J&J Virzi “Tone Producer”


The "Virzi" Violin, ca 1920 The “Virzi” violin, ca 1920

Even before the time of Antonius Stradivarius, Joseph Guarnarius, and Nicholas Amati, Italy began to earn its well deserved reputation as the breeding ground for luthierie giants. Further south, on the island of Sicily, in the village of Palermo, Giuseppe Virzi Sr. continued the heritage of the family-owned violin and pipe organ repair business. As is the European tradition for offspring to inherit and assume the craft of their parents, sons Joseph and John Virzi seized the opportunity, but took their family’s heritage to the New World in search of fame and fortune.

In the beginning of the 20th Century, Joseph and John moved to the United States, took up residence on upper East Side of Manhattan (124th Street), and sought to take advantage of the surge in popularity of acoustic string music. Boasting a line of fine violins, violas, and bass viols, the Virzis opened a sales office at 503 Fifth Avenue in New York City.

While the economic opportunities of the U.S. market offered great potential for violins from Italy — a natural connection for the two Virzi brothers — it is interesting to note that the Virzis instead turned to Heron-Allen and Alberto Bachman of Marchneukirche, Germany to produce their instrument line.

By the late 1920’s, their offerings featured six models; “Virzi Type,” “Type Virzi,” “Type Maestro,” “Type Master,” “Type Cremona,” and the “Semi-Strad” Type. The leading model had a retail price of $250 (a price comparable to Gibson’s F5 mandolin of that period). In addition to Virzi’s line of instruments, the company’s offerings included a full complement of strings, cases, bows, accessories, and the service of installing a unique “tone producer” in violins (at first) and then in a wide range of stringed acoustic instruments.

J&J Virzi Honor J&J Virzi was awarded the highest honors at the International Congress of Instrument Makers, in Rome (1925) for its breakthrough development of the “Tone Producer.”


The Virzi Patent

Giuseppe Virzi  was awarded U.S. Patent No.1,412,584 on April 11, 1922. The patent, which was applied for in 1920, was very simple in nature and describes only the fact that one or more soundboards could be supported inside such instruments as guitars and violins. It further describes that the plates could be attached to each other with dowels, and that the plates could be arch shaped.

Virzi's PatentVirzi’s patent was issued on April 11, 1922. The f-holes in the right-hand drawing are merely for reference – the violin drawing is actually as seen through the backboard, with the Tone Producer affixed to the violin’s bass bar. In the lower end-view drawing, the curvature of the patented plates, can be seen. The location of the Tone Producer plates in viol-family instruments would be the same for all instruments in this family (bass, viola, etc.).

It is not unusual for a patent to be somewhat dissimilar from a product that emanates from its claims, and this was the case with the Virzi Tone Producer. Rather than multiple plates, as described in the patent, the Virzi Tone Producers in common production were single plates. And rather than being arched, they were flat plates.


Virzi Patent Drawing While Virzi might have experimented with multiple Tone Producer plates (and there may be some instruments in existence with multiple plates), the production Virzi instruments had only a single plate as did the Tone Producers that were installed in Gibson’s instruments.

Of further interest is that the claims of the patent do not boast any of the contributions to tone generated by the plates, just that they are suspended inside the instrument.

The Tone Producer

A leading attribute of the Virzi violins was the addition of a secondary soundboard or “tone plate” (they also called it “Tone Amplifier,” and “Tone Producer”) which was affixed to the soundboard by either two or three feet (depending on type of instrument). The Tone Producer was a thin disk of particularly wide-grain spruce which was intended to be highly sensitive to the amplification of vibrations sent to its surface via the feet. The plate was rendered additionally delicate by the two f-hole-like slits which were to make the outer wings of the plate as free and limber as possible. The key to the functionality of the Tone Producer was in supporting the plate from it’s center as opposed to supporting it around its rim.

What’s behind their discovery

From an acoustic standpoint, plates (soundboards, backboards) secured along the rim vibrate in specific patterns and modes that are unlike plates secured in their center. Since the Tone Amplifier was held in the center, rather than by the rim, it was free to vibrate in different modes from the way the rim-secured soundboard and backboard could vibrate, and thus it emitted an entirely different series of overtones or “partials.” Additionally, the partials, especially the higher numbered partials, are more easily emitted from this thin, airy disk than from a more rigid soundboard.

Partials are subsets of vibrational modes and there is a specific order to their frequency, volume, and vibrational pattern. As it relates to a musical string, the lowest note at which a string vibrates is called the “fundamental.” This occurs when the string vibrates in one complete motion. When the string vibrates in halves (such as when we play a string and touch it lightly at the 12th fret; half it length) it is forced to vibrate in halves. This is referred to as the 2nd partial and the sound we hear is called a “harmonic.” On a given musical string, we can detect up to 18 or 20 partials until we either go above the human audible range (approximately 18,000 Hz or we are unable to define a partial.

