Contributed by Mr. David Schramm, Clovis / USA
My Hauser Research Paper
The Definitive Elements of the Hermann Hauser Spanish Guitar
The Hermann Hauser Spanish guitar is one of the most copied guitars of today. Visit any hand-made guitar dealer and you will find many luthiers from around the world who build what they call a “Hauser” model. Why is it so popular? Andres Segovia called his 1937 Hauser Sr. guitar, “the guitar of our epoch.” Guitar historian Richard Brune rated the guitars of Hermann Hauser, Sr., as number two out of the top ten collectable gut strung guitars. What is it exactly that makes a guitar a “Hauser” copy? In most cases the so-called “Hauser” models emulated by other luthiers have very little in common with the Hauser original. In my research I have discovered elements of construction, aesthetic and sound that I feel define the Hauser instrument. Scholarly examinations of the Hauser guitar’ s defining elements are in order to better understand what exactly is a Hauser style guitar. Potential buyers of such a model need to be informed, so as not to be persuaded by the title “Hauser.”
To understand the development of the Hauser instrument a study of the family history is in order. Josef Hauser (1854-1939) began his career as a musical instrument maker in 1875. In the year 1898 Duke Maximilian of Bavaria awarded Josef with the Art and Science prize. This was just one of many medals and presentations that the German state awarded to Josef. Besides building musical instruments Josef was also a composer of zither music and is credited with over 400 compositions to his name.
On October 13, 1884 Josef had a son named Hermann. As a young man Hermann attended the Staatliche Geigenbauschule (State school of violin making) in Mittenwald, a tradition followed by his son and grandson. Prior to opening his own shop Hermann worked in the shop of Max Amberger who produced zithers, lutes and guitars. Hermann began work in his own shop in Munich in the year 1905. Hermann built Viennese style guitars like those of Johann George Stauffer (1778-1853) “Legnani” model. He also built zithers, lutes and multi-string “Schrammel” guitars like those of Johann George Scherzer (1843-1870), an apprentice of Stauffer’s. In 1920 a patent was issued for Hauser’s Viennese style guitar strutting pattern.
Hauser had access to two of the greatest guitarists of his time, Miguel Llobet and Andres Segovia. From 1913-14 Llobet frequently performed in Germany contributing significantly to the prestige of the guitar in that country. Hauser himself was a member of the Munich guitar society. After the First World War and into the early 1920s, Hermann Hauser filled the position of first terz guitar replacing Heinrich Albert in the Munich Guitar Quartet. During this time Hauser was able to study the instruments of Antonio Torres. It is quite possible that in 1922 Hauser was able to study a FE09 (First Epoch) Torres guitar that belonged to Miguel Llobet who acquired it in 1916. When Julian Bream visited the Hauser workshop in 1970 he recalled seeing a template of Llobet’s Torres dated 1922. The aesthetics of this instrument had a serious influence on Hauser instruments built in the Spanish pattern. Segovia’s first visit to Germany was in 1924 and during this time he heard a concert by local guitarists who were playing Hauser guitars. After examining the instruments Segovia saw the mastery and potential of Hauser if he were to build in the Spanish pattern as fixed by Torres and Ramirez. Hauser was invited to Segovia’s hotel room where he examined and measured the maestro’s 1912 Manuel Ramirez guitar. Miguel Llobet, who was also present, watched skeptically as Hauser spent 3 hours examining and measuring the instrument. Llobet lacked the enthusiasm and confidence in Hauser that Segovia had.
As early as 1929 Maestro Segovia was playing Hauser instruments built in the Spanish style. Concert programs from 1929 in New York, 1931 in Berlin and 1933 in Mexico City all indicate the guitar Segovia played as “Hauser.” It wasn’t until 1937 that Hauser built a guitar that Segovia officially accepted. That guitar became known as “the guitar of our epoch”. Segovia used this instrument for many recordings and concerts. Prior to his death in 1987, he donated his famed 1937 Hauser Sr. guitar to the Metropolitan Museum of Art in New York City.
