Volume 7, Issue 1, January, 2008
The "Expanded" Harp Guitar -
Adding Possibilities with Super-Trebles
by John Doan
What it is and who and where it came from
I play a twenty-string harp guitar that has three string bank groupings, with six guitar strings in the middle, with six sub-basses to the left, and eight super-trebles to the right (as viewed straight on from the front). This extends the range of the guitar to five full octaves, greatly expands the resonance, and adds general facility in playing the highest pitches. The additional strings eliminate one major challenge of the six-string guitar, which is that a player has to do two things to get one note by having to pluck with one hand while the other hand fingers the note plucked, unlike the piano or harp which can create tremendous variety of effect with ten fingers each doing only one activity to play one note.
I didn't invent this form of harp guitar. I have to credit Chris Knutsen (first patentee of the harp guitar in America) for coming up with this ingenious idea over a century ago. Although various examples of super-treble strings on harp guitar-like instruments pre-date Knutsen's in Europe (poliphont, torban, bandurria, etc.) he worked at making them available in America as early as the 1890's, and it is his basic design that my Sullivan/Elliott instrument is based upon. He thought so much of the "expanded harp guitar" that he chose to pose with this instrument with his family in the earliest known photo of him, as well as making one for his wife which she posed with in a later family photo. It is worth noting that harp guitars with sub-basses only were once more numerous; however, after more than twenty years of composing and performing on the expanded version I have seen increased interest on the part of players and builders for this form of harp guitar in recent years.
By living in the Northwest near where Knutsen constructed his harp guitars I managed to run across several of this version of harp guitar.
I still own a circa 1898 18-string model that I used in my earliest harp guitar recordings (at left).
Why I am writing this article
The playing and making of harp guitars today is causing a re-examination of many basic design features that go into making a fine guitar-like instrument with an expanded range. The six-string guitar world is alive and vital today but with the addition of sub-basses and super-trebles entirely new dimensions and fundamental questions arise that are not being commonly discussed among six-string guitar builders. I have concluded that after reviewing and playing many prototype designs today that simply having skills as a six-string guitar builder is not going to result in a great harp guitar. Harp guitar construction in many ways is a very different activity than building a six-string instrument.
The following is no doubt an incomplete list of some new questions that adding additional strings pose to the construction of a harp guitar:
In this article I will try to address the above questions and share with you some of my musings about why I think the harp guitar with super-trebles and sub-basses is a great version of this instrument. I also hope to clarify for both players and makers alike some of the guidelines I have come to believe important to the design of this version of the instrument, and to encourage dialogue toward more thoughtful future designs.
Most harp guitar players are primarily six-string guitarists and are exploring the harp guitar as a standard guitar with additional sub-bass strings. It appears that the harp guitar has still not come into its own and is still seeking a standard. This article is for those intrigued by the possibilities of expanding the guitar's range in both directions!
In future writings I plan to explore both how to play the instrument and address crafting music to be played on it, as this version of harp guitar requires the player to think differently about the expanded possibilities the additional super-trebles bring.
My first encounters with the harp guitar
My introduction to the harp guitar was the acquisition of a Gibson c.1906 harp guitar with six sub-basses in 1979. Kent Raymond of Portland, Oregon beautifully restored it at that time. I had been playing a Renaissance lute (8 courses) and a Baroque theorbo (14 courses) for several years previously, and found that a guitar with extra basses fit right into what was making sense to me with the historical music I was playing.
The folk scene was big in Oregon when I moved up from Los Angeles in 1974 and it was great fun then to explore the American Fingerstyle Guitar that John Fahey championed. In fact he lived in my adopted hometown of Salem for the last twenty years of his life and was a great friend and inspiration. This fingerstyle approach to the guitar is at the root of much of the music that is now played on the harp guitar today (Stephen Bennett, Andy McKee, etc).
Also at that time I began collecting various fretless zithers that had been discarded over the years and began to enjoy their wonderful bright and sustaining treble tone. The Tremblelin was one of my favorite zithers and I actually recorded my first album with it. It has a set of 4 chords of four strings each placed to the left of fifteen pairs of strings used for melody. I pluck them with my fingers or use the nifty piano keyboard that is connected to a series of spring wires with lead weights attached to each end. When played with the keys it imitates the tremolo of the mandolin that was so popular a century ago.