We can force a string to vibrate in partials by touching it at certain point along its length, after it is played, which causes a null and forces the string to vibrate in segments. The sound we hear is called a “harmonic,”

Like strings, plates or soundboards have vibrational modes of their own. And, these modes are determined, in part, by whether the plate is secured along its rim or at it’s center. The Tone Producer provided this added and unique feature of enabling the amplification of different partial modes.

While Virzi also referred to its Tone Producer as a “Tone Amplifier,” the disk, suspended inside the instrument, had no affect on the compression or rarefaction emitted from the instrument and thus it had no affect on its amplitude (loudness). In fact, since the disk was attached to the soundboard it took additional energy to drive it — an issue which was not a problem for the violinist’s powerful bow, but proved to be a complaint for the mandolinist’s pick. The reference to the word Amplifier suggested that the disk would enhance the quality of the overtone series and make them more audible.

Tone Amplifier All Virzi violin models featured the “Tone Amplifier” which was affixed to the bass bar via two feet. In violins, viols, and bass viols, the Tone Amplifier was a singular, long elliptical disk.

In addition to installing the Tone Producer in their own violins, Virzi provided a service of installing Tone Producers in non-Virzi violins and their work attracted the attention of Lloyd Loar.

Loar’s personal viola was a full-size 1875 August Diehl which he had outfitted with a Virzi Tone Producer in 1922 (see label below). Virzi’s catalog featured a letter from Loar in which he attests to his viola’s improved tone:

Lloy Loar Comments regarding Virzi Numerous world renowned musicians received the honor of a cameo in the 1929 Virzi catalog, but a full page was dedicated to Lloyd Loar’s comments on the attributes of the Virzi Tone Producer in his Diehl viola.

“I have thoroughly tested and inspected my viola in which you recently installed your Tone Producer. It pleases me greatly. In my opinion, you have contributed one of the most noteworthy improvements applicable to the construction of all string instruments of which there is any record in the last two hundred years.

This opinion is not alone based upon the sense of hearing, but is reinforced by scientific tests much more final in their testimony.

Testing the tone of my viola, I find that: previously those notes having the most pleasing tone color of any possible to the instrument under the most favorable conditions had but twelve [audible] partials or overtones. I am now able to identify fifteen and find indications of three more which are apparently too high in pitch to register definitely [to the human].

Parallel to the above and offering the evidence of hearing instead of science, my ear tells me: (1) The tone is richer and mellower. (2) It responds more easily and quickly to the bow, a suggestion of a ‘wolf’ tone at F on the G string is gone, and the tone is more powerful. (3) The pitch of the air chamber is not changed, neither is the characteristic tone color of the instrument.”

….. Lloyd Loar, M.M, Acoustic Engineer


Virzi Label The Virzi labels in Loar’s 1875 August Diehl viola are different from labels used in the Gibson Mandolins of the same period. Here two labels were applied; one says “J&J Virzi” and the other is a small Virzi company label with the date “anno 1922” hand written at the bottom. This Virzi Tone Producer is not numbered.Those in Gibson mandolins and guitars were numbered with a special Virzi label.

Loar became enamored with the idea of using the Tone Producer in fretted stringed instruments and was instrumental in licensing Virzi Tone Producers for installation (during production) in many Gibson mandolins, mandolas, and guitars.

The Virzi Tone Producer intended for mandolins, mandolas, and guitars was a round disc with two slit openings somewhat resembling f-holes. Two bridges held the Tone Producer in place. The double-footed bridge was secured behind the mandolin’s f-hole centerline and the single foot attached nearer to the tailpiece.

Virzi Plate The Virzi Tone Producers for violins were oblong-shaped and had only two “feet” compared to the Tone Producers for mandolins (left) and guitars which were round and had three locating points which were both glued and pinned in place for structural integrity. This Tone Producer came from a 1923 Gibson F5 mandolin.

All of the Tone Producers I have seen have had very wide grain (the wide grain wood being more supple than their narrow grain counterpart). It is interesting to note that most of the tone producers were not well crafted (note misshapen circle in f-hole in photo above.)

Virzi L5 Some Tone Producers found their way to Gibson’s L5 guitars (as well as being installed in other non-Gibson guitars). When used in these instruments, the plates were tear-drop shaped and attached to the soundboard with feet similar to those in the photo.

Although the Virzi Tone Producer clearly imparts warmth and tone, many of the Tone Producers in Loar-signed F-5 mandolins have been removed by musicians (or their repair persons) with the goal of achieving more power (commonly referred to as “bark”) in favor of tone (an act which Loar would have despised since the air chambers of these instruments were “tuned” with the Virzi Tone Producer in place).

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