Hermann Hauser II (1911-1988) began work in his father’s Munich workshop in 1930. In 1944 Allied bombing of Munich caused the collapse of the top two floors into the basement of the Hauser workshop. This event forced the Hauser’s to shut down the workshop. In 1946 the shop was moved to Reisbach where Hermann Hauser II continued building with his father. Like his father before him, Hauser II also attended the Staatliche Geigenbauschule in Mittenwald. Hauser II was injured during the war, which might have affected him in his later years. In 1952 Hermann Hauser had died and his son, Hermann Jr. took over the shop. He continued to build in the style of his father but experimented with different bracing patterns and dimensions. Segovia also played instruments built by Hauser II. It was around the late 1950s and early 1960s then Segovia reluctantly had to retire his 1937 instrument. According to Segovia it had “fallen ill.” At one point the 1937 Hauser Sr. guitar received a gash to the soundboard in the recording studio and was refinished by Hauser II with lacquer. Shortly after this Segovia complained about the first string having “died”. In 1966 Hauser II received the gold medal for guitar making at the International Exhibition in Welser, Austria.
Hermann Hauser III (b.1958) currently carries on the family tradition. He joined the family business in 1974. At the age of sixteen Hauser III was instructed by his father, “Hermann, you must go to another workshop to see how to make an instrument.” For about two and one half years Hauser III apprenticed at the workshop of one of his father’s friends. After this time he continued the family tradition by attending the Staatliche Geigenbauschule in Mittenwald. Hauser II and Hauser III began building independently in 1977 and in 1978 Hauser III received his first gold medal in guitar making as a “Bundessieger” or “federal winner.” His older brother Eric, who sometimes works with him, also attended the Geigenbauschule in Mittenwald and won a gold medal in guitar making.
The later two generations of Hauser’s have maintained the basic aesthetic design of the Spanish model established by Hauser Sr. After studying many Hauser guitars through photographs, books, magazines, visits to dealers, museums and collectors, I have observed several aesthetic elements that are consistent in all three generations of Hauser’s. Most of my aesthetic observations can be found in common with the instruments of Torres and Ramirez that had a strong influence on Hauser I.
One of the most obvious aesthetic elements of the Hauser Spanish guitar is the head design. Hauser Sr. used two basic head designs in his Spanish model, neither of which I have found on Hauser’s Viennese style instruments. These two head designs include the typical three-lobed AntonioTorres style head and the popular Madrid style head used by Manuel Ramirez, Santos Hernandez and Domingo Esteso. The three-lobed Torres head eventually became the design found in the majority of Hauser instruments. As of this writing I have yet to see a Hauser II or Hauser III with the Madrid style head. As with many aesthetic features of the Hauser guitar they can be traced back to Miguel Llobet’s Antonio Torres FE09 that Hauser Sr. had access to. The string ramps and lower head slots were usually kept square like those of Torres, but on page 33 of the U.K. guitar magazine“Guitar International” July 1985 issue is shown a photo of Julian Bream’s 1936 Hauser with rounded string ramps and slots. This is the only time I have seen a Hauser guitar with this treatment of the head.
Another feature of the Hauser head aesthetic is the head plate itself. In my research I have not found a Hauser with an added decorative veneer sandwiched between the head plate and the head. This is another feature that I believe is borrowed from the Torres guitar and can be found on many of the Spanish guitars from the early 20th century.
Several purfling schemes have been used for the head of the Hauser guitars, but Hauser Sr. also built the head plate with no decorative purfling strips. The head-purfling scheme used by Hauser divides the head in half down its center. It usually consists of colored and natural veneers in the following order: white-green-white, rosewood, white-green-white. This seems to be very consistent in the guitar of Hauser II and III. However Hauser Sr. when inspired to do so would add other veneer lines of various thicknesses along with some half-herringbone designs. On the 1947 guitar Hauser Sr. built for himself one can also see a mother of pearl central line that replaces the usual rosewood or dark central line.
