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Dan Roberts of The Santa Cruz Guitar Company on the Santa Cruz DKK-12 Extended Baritone 12-String

IT BEGINS: When Santa Cruz artist endorser Kevin Kastning approached me with the idea of a 12-string baritone, I really liked the idea of making an instrument with such a wide dynamic range and pitch range. My first response, (That NO WE WOULDN'T build you a 12-string baritone), was simply a matter of policy! One of our policies has been that we won't do 12-string slotheads, because we have to modify the tuners, otherwise the headstock would have to be way too long. The worst case scenario can be that we have to get the tuners, modify them, then send them out to have them plated. So just the tuners alone can be a huge logistical nightmare, but I had recently done one, and I had found a method to do it that worked out really well. I decided that wasn't going to be as large of a problem as I had originally thought. The other thing that scared me early on was that when we built the DKK, we built it lighter than you normally see an instrument like that. Yet it has held up incredibly well, and I totally believed that it would. The idea of adding on another set of six strings, on top of those already heavy strings just seemed daunting. So how would we engineer the ability to hold up under those stresses? I began to think about our experience working with different string gauges, and how much lower the tunings would be, as well as our success with the DKK. We already had a structure that was both responsive and yet plenty strong to hold the tension of such heavily gauged strings. So I thought there was no reason in the world we couldn't accomplish the same thing with a 12-string. A 12-string at standard concert pitch had never been a problem for us. I also felt that this particular configuration, the 12-fret body, is much better for those kinds of tensions than a lot of the other body shapes. For example, the 12-fret D, as light as it is when we build it, hardly ever needs a neck reset. I've seen some that are years old, and neither the neck nor the tops ever seems to move, yet they're one of the lightest and most responsive instruments you could ever hope for. So, I knew if any configuration would hold the extra stresses, the 12-fret D shape would. My initial hesitance to commit to the project was based on these questions of sheer mechanics and engineering.

 I've never been a big fan of 12-strings; to me they always sound too jangly at standard pitch; however that isn't to say that I haven't heard them played incredibly well which transcends this. Initially, I really liked Kevin's idea of a non-standard-pitched 12-string, putting it into a richer frequency area. Musically, I thought this would work really well. The other thing that changed my view on this is that I really enjoy working with Kevin on these unusual instruments. Often when we build something specifically for someone, it won't be based on a specific artistic reason. Someone will think an idea for an instrument is cool, or they think it will sell well, or reasons like that. But there is a real draw to having a musician approach you with a real need for a particular instrument that doesn't exist. That to me is like the ultimate challenge. My experience with all of Kevin's instruments up to this point had been very fulfilling for me. So I felt really excited about the possibility of not just reconfiguring an existing model for specific tonal reasons, but actually building something entirely new which didn't exist. When Kevin came to me, he basically left the designing in my hands, but told me what he wanted it musically to do. Probably the most fulfilling thing for me as a luthier is for someone to come to me with a specific artistic goal in mind. It was to be a great challenge, and he gave me the latitude to get there. To build something that will serve all these purposes and still be tonally what is needed, to be musically what is needed, that can be the ultimate challenge.

THE TOP:  We acquired about 16 sets of tops from a very old, standing dead for years, Sitka spruce. The exact origin is unclear, but this Sitka tree was most likely from northern Washington, or possibly Alaska. We had a relationship with the tonewood supplier; this was the same supplier from which we acquired the famous "Grey Ghost" Sitka sets. We asked the supplier to locate some very special, unusually wide, stiff grained Sitka sets. We had planned to select a single set from these to be used for a 000 for Norman Blake, as Norman had specified a Sitka set with unusually wide and stiff grain only. There had only been two top sets available from this particular flitch which seemed stiffer than the others from this tree. One went to Norman Blake; the other one went to the DKK-12. The tap tone was very strong, and had strong tonal characteristics; resonances all over the map: there was a strong bass note and there was also a very present treble response. This is unusual. The tap tone varied, based on where I tapped it. One of the things I do personally to evaluate a piece of tonewood is to tap it in a variety of places all over the top, as well as varying the spot I'm holding it, in order to evaluate its range. I hold it between my middle finger and thumb, and move the node which becomes where ever I'm holding around a bit till I find the spot that yields the most sustain in as large a number of areas as possible. From there, I can start tapping it in different spots, with different attacks in order to evaluate the top's resonance and sustain in different frequency ranges. Sometimes I will use my fingernail, or a felt piano hammer, in order to help vary the attack. Relative to where you're hitting it, and where you are holding it, the tap tone will tend to develop more bass or more treble response; you can hear everything from the degree of sustain and openness to a bit of a tendency to hear where the tonewood will deal better with basses or treble notes.

