Photos Sounds Specifications Dan Roberts on the DKK
Genesis of an Instrument: the Santa Cruz DKK Extended
by Kevin Kastning
Extending the known range of instruments is a fascinating subject in which I've long been interested. In 2002, I began to conceive of compositions for solo guitar which involved a range below that of standard concert pitch tuning. I raised this topic with my friend Dan Roberts; he and Richard Hoover are the two principal designers at the Santa Cruz Guitar Company (SCGC). Dan is also an extraordinarily gifted luthier in his own right. As an artist endorser for SCGC, I have always felt very blessed to be able to work with Dan and to be associated with SCGC. Each of my SCGC guitars have been unusual, and no matter what my concepts or requirements, Dan and the talented SCGC luthiers have always come through with flying colors, providing instruments of unparalleled tone; but more importantly, exactly what I had wanted with the tonal properties I'd described to Dan. Additionally, Dan and I have a very unusual relationship regarding instrument design and building. Dan has always proven to know exactly what I am seeking in instrument tone and how to achieve it; a most difficult task, as describing both broad ranges and detailed minutiae of tone and instrument timbre usually translates very differently from person to person. We both speak the same language regarding luthiery, and we are both very demanding of instruments.
In 2002, Dan and SCGC were working on a very special OM guitar for me. Coincidentally, my OM has a slightly extended upper register, due to an experimental fingerboard extension. During a phone call in the fall 2002 of to discuss the progress of the OM, I raised the topic of a guitar with an extended lower range. Dan mentioned their baritone guitar to me as a possibility. The SCGC baritone has a longer scale length (27") than guitars with standard tuning, and is tuned a major third lower than standard tuning (C below E). I had never played a baritone guitar, so Dan graciously sent one out to me, in order that I might begin acclimating myself with one. Upon its arrival, I began experimenting with altered tunings. While the compositions I had in mind would involve an even lower register than that of the baritone, Dan wisely suggested that I spend some time with the C-tuned baritone. After about a month with the SCGC baritone, I realized that what I was hearing and the compositions I had in mind were in fact lower in register than the C tuning of the baritone. I began experimenting with various string gauges for different tunings, as lower tunings require heavier gauged strings. Eventually, I settled on an A tuning, which is a perfect fifth below standard tuning (A below E). I had tried a G tuning, but the SCGC baritone wouldn't handle it; in fact, the A tuning was pushing beyond what it was designed to do. The lowest part of the A tuning's register was almost unusable, as was the upper register. But I fell in love with the sound and compositional possibilities, and ended up using this baritone on nine of the eighteen compositions on the KastningSiegfried album Bichromial. Throughout the process of experimenting with tunings in various registers and the string gauges required by them, I maintained an ongoing dialogue regarding design possibilities with Dan. After spending some time with the baritone, I knew this was very close to the sound for which I'd been searching. I began to conceive of a baritone without the current tuning and register limitations. Concurrent with this process, I was writing new compositions for baritone guitar.
During a 2003 visit to the Santa Cruz shop in Santa Cruz, California, Richard Hoover (SCGC's founder) asked me to spend some time with a one-of-a-kind 7-string baritone which SCGC had built as an experiment. Dan was also very interested in my exposure to, and opinion of, the 7-string baritone. The register-lowering extension provided by the 7th string further added to my conviction that an instrument with a range lower than that of the C-tuned baritone was what I sought. I knew I wanted my baritone to be designed for G tuning (G, C, F, A#, D, G) This is a Major 6th below standard tuning (G below E). This register is also twice as low as that of the SCGC baritone. This kind of vast difference in register would require many design changes and luthiery challenges. SCGC had never designed or built a baritone with an extended range, so this would prove to be an exploration of uncharted territories for them. In the fall of 2002, neither Dan nor I could have foreseen the unusual challenges which lay ahead of us.