In the early 1980's when playing at the Northwest Folklife Festival in Seattle on my Gibson harp guitar and Tremblelin zither, I went to the festival's annual instrument auction and could hardly believe my eyes when I saw an old Knutsen that not only had sub-basses but super-treble zither pins as well. It was everything I was doing all put together into one instrument! After buying it I had to figure out what strings I would use on it and how I would eventually tune it.
Tuning the bass strings
Knutsen had printed on the inside label of many of his instruments about tuning the basses diatonically from the guitar's sixth-string E downward to D, C, B, A, G. Stephen Bennett and other harp guitarists have been exploring other tunings for the sub-basses, especially with a "G" (the same note found on the third fret sixth string) as the first sub-bass. Obviously, you can try any arrangement that is possible, but all of my music is for an instrument tuned progressively down diatonically as Knutsen suggested. This to me is the simplest design of descending basses just as was used for the Baroque theorbo, and is consistent with the logic of the white keys of the piano keyboard.
On the other hand, if you are wanting to play Stephen Bennett's harp guitar pieces (or others who tune similarly) you may want to tune the sub-basses like he does. For those playing in DADGAD you may want to look at tuning your first sub-bass also to "G" to give you the bass note for the G chord in the key of D, or explore tuning the first sub-bass to "C" and then descend diatonically as your sixth string is already a "D".
Steel or nylon sub-basses
On my first Knutsen harp guitar I tried all steel strings at first, then nylon classical guitar bass strings for the sub-basses, but was never really convinced that either sounded consistent with the guitar portion of the instrument.
I have strung my Gibson harp guitar sub-bass strings with steel strings from the very beginning and they sound great on that guitar. My Gibson is an early model that has its strings attached to the bridge which is glued to the face of the instrument, as opposed to the later models that had a flying bridge which the strings crossed over and attached to a tailpiece that was connected to the end block. I have found that these early models sound best to modern players. I also have heard several old Knutsens that sound pretty good with steel sub-basses. Gregg Miner has a Knutsen Symphony harp guitar with steel sub-bass strings that has amazed many famous guitarists who have had a chance to play it. He claims it has the best-sounding sub-basses he has ever heard.
Over time, I have found that there are several advantages to using nylon sub-basses. My Elliott/Sullivan harp guitar is fairly light in its construction, and nylon sub-basses require less tension to bring the strings to pitch than a steel string. With less tension on the instrument there is less chance for the face of the instrument to distort or crack.
The nylon strings emphasize bass frequencies, which is desirable in the bass as opposed to a bright attack that is associated with a steel string. Another advantage is that once plucked the tone decays quickly as opposed to the sustain of a steel string which muddies up the music and requires a lot more damping techniques to control.
Played acoustically, steel strings in the bass are definitely forceful, but once amplified, either through a microphone or a pick up system, the nylon basses speak with just as much authority and tend to sound warm and full without the tendency of a steel string to thud like a bass key on an old piano. Many playing techniques however, can affect the tone as well on whichever type of string you choose for sub-basses such as using more flesh than nail to pluck the string or the distance from the bridge where the string is plucked.
Test for choosing sub-bass strings:
I have found that the challenge in choosing sub-bass strings is to first find strings that sound great on the guitar neck. I look for each note sounding full and true. If the note is not clear and true to the pitch you want to tune it to, you may need to replace the string with one of a larger diameter. Too slack a string will not speak very loudly and will have problems playing in tune.
I have been using the Elixir 80/20 Bronze Light-Medium strings (.012 - .056) with their original "Polyweb" coating on the central guitar portion of my Sullivan/Elliott harp guitar. Your choice of strings may vary according to your instrument's construction and your individual playing style. A heavily constructed top may require heavier gauged strings to make it speak well. A thinner and more lightly braced top may require lighter gauged strings.
It is worth noting that many antique harp guitars, especially European contraguitars, were made for gut strings and sub-basses of over-spun silk (not unlike modern classical guitar strings). Take care not to use steel strings on these guitars, or to use too heavy a gauge string on instruments that are lightly built as you may cause damage to the instrument.