I felt that this top was very stiff, though the stiffest woods don't always yield the greatest sustain, this piece not only had a really incredible sustain; it seemed to have a really wide dynamic range as well. It had a wider than usual range of frequencies where I was noticing a really strong sustain, which led me to believe that it was going to be very good for everything from really low frequencies, all the way up through the higher frequency octaves that would be present on the 12-string. Many times you'll find a few frequencies which have stronger sustain than others, but this had a wide range of frequencies to which it was responding and sustaining. Compared to the Carpathian red spruce top we used for the DKK, this had even a wider range of frequency response.

Although for the DKK, I wasn't looking for a very broad range of frequencies, because I knew it was primarily going to be a more bass-oriented instrument. So in that one, I was looking particularly for a strong response in the bass range; whereas with the DKK-12's top, I was looking for an ability to sustain and have separation in order to also be conducive to the treble range and the octave strings.

DESIGNING: When we were choosing bracing stock, I was looking for an X brace which would give me really good bass response. We had some Sitka, and we had some Adirondack red spruce, and I had to find the bracing which would give the strongest bass response for the X brace. Something with a lower fundamental frequency when I dropped it and listened to the tone it created; I wanted that on the bass side, and then some bracing with a brighter tone for the treble side. I chose something really stiff for the bass side, and for the bridge plate, we went a little thicker, but only to the same degree we normally would for a standard 12-string. When we laid out the 13-fret design, a lot of decisions were already made due to the DKK. We knew we were going to go with the 13-fret design because that would put the bridge in the best place for this extended scale length. We used a 13 fret neck joint on the 12-fret D body, this 13 fret neck joint shift countered some of the longer 28 1/2 inch scale; this had the effect of keeping the bridge in a similar place to that of the 12 fret Brozman with a 27-inch scale. This is what we did to great success on the DKK. We knew this would accomplish musically and tonally what we wanted. Then we continued choosing the bracing based on tonal properties. When Joseph, the top carver at SCGC and I did the final voicing, we were looking to hear good sustain across a real wide frequency range, without losing responsiveness. I knew that for Kevin, this responsiveness was going to be really important. I had a history with Kevin, and I knew what worked well for him, and what he was looking for and why, in some of the other instruments we'd made for him. Based on our conversations on this one, I felt like I had a good background to know what he needed. A lot of the design ended up being based on our standard 12-string designs. We were manipulating so many factors: string tension, scale length, and so on, that we needed about the same amount of tension-holding ability that would be required on a standard-pitched 12-string. I felt we wanted to come pretty close to having the same tension as a standard 12-string. We would accomplish this by matching string gauges to the pitches they would be tuned to so that the tensions would come pretty close to the standard 12-string; only slightly more tension should be needed. Especially given the stiffness of that top, I felt we'd have no problems with those tensions. As far as the carving of the bracing, the DKK had double-tapered tone bars, and a scalloped X brace. On this one, we did double-tapering throughout, except that we scalloped the side struts. So we were voicing it more to bring out the octave strings. We went with an asymmetrical bracing and voicing so we were definitely encouraging the bass side to reproduce the bass frequencies more, and the treble side to be more conducive to the treble voices, with more separation than we normally see. That was the main difference; with the DKK, we knew we could get the musicality moving up the neck and the incredible sustain in the bass, but I needed to be able to still get that without losing the ability to have the sustain in the octave strings. That was my biggest concern in developing this: that I would be able to get good power and sustain in the higher frequencies as well as the bass.