Landstorfer made the tuning machines found on guitars by Hermann Hauser Jr. and Sr.. When he died in 1976 his engraver, Klaus Reischl bought the business from Landstorfer’s widow. Presently Hermann Hauser III almost exclusively uses the Reischl tuners. They can be found on the majority of his instruments. The Landstorfer tuning machines, because of their association with Hauser, inspired tuning machine factories to produce economical copies. One of the most popular is the Schaller brand “Hauser” style tuning machine. Today custom tuning machine makers such as David Rodgers of England and Nicolo Alessi of Italy offer custom engraved Hauser-style tuning machines.
The Hauser bridge is consistent in size and shape with the design of the Spanish masters Torres and Ramirez. In the Hauser tradition of Spanish guitar making it was the aesthetic variations of Torres that influenced their instruments. The tie block is usually treated in two different ways on a Hauser instrument, both influences of Torres. One treatment of the tie block, and most common on Hauser instruments, is to use two bone or ivory strips, approximately two millimetres square, along the leading edges. The other variant used by the Hausers is a solid overlay of the tie block made from several options either mother of pearl, bone or ivory. Occasionally found in the center of each of the wings of the bridge is a single mother of pearl dot that is about twelve to fifteen millimetres in diameter. The mother of pearl dots and tie block inlay can also be found on Llobet’s 1859 FE09 Torres guitar. A Hauser Sr. guitar from 1947, which he built for himself, features a bridge with a solid ivory tie block cap and a single mother of pearl dot on each of the wings. A 1934 Hauser Sr. guitar in the possession of Sheldon Urlik features a similar treatment of the bridge, except that mother of pearl is used for the dots and the tie block overlay. Vahdah Olcott Bickford (1885-1980) who founded the American Guitar Society in 1923 once owned this instrument. The American Guitar Society, based in Los Angeles, was the first guitar society to be founded in the United States. Another Hauser Sr. guitar with the same bridge aesthetic can be found in the collection of Russell Cleveland. The date on the label of this instrument is 1935.
In guitar making, purfling is the term used to describe the decorative veneers and lines that frame the instrument. These lines can be found on the back, sides, top, rosette and head of a guitar. All three generations of Hauser’s have used a consistent purfling scheme in their instruments with only slight variations. The most commonly used purfling scheme, which is also one of the most noticeable, is that of side purfling. This technique usually consisted of two thin white lines of either holly or maple with a thicker green dyed central line. This motif may have come from the elder Hauser’s influence of Torres and Ramirez. I have seen and photographed a 1915 Manuel Ramirez guitar featuring exactly the same side purfling treatment. This white-green-white motif was used by Hauser Jr. and continues to be used to this day by Hauser III. It was never used in the non-Spanish style Hauser models. In the 1930s Hauser also used single white line purflings and blond bindings made of maple with no side purflings in instruments such as the Llobet FE09 Torres. Close inspection reveals that not all of the green lines are consistent in their color matching. This could be due to different batches by the veneer vendor or by the Hausers themselves. Around 1940 this motive was added to the top purfling. The Hausers had two basic top purfling motives that are consistent with all three generations. The first, starting with the binding, follows the following scheme: binding, white-black-white, rosewood (or dark wood), white-black-white and two narrow black lines. After World War II we start to see the following scheme: binding, white-green-white, rosewood (or dark wood), white-green-white and two narrow black lines. Other purfling schemes have been used but the above schemes are the most common and are what I consider part of the defining aesthetic elements of the Hauser guitar.