The baritone which Dan sent to me was based on a 12-fret dreadnaught design; with Honduran mahogany back and sides, and a bearclaw German spruce top. While the combination of mahogany and German spruce provided a crisp tone with much presence and sparkle, I felt the tone was lacking in the lower registers. In the SCGC baritone's defense, this came as no surprise, since I had the baritone tuned in ways for which it was never designed, using strings for which it had never been voiced. Still, I could hear the potential, and I felt certain that Dan could design an extended-range baritone which would provide the resonance and depth that a G tuning demanded. One of the first design changes we discussed, and which required many lengthy ongoing discussions, was the question of tonewood selection. Some of the back and side possibilities we discussed were Brazilian rosewood, East Indian rosewood, and South American cocobolo rosewood. Tonewoods for the top which we considered were Sitka spruce, German spruce, Adirondack red spruce, and Carpathian red spruce. As a back/side choice, I rejected mahogany, as I felt that it would not provide the depth and extended bass response which would be required. As we were beginning to consider East Indian rosewood, Dan had a prototype baritone which had the same specs as the one I'd been using sent to me which had East Indian rosewood back/sides, and a German spruce top. For my lowered tunings, this was a vast improvement over the mahogany version. The tone in the low A register was reminiscent of the bass register on a concert grand piano; very strong and resonant. Even the upper register was present, and it sounded full and rich. Knowing that the upper register would sound so beautiful, a cutaway would be mandatory. All my SCGC guitars have cutaways, of which I make extensive use, but due to the lack of the upper register on the mahogany baritone, I had previously thought that a cutaway would be of little use. After hearing what a difference was made by the East Indian rosewood, I also began to think about using cocobolo rosewood. My Santa Cruz D, which is my main instrument, has cocobolo back and sides, and for the tone I prefer, cocobolo rosewood has been perfect. To my way of hearing, it has all the projection, depth, and smoky resonance of Brazilian rosewood, but with far more complexity throughout all the registers. I also hear cocobolo rosewood as having more balance, in that the upper registers are very present and alive, with a mahogany-like sparkle and more detail in the upper partials; yet with no loss in the upper-register fundamentals. One drawback is that master-grade cocobolo can be difficult to locate. In fact, when SCGC built my D cutaway back in 2000, it took eight months to locate the ideal cocobolo set; Dan rejected many otherwise fine AAA-graded sets. He recommended that we wait for the ideal set which he felt would deliver the tonal properties I sought, and I agreed. It was worth the wait, by the way. Dan set about the arduous search of trying to find a set of East Indian rosewood which would be perfect for the extended baritone. This is not a short process, and can take months. I was prepared to wait patiently, as I wanted to ensure we had the sets which would deliver the most optimum tonal properties. Rather late one night in the fall of 2004, I received a call from an excited Dan. He had been meticulously examining the tonewood stash at the SCGC shop, and had discovered a back/sides set of perfectly quartered, even, and unusually straight-grained cocobolo which he called "the absolute best set of cocobolo I've ever seen." This particular set had a tap tone with a lower than normal fundamental. Dan stated that he thought this would be the ideal set for the baritone, and because of my preference for cocobolo rosewood and the fact that I had been considering it all along, I readily agreed. During the search for the back/sides set, Dan had also been seeking the top set, for which we had settled on Carpathian red spruce. Dan's experience with Carpathian led him to believe that it would be the right choice for the extended baritone's top moreso than the other tonewoods we'd considered. I've always preferred the sound of wider-grained spruce over fine-grained, and so Dan had been tone-tapping untold numbers of wide-grained top sets, looking for an extraordinarily resonant top set. It wasn't long after the cocobolo phone call that I received another call from Dan; again I could hear the excitement in his voice. He had located a very dry and stiff; yet an unusually wide-grained Carpathian set which also had a very high stiffness-to-weight ratio. Dan described the tap tone as being "like a gong;" a very, very low fundamental which just kept going when tapped. Dan felt that the top set and the back and sides sets were not only perfect for an extended-range baritone, but that the combination of the Carpathian red spruce with its low fundamental, and the denseness of this particular cocobolo set would work together in an ideal complementary way. We had our tonewood sets, which was very exciting.