This next step may require you to purchase bass strings of a variety of gauges to discover what works best on your harp guitar. Once you have selected your strings for the guitar continue to work downward to get the first sub-bass to match the timbre of the sixth string on the guitar. My aesthetic choice is to keep the instrument consistent sounding across all twenty strings, much like the sound of a piano (throughout this discussion you will find me referring to the piano as a model). Repeat this process from string to string until the sub-basses and the guitar sound like they are speaking from the same instrument.
I have heard many harp guitars that do not sound consistent across their range, which in most quality instruments would be considered a flaw or error in design or construction. I believe it a compelling aesthetic to aim for a consistent tone across the instrument's range, and that is what I would like to see adopted in the construction of all forms of harp guitar.
I personally enjoy the warm and less metallic tone of the Elixer strings which has led me in part to explore using nylon-core sub-basses that more evenly match the tone of the Elixer sixth string portion of the instrument. Another good reason for the nylon-core sub-bass strings is that they exert less tension than steel strings, and with twenty or more strings attached to the bridge this can help prevent the face from distorting or cracking, especially if it is lightly constructed.
A note to makers experimenting with string lengths for sub-basses
If your design has the sub-bass strings of the same length or shorter than the guitar strings on the main neck you will probably not be able to achieve an evenness of timbre with the guitar's six strings simply by applying larger string gauges descending. Added length with heavier gauges is historically the way to go as you get deeper pitches from the strings while maintaining a consistent timbre across their range.
String length and tuning the super-trebles
At first I was unsure how to tune the super-trebles on my century-old Knutsen. I thought maybe I would like to get the "f" that I would ordinarily find on the first guitar string at the first fret. When I used the same gauge string as my first guitar string for the first super-treble, it did not speak well until I tuned it to an octave above the first string, which was about the same length as fingering that note on the 12th fret of the first string.
Not realizing that I had discovered my eventual tuning and the principal behind it, I continued to change strings a guitar fourth string as my first super-treble produced the good strong tone of the "f" of the first fret, first string that I originally set out to find. What became apparent was that this note found on the guitar's fourth string at the 15th fret was approximately the same string length as the "f" note I was now getting on my first super-treble.
Eureka! I had found a basic principle to determining the tuning of the super-trebles that would suit my goal of matching the timbre from the guitar to the super-treble bank, similar to what a piano achieves in graduated pitches of similar timbre. So if you want the guitar portion of the instrument to work together with the super-treble register in the most seamless manner you have to consider the string length and diameter. Given that the 12th fret on the first string was about the same length of string as the first super-treble string I was able to achieve a smooth transition to the super-trebles from the guitar and vice-versa, by starting with that string being tuned an octave above the open first string and with the same gauge of string. Once that was determined I could use the harmonic arc of the tuners on the face of the instrument to aid in tuning each successive string up diatonically from there (as in the piano).
Given that standard tuning is predominately an e minor chord I chose to tune the super-treble bank to an e minor scale as my home tuning. As I play in other keys I make adjustments not unlike a traditional harpist does. I did find that I needed to lessen the string gauges as I got to the highest pitches in order for them to ring and sustain like the lower super-trebles.
An additional simple test to see if you have even timbre between the super-trebles and the guitar would be to play your 12th fret of the first guitar string and then play the first super-treble string. If they sound very similar you probably have a good balance between the guitar and the super-trebles. Try also playing the tenth fret of the first string of the guitar, followed with the twelfth fret of the same string, then with the first super-treble. It should sound very similar, and in the best of all circumstances, seamlessly melodic.
Several makers are now adding sharping levers to the super-treble bank which makes the changing of keys much simpler. Mike Doolin, Orville and Bob Milburn, and Stephen Sedgwick are among several luthiers who have developed successful sharping levers.
Holding the instrument
Find a way to hold the instrument that will give you the most confidence and accuracy without straining your back.