Another point to consider are the joinery aesthetic of the side, back and tail purfling. Most modern builders will mitre the side purfling to the tail purfling at a forty-five degree angle. The Hauser’s side purfling is continuous around the perimeter. The back perimeter purfling is also continuous. It is not mitred. The back center purfling extends over the heel to form the heel cap, but is divided by the back perimeter purfling. Richard Brune’s article in the “American Lutherie” quarterly journal published by the Guild of American Lutherie titled “Segovia’s 1937 Hauser Revisited” examines this technique. Some of the features of this article include detailed measurements of the purfling and includes some detailed photos of the instrument.
Just one look at Llobet’s FE09 Torres guitar and one knows exactly where Hauser Sr. got some of his ideas for his Spanish model rosette. Some of Hauser Sr.’s rosettes match this rosette in nearly every detail. Segovia’ s 1912 Ramirez has a central tile motif that is frequently used in the work of Hauser III. One of the unique things about the rosette tiles of the Hauser guitars is that they used no end grain. Most of these central tile motifs are very basic patterns such as crosses and diamonds. It is easier to use side grain when applying basic patterns. The advantage of doing so is that the medullary rays found in the side grain will shimmer. End grain tiles would absorb the light dulling the effect. Natural woods are used except for the greens and reds. For example: for brown, various rosewoods are used; for black, ebony or a dyed veneer. White lines are usually maple or holly. A frequent motif in the outer rosette rings is the half-herringbone pattern.
I explained the historical and aesthetic elements of the Hauser Spanish guitar in the previous sections. In this last section the construction elements of the Hauser Spanish guitar will be observed. As the construction elements are discussed the reader should keep in mind that Hauser was well established as a maker of the Viennese style of guitar construction.
The linings of a guitar are used to increase the surface area of the sides so that the back and top can be glued to the sides. The early Hauser Spanish guitars used a solid quarter sawn lining onto which the back was glued. This back lining is usually made from spruce or mahogany. Both Torres and Ramirez were using kerfed linings which allowed the lining to be flexible thus easily conforming to the guitar’s shape. Until 1928 Hauser was still using solid linings for tops and back, something often found in the Viennese style guitar, but in the 1930s he started to experiment. He started to use individual blocks called “tentellones” to attach the top to the sides. As the Hauser guitar evolved variations of the lining were used. One interesting observation is that even though he used a solid bent lining in some of his instruments, specific areas were kerfed after they were glued. This would explain the uniformity of the kerfs found in the linings, especially at curved sections. Hauser Jr. experimented with linings as well. In some instruments he would use kerfed spruce lining for the tops, but he would leave one centimetre on each side of the transverse bars unkerfed. For back lining he would use mahogany that was kerfed only in the lower bout and solid in the upper bout. Hauser III on the other hand kerfed his mahogany back linings between the top and middle back braces and also in the lower bout, but the upper bout was kept solid. This seems to be something kept consistent in Hauser III’s“Segovia” model.
One of the most mysterious details of the Hauser family Spanish guitar is that all three generations did something to the fingerboard that has been kept a secret. In the area of the 12-19 frets, the bottom of the fingerboard has a one millimetre counter veneer. The Hausers seem to have experimented with different materials. In some instruments it looks like mastic or a combination of hide glue and ebony dust was used. Andrea Tacchi who restored a 1957 Hauser Jr. guitar asked Hauser III about this material. His response, “This is a secret!”. To find out more about this construction detail I contacted Hauser III. Here is what he had to say:“My new guitars have this piece under the fingerboard. This is only one thing, which a Hauser guitar has more in the construction like on other guitar. (Many small pieces make in the end a big thing). If you think only for the small piece under the fingerboard I am sure you will find the right answer. Many people in the guitar world think on this piece but not every one found the right answer. Sorry that I do not tell it exactly. I hope you understand this. This is special and I know because it is a small piece under the fingerboard. You can be sure that it has sense. There are four right answers and this has also to do with the whole construction. I am sure you found by yourself two right answers.”[sic]
After receiving this answer I became more intrigued. Other luthiers that I spoke with regarding this material mentioned that Hauser told them the same thing. Some wondered if Hauser III even knew why he used it. In my opinion I feel that it was used to counteract or slow down the different expansion and contraction rates of the hardwood ebony and the softwood spruce and cedar tops. This would help prevent cracking along the grain of the soundboard where it meets the fingerboard. This theory resolves one of the four answers, but the other three baffle me. It could also have something to do with the influence of the Viennese style instruments where the fingerboard above the soundboard does not touch.
