The world of amplifiers is often divided into particular sound “camps” to describe the tonal characteristics. Blackface and Tweed are used to describe two of the classic Fender eras, while “British” is often synonymous with Marshall amplifiers, although it can also be applied to brands like HiWatt that were based on the brawny EL-34 power tube. Vox of course is Vox, but derives its roots from cathode-biased EL-84 based products (like some early Marshalls). For the purpose of this discussion, we are going address the Tweed style, and how this sound applies to some of the amps we carry from ValveTrain and Rivera.
Tweed – The Fender “Narrow Panel” Tweed era from 1955 to 1964 was really the Genesis of mass-produced guitar amplifiers. While there were other brands emerging in the late 40′s and early 50′s, Fender certainly captured the lion’s share of professional endorsements, and what became know as “tweed” amplifiers were commonly found on professional back-lines everywhere. The Tweed era lasted into the early sixties, at which time Fender addressed many of the issues that were seen as deficiencies in the their Tweed designs, ultimately evolving into the what is lovingly known as Blackface amplifiers.
In the 50′s there was no specific guitar amplifier technology, and early guitar amplifiers were essentially schematics taken from standard design handbooks. Often these handbooks were published by tube companies trying to promote their products. As such, a public address amplifier used at a factory or county fair had a lot in common design-wise with a guitar amplifier. But amplified guitar applications were a lot more demanding that just amplifying a voice (not to mention the new electric bass). As bands got louder and players looked for more volume, the limitations of early amplifier designs became apparent: Limited clean headroom and harmonic distortion at higher volume levels being the most comment ailment. The low wattage, cathode-biased pre-amps and tube rectifiers of the day were not always up to the task of delivering loud, clean volume. The earliest bands to electrify were country, swing and dance bands, and distortion was not seen as a desirable characteristic for an amplifier. This was especially true of pedal steel players, which was an important market for Fender at that time. Although the Narrow Panel Tweeds were certainly a step up from the earlier designs, the rapid growth in popularity of rock music was pushing their limits.
As new amplifier models in the 60′s became louder and cleaner — including the advent of solid state technology — some players started to miss that old compressed, warm sound of the earlier Tweed designs. Today, a good portion of the boutique amplifier market is dedicated to reproducing early Tweed designs, and many advertise which old Fender schematic version they use. You literally can’t swing a dead cat without hitting somebody’s latest version of a Champ, Bassman or Super; all in search of that warm top end, soft compression, and musical grind at higher volumes. In fact even Fender themselves has gotten in on the game with the “EC” Eric Clapton series of — you guessed it — Tweed amplifiers.
While Tweed amplifiers are great for many styles of rock music, they do have some limitations. Clean headroom at higher volumes is still a limitation, so if you are looking for that — or are content lugging around a Bassman or Tweed Twin — look elsewhere. The front end of Tweed amps also have limited gain, and can be overwhelmed by pedals. Put a strong gain or distortion pedal in front of a Tweed and you’re likely to get a mushy combination of pedal distortion and front end distortion. Tweed amps are at their best with minimal effects and sometimes the best effect is just a good guitar and cable. Lastly part of the sweetness and purity of the Tweed sound was a product of their simple circuits. Amps faithful to the Tweed heritage typically lack reverb, have minimal tone shaping capabilities, and channel switching is unheard of. Tweeds are not full-feature amplifiers, but part of their beauty lies in their ability to create very pure, organic tones with great texture. For some, that’s all that is needed.
Much of the ValveTrain line is based on the low wattage Tweed designs of the 50′s. The Trenton, Tallboy and really all of their Vintage Series (315, 416, etc) are either Tweed inspired or directly descended from specific Fender schematics. The ValveTrain line are not pure clones however, and several models have an expanded control set that provides features such as half/full power, internally connected normal and bright inputs, and master volume controls. These amplifiers retain the classic tone and feel of the original designs, but increase the flexibility of the amplifier for both gigging and recording. The Rivera amplifier lineup does not really address the Tweed ethos. Generally higher in power, with solid state rectifiers and a full complement of tone shaping options, Rivera clean tones are squarely targeted at the Blackface sound, and will addressed in a companion post on the Blackface era.