed the Super-Amp, but was otherwise similar, barring the circuit evolution wrought upon all Fenders of the era. Some changes, though, were insignificant. The Dual Professional was born with two eight-pin 6SJ7 pentode preamp tubes plus a 6N7 phase inverter, but not long after the name change to Super, the circuit was reworked to use three eight-pin 6SC7 dual-triodes. Pentode preamps can be microphonic, especially when used in rattling, vibrating guitar amps, and even more so in the larger/early eight-pin formats. So, the change to dual-triodes makes sense from that perspective, but it also introduced two more gain stages to the circuit, which could be used independently for their respective inputs.

This Super sports the familiar early-Fender control complement of two Volumes and one Tone. All four inputs are electronically identical within the circuit.

Despite other points of “modernization,” the Super’s circa-’52 circuit remains archaic by today’s standards – or even by the standards of Fender designs to come in just a year or two. One oddity that appears extremely peculiar to those familiar with slightly later circuits is the use of grid-leak bias on the input tubes. To accomplish this, each of the amp’s four individual inputs (two each for Microphone and Instruments, though all are identical inside) run through a .05-microfarad coupling capacitor on their way to the input (the grid) of each of the tube’s two triodes, with a 5-meg resistor coupled between the tube’s grid connection and ground. The cap blocks DC voltage from making its way back to the input jack, while the resistor sets the negative current at the grid, which determines the tube’s bias. It’s a very different setup than the familiar cathode-bias arrangement of almost all notable guitar amps post-’53, and results in a different-sounding preamp that can sometimes be heard as “thick and creamy,” but can also be a little woolly and prone to easier overload.

The tube chart remains in good condition, and declares both its 5B4 circuit and tube complement that gets the job done.

For all that, though, early Supers can sound surprisingly viable in a range of situations. Rather than the woofy, muddy, midrange slop you might expect from a 70-year-old amp, they can be delightfully crisp, articulate, and laden with character – at least when reined in short of significant distortion. Pushed harder, expect succulent blues and rock-and-roll tones with plenty of compression and a delectable touch sensitivity.

The output stage carries a pair of 6L6G tubes that are cathode-biased, generating only around 25 watts RMS at best. That said, the most legendary of tweed Supers, the narrow-panel 5F4 of the late ’50s, typically put out 28 to 35 watts despite often being tossed into the 45-watt camp in colloquial conversation. So this isn’t an especially “quiet” combo by any means.

As is often the case with amps of this vintage, maintenance has been done to keep things ticking. In this case, signal and filter capacitors have been replaced.

Amps this old require regular maintenance to keep them functioning and sounding their best, and both coupling and electrolytic capacitors from this era can be particularly leaky, requiring replacement. As such, new Mallory signal caps and F&T electrolytics have been installed throughout this Super to keep it singing, though the original resistors have been retained in almost all positions other than the power stage. The amp also sports its original transformers. Originally mounted on one of the speakers, the output transformer has been relocated to the back of the chassis, a sensible move alongside the replacement of the original speakers with popular Eminence 10″ Alnico units from the mid ’90s.

In all respects, this ’52 Super remains a prime example of its breed – and one of the most-desirable Fender combos ever created.

This article originally appeared in VG’s November 2022 issue. All copyrights are by the author and Vintage Guitar magazine. Unauthorized replication or use is strictly prohibited.

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