Neck and Heel
The Hauser’s used several species of mahogany for the neck, head and heel. The most commonly used is Honduras Mahogany, but Philippine and African Mahoganies have also been used. It is interesting to notice that the use of Spanish Cedar, a common neck wood, isn’t found in any Hauser instrument. A consistent characteristic of the Hauser heel is the use of a one-piece heel instead of the common practice of stacking the heel in several layers. There are a few Hauser instruments with a one-piece neck and head with a separate solid heel. This was done when a large piece of exceptional wood was available.
One of the most distinctive features of the Hauser guitar is the head. The Hauser head consists of three lobes, a large center semicircular lobe with a quarter circle lobe on each side. The head is attached to the neck with a “V” joint. This is a very special type of “V” joint. According to Hermann Hauser III the “V” joint that the Hauser family has been using originated in 1875. It comes from the old tradition of the 13th century Fussen lute makers. Most modern luthiers who use the “V” joint today execute it in a style completely different than the Hauser tradition, yet they call it a Hauser “V” joint which is misleading. The Hauser or Fussen “V” joint is made of two pieces. The male end that is part of the neck shaft and the female end located in the head. The sidewalls of these parts are tapered so they lock into place. The female end does not go all the way through the head but stops 2-3mm short. A side view of the Hauser guitar will show that the head sticks up a few millimeters above the line of the neck shaft. What is incredible about this method of joining the head is not so much in its construction but in the fact that the Hauser’s installed the head as one of the last steps in the construction of their instruments.
There is also something curious about the male tip of the “V” neck joint. Approximately ten millimeters from the point of the male segment of the“V” there is a very well executed splice of wood that is almost invisible. This was used to increase the thickness of the neck blank so there was enough wood for the male “V” joint. This is not a consistent feature but is used in Hauser instruments from the 1950s to today. The dimensions of the “V” joint are not consistent in any Hauser guitar. Various widths and lengths have been used. The head angle is commonly set at about nine degrees. This can be found in the work of all three generations of Hauser’s.
Bridge Locating Pins
Another of the unique construction details of the bridge is the use of two locating pins found between the saddle and the tie block. They vary from two to three millimeters in diameter. Sometimes they are located under the first and sixth strings and at other times they are between the two pairs of outer strings. These locating pins extend into the top of the instrument locking the bridge in place, which would assist in locating the bridge after varnishing. The outline of the bridge would be scribed with a sharp knife and the varnish scraped away to prepare the top for gluing the bridge.
Two of the most common woods found in the back and sides of the Hauser guitar are Brazilian and East Indian Rosewood. At times Hauser Sr. would use both woods. For example, in 1936 he built a guitar with East Indian Rosewood sides and a Brazilian back. The use of maple is also found for backs and sides, but is not very common. Hauser III has frequently used a four piece back consisting of two outer pieces of Brazilian Rosewood and two maple pieces in the center along with Brazilian Rosewood sides. Bubinga has sometimes been used in backs and sides, but is the least common tone wood used in the Hauser guitar.
Hauser III prefers spruce from the Bavarian Mountains for his soundboards. Both Hauser II and III have used cedar on occasion. The majority of soundboards used in Hauser guitars are made of spruce. On occasion the tops are mismatched. One possibility for this could have been the destruction of the workshop during World War II and the surviving inventory of soundboards may have been mixed up. Or, the tops may have runout, which is diagonal grain in relation to the plane of the soundboard. Runout causes a refractive shift in the aesthetic of the top in which one half of the top looks light and the other half looks dark in color. To avoid this the Hausers may have decided not to book-match some of their soundboards but join them so that they have matching runout.