I have tried playing the guitar while standing but for all that I do on the instrument I found my accuracy was increased while holding the instrument seated. Crossing one’s legs or resting one foot on top of the other has really been a sure way to put a chiropractic visit into my future! A short informal time of playing seems to forgive almost any posture, but be concerned about prolonging it for the length of a concert or for the hours of practicing we all have to do. I have used a classical guitar footstool and have tried various guitar supports with varying degrees of success. Foot stools lift one's leg up and actually tend to stress the opposite side of your back if you stay at it for hours on end. The guitar supports with suction cups failed as my instrument was too heavy and actually broke the plastic connection to the suction cups. I have been using the Gitano guitar support for years now and enjoy how it folds down to allow both of my feet to be flat on the floor while playing, then folds up and out of the way when not in use. I had it bolted on below the super-treble bout to support the weight of the instrument. (If you do this, be sure to reinforce the sides where the bolts pass through, to avoid splitting them.)
"The First Modern Harp Guitar"
In 1985 I commissioned what Jeffrey Elliott claims is
"The First Modern Harp Guitar" that would approximate the piano in its
evenness of timbre, separation, tonal pallette, touch
Some new ideas in the Sullivan/Elliott design
All strings are evenly spaced similar in concept to the piano keyboard.
This allows for a consistent logic in fingering the instrument. It is worth noting that several of today's instruments do not space the strings evenly. It is my opinion that these designs need to be reevaluated to use the logic of the piano, or better yet just continue the logic of the guitar with its even spacing across six strings. There simply isn't time to adjust for uneven string spacing if you are playing at a high level.
All strings are on a parallel plane.
Regarding not having the super-trebles on the same plane (usually lower than the guitar strings), I was told that players either commissioned this or luthiers designed this into the harp guitar so as to avoid inadvertently playing an open super-treble string while strumming. I believe that with more experience playing super-trebles, the player will come to realize that this is really an issue of technique and does not require a redesign of the instrument. My experience is that the player's technique will adjust to prevent hitting the super-trebles much like a guitarist naturally avoids the fifth and sixth strings when strumming a "D" chord that should only have the first four strings strummed. When I play with the New Christy Minstrels we do a lot of strumming and I have simply learned to strum only the strings I need. Basically, I avoid the super-trebles, and sub-basses for that matter, if I don't need them.
Configuring string gauges for a balanced timbre
In order to have a consistent timbre from the guitar through the super-treble banks all the super-trebles should be the same gauge as the first guitar string, and each one the approximate vibrating length of their pitch as found on the first string of the guitar.
(i.e.: the first super-treble should be pitched at an octave above the open first guitar string corresponding to the note found at the twelve fret). The highest pitched super-treble strings most likely will need lighter gauges to compensate for the lack of accuracy in keeping the strings at the same string lengths as on the guitar neck. Given that my music stems from this tuning, anyone wanting to play this music or expand upon the sonority of it should consider string lengths for the super-trebles that will give them those pitches to maintain the balance of tone with the guitar strings.
I have seen several harp guitars with the super-trebles much shorter than those I just described. Luthiers have told me that they can get the same pitch as I have on my instrument by going to heavier gauged strings. My critique of this is that they do not have the same timbre and do not sound evenly matched with the guitar portion of the instrument.
It is worth noting that various instruments have been built with super-trebles set off at a different angle than the six strings of the guitar neck. Some builders and players feel comfortable with the extra reaching to play these strings and even enjoy that they may have a different timbre than the rest of the instrument. The instruments of Fred Carlson and others are amazing to look at and listen to. These instruments may be intended to work within their own aesthetic to achieve different and even novel musical effects.
12-fret or 14-fret neck/body joint
A 12-fret neck/body joint helps insure balance and evenness of overall response.
I have found that the 14-fret neck/body joint usually happens because the maker or player commissioning the harp guitar wants to have a 14-fret neck/body joint or more instead of a 12-fret neck /body like on many of today's acoustic 6-string guitars. My choice is to use the 12-fret neck/body and get higher pitches with the super-treble strings that sound balanced with the rest of the guitar. Besides this advantage Jeffrey Elliott has pointed out to me that the entire guitar sounds more even and balanced and the tone is richer and fuller with the 12-fret neck/body joint, as it positions the bridge in the center of the lower bout. After all, the 14-fret neck/body joint, not to mention the addition of pick guards, were innovations of guitar design based on function rather than balance and tone.
Segmenting the long, single-piece bridge into nearly separate sub-bass, guitar, and super-treble string banks allows greater sustain and separation of response without sacrificing overall balance and evenness across the full range.
