In this TECH TIP Fender clears up the confusion over tremolo and vibrato.

Let's call time out for a minute here to address an age-old quandary in the guitar and amp world, namely, the use of the terms tremolo and vibrato.

These two words are often used interchangeably, but in fact they aren't the same thing. Although they're sometimes perceived as somewhat similar effects, tremolo and vibrato are two separate and different physical and acoustic concepts, and people sometimes say one when they actually mean the other.

Nonetheless, tremolo and vibrato continue to be used interchangeably. The main reason why is that for decades, guitar and amp makers-Fender included-have labeled the mechanisms of vibrato-equipped guitars as tremolo systems and, more often than not, labeled amps built with tremolo circuits as vibrato-equipped devices. More about this shortly, but first let's correctly describe the terms.

Vibrato is a pulsating sound effect produced by slight and rapid changes in the pitch (frequency) of a note. It has been used for centuries as a technique for adding expression and coloration to music, and it is characterized by two parameters, depth (the amount of pitch variation) and speed (how quickly the pitch is varied).

Tremolo, on the other hand, is a trembling or "shuddering" effect produced by slight and rapid changes in the volume (amplitude) of a note. It too has existed for hundreds of years as a musical technique, but for our purposes it is a much more recent technical innovation used in amplifier design. It is characterized by similarly labeled parameters, including depth (the amount of volume variation) and speed (how quickly fluctuations in volume are varied; also variously labeled as rate or intensity).

In short: Vibrato deals with change in pitch. Tremolo deals with change in volume.

True vibrato is most often achieved either manually or mechanically. Manual vibrato ("hand vibrato" or "finger vibrato") is a fingerboard technique in which the fretting hand bends the string up and down smoothly and regularly, thus producing the slight alterations in pitch by which vibrato is correctly defined. Since the mid-20th century, many electric guitars have been equipped with mechanically operated vibrato systems, most often in the form of a rocking bridge assembly operated by a hand lever.

Therein lies the confusion. When Fender introduced the Stratocaster guitar in 1954, the guitar was equipped with an ingenious mechanical bridge mechanism designed to efficiently enable string bends from subtle to swooping while maintaining accurate intonation. This was in actuality a vibrato system, but Fender billed it, in a non-standard use of the term, as a synchronized tremolo system. Indeed, one of the very first 1954 advertisements for the Stratocaster led with the headline "Tremolo Action …" (see photo).

Ever since, Fender and guitar players worldwide have referred to the mechanical vibrato systems of the Stratocaster, other Fender guitars and electric guitars by a variety of other manufacturers, as tremolo systems. The common name for the lever arm that operates these systems has long since passed into the guitar lexicon as the trem arm, and other parts are similarly labeled (i.e. trem block, trem springs, etc.). Make no mistake, however-the phenomenon these devices produce is vibrato.

Further complicating matters, many guitar amps that were and still are marketed as offering built-in vibrato in reality offer built-in tremolo.

Amplifiers offering tremolo-again, slight rapid changes in volume-have been around since the late 1940s. Fender introduced its first tremolo-equipped guitar amp, the Tremolux, in summer 1955 (it was in fact the first Fender amp with a built-in effect; basically the Deluxe model with a tremolo circuit). In this instance, the amp was accurately named and advertised-the Tremolux offered tremolo.

The second Fender amp with a built-in effect, the Vibrolux, was introduced in 1956. It too offered a tremolo circuit, but it was billed as offering vibrato. Perhaps authors John Teagle and John Sprung put it best when they noted in Fender Amps: The First Fifty Years that "The Vibrolux supposedly introduced vibrato (pitch modulation) to Fender amps, but in reality this was just another variation on the tremolo already found in the Tremolux."

Thus began a long tradition of describing tremolo-equipped Fender amps as vibrato-equipped amps. Even today, currently available Fender amps such as the '65 Super Reverb, '65 Twin Reverb, '65 Twin Custom 15, '65 Deluxe Reverb and Custom Vibrolux Reverb are described-often right there on their control panels-as offering vibrato when in fact what they actually produce is tremolo. Again, as Teagle and Sprung note, "In fact no Fender amp has ever had true pitch-bending vibrato, regardless of catalog hype to the contrary."

Confused? Don't be. Just remember that vibrato means changes in pitch, and that tremolo means changes in volume. And that in effect, Fender simply reversed the terms, so that its "tremolo-equipped" guitars actually have vibrato, and its "vibrato-equipped" amps actually have tremolo.

Original Article