One aspect that separates the Hauser guitar from the Spanish school is the use of thicker soundboards. The Hauser soundboard thickness has an average range of 2.5-3.0 millimeters compared to the soundboards of Torres and Manuel Ramirez, which fell into the 2-millimeter or thinner range. This definitive characteristic is one of the most overlooked aspects of the Hauser design and all too often is neglected in replicas of this model of guitar.
The Hauser’s were one of the first to use nitrocellulose lacquer on a classical guitar. They first started using nitrocellulose lacquer in the 1950s, 10 years prior to the use of catalyzed finishes by the workshop of Jose Ramirez in Madrid. Hauser II refinished Segovia’s 1937 Hauser Sr. guitar in the early 1960s with nitrocellulose lacquer. Soon after this, Segovia said the first string died and stopped playing the instrument. Segovia took the instrument to Jose Ramirez III to see if he could bring it back to life. He recalls Segovia saying, “My Hauser guitar has fallen ill. It has a strange vibration and furthermore there are two notes on the first string that do not have the same intensity as the others. I would like you to repair it for me.”
The current standard used by Hauser III is to French polish the top and use nitrocellulose lacquer on the back, sides, neck and head. Since the 1960s nitrocellulose lacquer has changed and isn’t quite as hard and brittle. Hauser III has found that there is no advantage to the use of shellac compared to lacquer for sound.
Andres Segovia and Julian Bream, two influential classical guitarists of the 20th century, both performed on Hauser guitars. The best description of a Hauser guitar’s musical attributes can be found in the book Julian Bream—A Life on the Road. Here is how Bream described the Hauser guitar:“ The German instrument has what I can only describe as the very essence of classicism in guitar sound; the integration of the different registers of the instrument, whether in the extreme high positions or in the low, achieves a balance that is remarkable. The bass is deep but finely focused; it is sustained but has great clarity. The treble strings have a bell-like quality and a sweetness of tone that is never cloying. The third string which, on most instruments, can sound tubby and lacking a true center, on a great Hauser had a profound ring about it, and when played softly is quite magical. And because of this concentrated focus and clarity of sound, and its consequent fine separation of detail in both contrapuntal and chordal music, this type of guitar is ideally suited for use as a concert instrument.” After reading Bream’s description I have to wonder what it must have been like to play Segovia’s 1937 Hauser, “the greatest guitar of our epoch.” Bream admits that he has owned two good Hauser’s but not a great one.
The Spanish guitars of the Hauser tradition have influenced luthiers around the globe. Many luthiers offer “Hauser” replicas or models, including myself. My research into the Hauser tradition has opened my eyes as to what makes a Hauser guitar. In this paper I have examined the history and described details of aesthetic and construction. These details are important in capturing the spirit of this model of guitar. Segovia’s role was also a vital one in the worldwide evolution of the instrument. The meeting of Segovia and Hauser gave a non-Spanish builder a credible endorsement that Spaniards are not the only ones that can build the guitar. Since the meeting of these two greats the world of the classical guitar has never been the same. Guitar building is booming around the globe. There have never been more guitar makers than there are today and no guitar has been copied as much as that of the Hauser tradition, the Spanish guitars “Stradivarius”.
Articles & Books
Brune, Richard. “Segovia’s 1937 Hauser Revisited” American Lutherie 31 (1992): 8-13.
Brune, Richard. “An Interview with H.E. Huttig” American Lutherie 32 (1992): 16-22.
Brune, Richard. “Guitars with Guts-Top Ten Collectable Gut Strung Guitars.” Vintage Guitar Magazine April 1996: 142.
Brune, Richard. “Guitars with Guts-Hermann Hauser I.” Vintage Guitar Magazine Feb. 1998: 58-60.
Brune, Richard. “Guitars with Guts-Varnishes.” Vintage Guitar Magazine April 2001: 66-67.