A major problem I felt I was having with the old harp guitars is that they seemed to have three separate registers instead of a unified sound coming from one instrument. According to Jeffrey Elliott this had much to do with the internal top design, but we also found that the bridge design had a part to play as well. This is not normally an issue for the 6-string guitar, but by adding a bass register, and on the expanded harp guitar a super-treble bank as well, we have entered into new sonic and design areas requiring new strategies to achieve a mature sounding instrument that speaks evenly with a balanced character.
Elliott has pointed out that although a single one-piece bridge as found on historical harp guitars actually helps unify the overall response of the instrument, its bulk usually severely restricts the more subtle realm of the response spectrum. Most historical harp guitars do this more than the modern Dyer copies. In this writing I am mainly addressing the bridge of a harp guitar with super-trebles. Granted, many of today's players are making great music on the old designs, but it is my opinion that segmenting the bridge design should be considered when desiring to optimize the clarity, separation, and balance of a new instrument. It becomes critical when adding super-trebles.
Years ago people described my playing of the old harp guitars as sounding like three different instruments, a guitar, a bass, and a zither. Today, instead I am proud to simply present them with a modern the harp guitar that has good balance across all registers.
String attachment to the bridge
Anchoring the strings on the bridge rather than with the traditional pin-and-hole method eliminates both the necessity for the internal hardwood bridge plate and the risk of the bridge cracking across the string holes, and allows for much more freedom in how the top is braced.
In order to brace the top like he wanted to Jeffrey Elliott used a bridge design with holes drilled through a tie block, like on a classical guitar. I simply place the string in the hole and pull it through, drawing it over the bridge saddle and up to the tuners. This design also allows me the option of tying on my classical basses like on a classical guitar (see above photo).
Bracing of the top
The bracing of the top needs to be just right; it must withstand all that string tension without impeding the tops responses.
Jeffrey Elliott came up with a hybrid X and fan bracing design with the bass side of the X arms free of the top and with the fan braces passing under them. You may want to look at his design pattern in an article by Jonathan Peterson entitled "A New Look at Harp Guitars", which was published in both the Guild of American Luthiers Quarterly Journal American Lutherie Magazine, summer 1993 issue #34, and in The Big Red Book of American Lutherie, Volume 3, pages 334-337.
© Jeffrey Elliott
The "One Armed Harp Guitar"
The bass arm of the harp guitar adds warmth of tone to the instrument and its size needs to be considered when looking into finding a balance of tone across the instrument.
In designing my harp guitar John Sullivan and Jeffrey Elliott wanted to use the "Gibson post" idea for supporting the sub-basses instead of going to the "One-Armed" sound chamber of the Knutsen and Dyer. It would have been a lot easier to construct, but after placing newspaper in the arm of one of my old Knutsens it was notable that without the paper it had a much warmer tone. Jeffrey felt the bass on the Knutsen/Dyer harp guitars was not balanced with the rest of the instrument and so designed it with less volume by slimming it down. I think he got it right, and would therefore want to encourage builders to consider this volume/balance issue when constructing an arm for the harp guitar.
Woods used for the back and sides of the harp guitar
Using a hard dense tonewood for the back and sides can add stability to the harp guitar, and helps ensure good projection.
The traditional steel string guitar tonewoods of mahogany, maple, and East Indian and Brazilian rosewoods can make wonderful sounding guitars, but John Sullivan and Jeffrey Elliott were looking for additional stability and projection to us with a travel-smart design. They found it in African blackwood rosewood for the back and sides of my instrument. I have been traveling with my Sullivan/Elliott all over the world for more than twenty years and it is still going strong! I do not need to tune it often as it remains very stable unlike my Knutsen which would go out of tune once the stage lights hit it or I took it outside, etc. My only concern is that it makes the instrument very loud and one might consider using ear plugs to protect one's hearing during prolonged sittings with the instrument. Recently, Stephen Sedgwick has been experimenting with creating a double thickness for the sides using mahogany with great results in stability and projection.
Spruce still a great choice for the soundboard
A European spruce top seems to work great for balance and long life especially in warming the super-treble bank.