String Gauges and Scale Length
Ever since the first baritone arrived, Dan and I had been having many conversations about string gauges and scale length. I had been through many different sets of strings, all custom gauged which I'd put together from single strings, as no one makes a set of baritone strings which would work in this scenario. I was having some success in matching gauge to pitch for the lower strings, but having much difficulty in getting the right gauges for the first and second strings. I eventually abandoned the idea of an unwound (plain) 2nd string, and found that a wound .020 worked pretty well. However, using the traditional unwound 1st string was still causing some difficulties. I was using an .018, but that still was too light. Since the new baritone was going to be pitched so much lower than a standard baritone, the string gauges had to be heavier, and the scale length had to be longer. Dan, knowing my penchant for heavier rather than lighter gauged strings in any situation, suggested we go with an all-wound set. Usually, the first and second strings are unwound, and while I had never heard of an all-wound set, I knew immediately that I wanted to try it for this instrument, and felt, as did Dan, that it would be exactly right for the lower pitch and longer scale. I also knew that an all-wound set would solve the problems of the 1st string being too light physically, and not having enough tonal heft to sound like a part of the instrument. Dan set about doing various designs for the new bracing the top would require. Not only would the longer scale length and the lower pitch need to be taken into consideration; now the all-wound string set had to be taken into account as well for the bracing design and voicing of the top. Eventually, we settled on 28.5 inches as the scale length, and initially planned on an all-wound set of strings gauged as .020, .028, .038, .048, .060, .076, in phosphor bronze. The longer scale raised concerns regarding the location of the bridge; Dan was sure that it should not be placed any lower on the top than the current bridge location on the SCGC baritone. And, for an instrument with a very extended scale length, which would involve the use of very heavy-gauged strings, a different bracing for the top would have to be designed. This is just one more area in which Dan is gifted. The new bracing would be based on Dan's concept of "double-tapered" bracing, which involves the cross-section of the braces to be carved in an almost knife-edge shape. As the tone bars approach the sides, they taper to a point, instead of being squared off. The tone bars and finger bracing were also redesigned to work with the double-tapered bracing. After doing some designs for the new bracing, Dan called and said that using the 12-fret D design (the one on which the current baritone was based) was definitely going to place the bridge too low on the top. As a solution, he suggested we try a 13-fret design, which as far as the D-type goes, had never been done. The physical drawback is that this would shift the neck farther to the left when the instrument was being played. However, I was far more concerned about the tone, and knew that adapting to the minor shift of the neck's location would be a small task. I agreed, and yet another design first took its place on the extended baritone. In the past, Dan and I have had many discussions about intonation compensation and break angles; both over the bridge saddle and behind the nut. I carve my own saddles, and details like break angle and intonation compensation are always major concerns for me. One day while discussing the bridge saddle thickness measurement for the baritone, Dan told me about an experiment he'd been trying, which involved tilting the bridge saddle backwards (toward the bridge pins) at a 10-degree angle. This provided for an increased break angle, and allowed more string-to-saddle contact; thus allowing for more control over intonation compensation. He asked if I wanted to try this design on the baritone, and I said I did. Another first. There were many other design deviations from the standard baritone; some of the changes were nut width, an all maple rosette and purfling, bridge saddle width, neck profile, SCGC 18:1 ratio tuners instead of Waverly, lack of an endpin, no position markers or inlay on the fingerboard, lack of backstrip inlay, cocobolo neck heel cap, overlay, and end graft, no pickguard, 1/8"-width bridge saddle; among others. Even the tuners would require modification: the string holes in the tuner barrels on some of the strings proved to be too small, and had to be drilled out. Another design element I wanted was a dark violin-like stain for the finish of the top. SCGC had never done anything like this before, and I felt as if I had to talk Dan into it! Eventually he agreed, and when it was all done, he admitted that he liked the look of it much more than he had anticipated. SCGC dubbed this stain color "Cremona brown." Since we were trying to achieve a violin-like stain, naming the stain color "Cremona brown" was a reference to the historical master luthiers of instruments of the violin family such as Stradivari, Guarneri, Amati, et. al., whom had been based in Cremona, Italy.