Brune, Richard. “Guitars with Guts-Segovia’s 1937 Hauser.” Vintage Guitar Magazine Oct. 2003: 66-70.
Cleveland, Russel. The Classical Guitar: A Complete History. London: Outline, 1997.
Clinton, George. “Bream and the Luthier.” Guitar International. July 1985: 31-36.
Elliot, Jeffrey. “An Overview of the Hauser Tradition” American Lutherie 8 (1986): 18-27
Grondona, Stefano and Luca Waldner. La Chitarra di Liuteria. Sondrio: LDL, 2002
Huttig, Hart. “Remembering Hermann Hauser II.” Guild of American Luthiers Quarterly 11.3 1983
Jahnel, Franz. Manual of Guitar Technology-The History and Technology of Plucked String Instruments Westbrook: Strummer, 2000.
Kelly, Armin. “Meet the Maker: Hermann Hauser III” American Lutherie 51 (1997): 20-23, 37
Palmer, Tony. Julian Bream- A Life on the Road New York: Watts, 1983.
Ramirez, Jose III. Things About the Guitar Madrid: Soneto, 1993.
Riggs, David. “Meet the Maker: Klaus and Peppe Reischel” American Lutherie 42 (1995): 42- 43, 50
Romanillos, Jose. Antonio de Torres: Guitar Maker-His Life and Work. Second Ed. West Port: TBS, 1997.
Segovia, Andres. “In Memoriam-Hermann Hauser.” Guitar Review 16 (1954): 1
Summerfield, Maurice J. The Classical Guitar-It’s Evolution, Players and Personalities since 1800 2nd ed. Newcastle: Ashley, 1991.
Urlik, Sheldon. A Collection of Fine Spanish Guitars. Commerce: SKPC, 1997. Westbrook, James. Guitars Through the Ages U.K., 2002
Brune, Richard. “Re: Hauser Question and Observation.” E-mail to David Schramm. 14 Sept. 2002.
Brune, Richard. “Re: Hauser Question and Observation.” E-mail to David Schramm. 25 Sept. 2003.
Brune, Richard. “Re: Hauser Observations.” E-mail to David Schramm. 04 Oct. 2003.
Brune, Richard. “Re: Lansdorfer Tuning machines history.” E-mail to David Schramm. 25 Nov. 2003.
Brune, Richard. “Re: Hauser II Gold Medal Award?” E-mail to David Schramm. 15 Dec. 2003.
Hauser, Hermann. “Re: Guitar Question.” E-mail to David Schramm. 7 Oct. 2002
Alessi, Nicolo. “Alessi Tuning Machines” Alessi tuning machines website 24 Nov.2003 www.websnap.it/alessituningmachines/English.htm
The Documentary of Hauser Restoration Ed. Andrea Tacchi. Vers.1.07. Crane Homepage 24 Nov. 2003 www.crane.gr.jp/CRANE_Back_No/HauserRestoreAndreaTacchi/E.html
The History of the Classical Guitar Ed.Jojo McBean. Nov. 23, 2003 www.geocities.com/jojo_mcbean/sor.html
Morris, Allan. “Heinrich Albert and the First Guitar Quartet.” Sept. 25, 2003 Editions Orphée, Inc. Nov. 23, 2003 www.orphee.com/morris/heinrich.htm#Note%2011
Purcell, Ronald C. “Vahdah Olcott Bickford.” Ed. Ronald C. Purcell. CSUN. 24 Nov. 2003 www.csun.edu/~igra/bios/text/bickford.html
Rodgers, David. “Rodgers Tuning Machines Home Page” Rodgers tuning machine website. 25 Nov. 2003 www.homepage.ntlworld.com/r.rodgers/RTM/Index.htm
Stewmac.com 24 Nov. 2003 www.stewmac.com/shop/Tuners/Guitar,_slotted_peghead/Schaller_3-on-a-Plate_ Guitar_Machines.html