I have heard various other harp guitars with redwood tops, cedar, koa, etc. Even Sitka spruce is brighter in tone than European spruce. Because I was looking to subdue the super-treble tendency to be too bright and edgy Jeffrey Elliott recommended European spruce. He feels that spruce is inherently more clear than any other top wood, and European spruce has the broadest tonal range of any top wood. I am sure with various strategies for design other woods could work well but I have found European spruce to be a winner.
Unified neck and headstock
A single piece construction of the neck and bass-arm headstock adds stability to the entire instrument and enhances resonance.
This is one of the basic principles of Jeffrey's design, which does not exist in historic examples.
John Sullivan found a single piece of mahogany for this fundamental design feature which has withstood the test of time.
© Deirdra Doan
Lots of tuners
Tuners need not only hold the strings in tune but must be user friendly for the player.
In an effort to reduce head mass and weight, the tuners on my Sullivan/Elliott were closely spaced, and new, smaller buttons were made so that I could get my fingers around them. Later, I recommended alternating banjo tuners out the back of the headstock with guitar tuners showing over the top, which also made it easier to tell strings apart for tuning. The super trebles are fifth-string banjo tuners with their internal shafts cut down to lower their profile, again with new, smaller buttons for closer spacing. Several makers are adding sharping levers which I would love to have someday. Fine tuners are also a great idea for use in the super-treble bank (look for Stephen Sedgwick's new design he is developing for fine tuners).
Overall, if truth be told, it probably doesn't matter how many strings you have on an instrument. It's all about the music.
If Jake Shimabukuro can make an audience cry by playing his four-string ukulele, then twelve or twenty-one strings on a harp guitar appears not to really be an issue after all. It is the heart that you bring to your playing that can move audiences and mountains! I am simply striving here to share part of my journey of considering thoughtful design and construction elements along with proper string so I can get on with making music intended to move people. I truly love the increased range, resonance, and facility the harp guitar lends to my music making.
Harp guitar evolution
The harp guitar is continuing to evolve as makers and players define the possibilities for the instrument.
So there you have some of the ins and outs of the "expanded" harp guitar. I keep seeing more and more harp guitars equipped with super-treble strings at each Harp Guitar Gathering. There are several early harp guitars with super-treble strings built by John Westling of Sandpiper Music. Most recently of note were the added strings Kerry Char placed on Nate Bluestein's instrument; a prototype twenty-one string harp guitar by Stephen Sedgwick; an electric harp guitar with super-trebles by Rich Mermer; and a Mozzani replica with super-trebles by Benoit Meulle-Stef. Look for an innovative design coming out of Austria that is a super-treble attachment to a standard six string guitar designed by Harald Peterstorfer and Gustave Walden. It is also noteworthy to point out Alan Perlman’s arch-guitar treble attachment (which Gregg Miner affectionately dubbed the "side car") for James Kline. Many other new designs with super-trebles are being added to the Harpguitars.net galleries all the time, and even Muriel Anderson has recently commissioned Mike Doolin to build her a new harp guitar with super-trebles.
Who knows, perhaps we may have to add one more figure to the new logo of guitar evolution that places to the far right the harp guitar with super-trebles!
The guitar world was saddened by the loss of John Sullivan April 21, 2007.
Note: Special thanks to Gregg Miner for his careful reading of this article and fine suggestions, and to Jeffrey Elliott for his continued support and invaluable editorial input to this article and to the evolving dialogue about the harp guitar.
About the Author
John has been performing and recording on the harp guitar for over twenty years, has appeared on numerous samplers for Windham Hill Records, has an award winning release "Eire - Isle of the Saints (voted best Celtic Album of the Year) on Heart's O'Space Records, has received Billboard Magazine's "Editors Choice" for "Wrapped In White", has been Emmy-Nominated for "Best Entertainment Special of the Year", and was recently featured in a PBS special Primal Twang - The Legacy of the Guitar". All of this was with the twenty-string harp guitar in his hands. When not on the road, John is Associate Professor of Music at Willamette University in Salem, Oregon.
To sample his music or view videos of John playing go towww.johndoan.com or check him out on MySpace and on YouTube. An overview about the harp guitar can be found on one of John's DVD's "In Search of the Harp Guitar - It's History, Players, and Makers" available at harpguitarmusic.com.
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