The DKK Baritone
So, from our first discussions in fall 2002, finally in October 2004, Dan and I had settled on full design specifications for the new experimental baritone. In fact, this baritone was so different and virtually unrelated to the existing SCGC baritone, that it was assigned a new model designation: the DKK (D for dreadnaught body type; KK for Kevin Kastning). Work at the SCGC shop began in November 2004. I was very excited that our two years of discussions and planning were finally being realized. There was a small part of me which was wondering if the instrument would really live up to what I'd hoped it would be; after all, there had never been anything like this one, so it was a bit of an exploration into the unknown. After the specification that the baritone be pitched in a G tuning, my next largest concern was that the instrument should be equally responsive in all registers, which is a high demand for any stringed instrument. It was even more of a tall order for this one, as most of its design was aimed at being in a lower register; therefore, how would the upper registers work to achieve an overall balance? While I had full confidence in Dan's design and luthiery gifts and expertise, there was really no way to know how all the disparate design requirements would meld until we had the final instrument. Work on the DKK was completed in March 2005. Dan did the final setup and voicing, and shipped it off to me. During the setup process, I had asked Dan many questions: how was the tone? Was the lower register as full as we had hoped? What about the upper register? Dan was positive in his assessments, but noticeably reserved. In early April 2005, the baritone arrived at its new home. Upon opening the case, I was taken aback at the instrument's visuals. Dan can confirm that I've never been very interested in how an instrument looks; only in how it sounds. However, I must say that visually, this was perhaps the most striking instrument I'd ever seen. All of my fears about whether or not we could achieve a fully balanced instrument in such a low tuning with so many unknown elements were laid to rest on the first day of playing it. Not only had Dan and the luthiers at SCGC achieved all I'd hoped for, they once again went above and beyond. The lower registers on this baritone are very full, rich, and just huge. The upper register has a wonderful singing quality which sounds like the upper registers of a cello. I called Dan, and told him how happy I was with the instrument. He told me that he had in fact been very thrilled with the sound and how it had turned out, but didn't want to say anything until I'd had a chance to play and hear it. After 2 1/2 years of design work on Dan's part, and all the discussions and string gauge and tuning experimentation had all paid off far better than I could have hoped.
I have already been in the recording studio with the new DKK baritone on compositions which will appear on the forthcoming Greydisc Records release of the new KastningSiegfried album, "Scalar Fields," scheduled for release on November 15, 2005. Getting used to the long scale length did take some intensive practicing and acclimation at first. After a few weeks, it came to feel very natural; although not without some fingering challenges along the way. Ironically, though I had envisioned this baritone as a much lower-range instrument (and it certainly is), I am constantly amazed and in awe of the upper registers. I find the upper register of the DKK to be so euphonic and so rich, that I have used this guitar (mostly in the upper registers only) in place of my SCGC D on some compositions which were written for concert-pitch standard tuning. There is at least one track on "Scalar Fields" wherein the entire piece was performed using only the upper registers of the DKK.
To Dan, Richard, and everyone at Santa Cruz, for making this cello of the guitar family, my sincerest gratitude.
Postscript: After further string gauge experimentation on the DKK, and based on all the string gauge experiments from the first two SCGC baritones, it became apparent that a slightly heavier string would be a better choice for the low G. I'm an artist endorser for John Pearse strings, and as such, I approached them about producing an .080 phosphor bronze double-wound string. I am very happy to report that John Pearse not only agreed to make this, but will be adding it to their catalog. I received my first batch of the .080s in September 2005, and I am very pleased, both with the strings themselves, and how beautifully they work as the low G string on the DKK.
Tentatively scheduled: The DKK baritone will be featured at the Santa Cruz booth at the 2008 NAMM Show in Anaheim, California. I will also be on hand at the Santa Cruz booth as their guest at the 2008 NAMM show.
Update 1: Since the recording sessions for Scalar Fields have concluded, I have been experimenting with the tuning and string gauges of the DKK. Currently, I have it tuned to F# (F#, B, E, A, C#, F#). String gauges for this tuning are: .022, .030, .040, .050, .064, .080. All phosphor-bronze wound. My string gauges and tunings for all instruments can now be found here.
Update 2: I am pleased to announce that John Pearse Strings have added my .080 double-wound phosphor bronze string to their catalog, and it is now available.
From the KastningSiegfried album Scalar Fields: Macrolibrium 7 (intro)
Additional DKK audio examples may be found here.
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