I started to realize that the reason the DKK had worked so well is that we're dealing with a similar tension as concert pitch, in fact in some cases, less tension if you go with a larger core on the strings. That's why we were so successful with the DKK. I stopped worrying about the string gauges; we'd be using some of the same ones we'd previously used. For the low F#, originally we were talking about a .066 to .070, and I remember thinking, "How is that going to be enough when going all the way down to F#,when on the DKK we used an .080?" Then I considered the differences between a 6-string and a 12-string, and I figured that we'd be at the lighter end of that, with a .072 or.074. Then I became a little concerned that some of those heavier gauges, how were we going to be able to support it? But, this was only taking into consideration the gauge, not the lowered tension with the dropped tuning. When it was all balanced out, it's not as extreme as it originally sounded. What is so scary about it, and at the same time so amazing, is that you're manipulating all of the factors that are usually taken for granted. In more standard designs, you're only thinking about a narrow range of gauges and maybe a couple of tunings on any guitar, so it's very manageable; you only have to think about a very few factors. But when you start going to gauges that are really so much heavier, you fear that the guitar is going to explode due to the extreme tensions of these heavy gauge strings! However, at such low pitches, you start manipulating the string tensions because of the dropped tuning and so forth, and this will start to balance out what was originally perceived as what would be extra high tensions. In the case of the DKK and the DKK-12, we're using what is probably the largest body size in the realm of acoustic steel string guitars. So the Helmholz frequency is easy to get into the range where we'll amplify the fundamental instead of the overtones, which can be a big problem with many of the acoustic bass guitars, for example. We had already proved with the DKK that it worked; that the frequencies at the fundamental were being amplified as we wanted; the sound was full. So for a 12-string, the frequencies would be extended higher, so what was required was a really stiff, yet extremely responsive structure for the instrument. And knowing how well it worked with the DKK, it is just an amazing instrument.

HEARING IS BELIEVING: When I first strung up the DKK-12,I immediately knew that we had an incredibly sonorous, special instrument. One of the first things I did was that I knew that Kevin would not be happy if the upper registers were not there; if it was not very musical all the way up the neck. The first thing I checked was this register and its sustain; When it was rich and full, I heaved a great big sigh of relief. I was checking the octave strings in all registers to make sure we had good sustain and my impression, once that it was all done, was that I couldn't imagine that Kevin wouldn't absolutely love it. It had such an incredible range that I was just thrilled!

Musically, it astounded me. It took me beyond what I had expected. To me, it is just incredible for me to hear really great instruments. It's always been amazing to me to listen to a wonderful guitar, because now, they almost seem to me to have more richness even than a piano. So I've come to love string instruments. But they still amaze me sometimes. One of the things I thought about when I was building this is that I knew this had to be built a little heavier. I still wanted it to have that complexity and warmth; to have goods sustain all the way up the neck, and in the higher octaves. The DKK-12 has a huge range for a single instrument, especially a stringed instrument, and not an instrument you see very often! So, it stunned me; I was really taken with the range that it has. After I heard it, I was just ecstatic about it.

It was really interesting; with Kevin's OM, we had at that point built one other guitar for Kevin. Largely, it had been what he wanted, and was happy with the instrument. Knowing what he wanted in the OM, I knew we could make exactly what Kevin had been describing to me. When the OM was finished, it was a fabulous guitar. More importantly, it was the right instrument for the right person. For me, the job wasn't done until I had heard from Kevin that it was exactly what he was looking for. That's when the passion and the work really pays off. With the DKK, this was also true; yet it took us outside the boundaries of anything Santa Cruz has done. Though baritones had been made before, what we were looking at was going beyond that because Kevin had defined very specific musical needs. He had spent a lot of time with the Santa Cruz DBB, determining what was right for him, and also what needed to be different and why. So it was different in that it was successful, yet not in the realm of what was being done. The additional challenge was that it had to be right for what Kevin was doing musically. Ultimately, with the DKK, we weren't doing anything that was absolutely ground-breaking in that there were other baritones out there, but we were doing something which broke new ground for us, with new requirements which were not there before. In other words, it may be a baritone guitar if it has a certain scale length, but this was a far stricter parameters in that Kevin's needs were very specific, so that more than just building a baritone, we were designing an instrument for a specific musical need. I knew that the DKK fulfilled the requirements for a baritone; what I didn't know is whether it would fulfill Kevin's needs musically, which as it turned out, it did. So that was very fulfilling.

With the DKK-12, we were taking it way beyond anything I'd ever heard of. The challenge seemed much more daunting, as we were trying to cover a much wider range of pitches, all with great sustain and clarity, and responsiveness. Even if Kevin had said after it was done that it wasn't what he'd wanted, I still knew that it was a great instrument, and that it had never been done before. So in that sense, it was more exciting to me, because it was a bigger challenge, it pushed the acoustic envelope much further out that what I knew had been done. Even after hearing it, and knowing I'd been successful, I was still a little hesitant because I didn't know how Kevin would respond to it. It was such a big deal to me when Kevin told me that yes, it really was what he needed. When it was done, there was a genuine surprise to me in hearing it. It wasn't a surprise in that "it actually worked," but true surprise in how beautiful it sounded. It's so stunning to me.

One cool thing about Kevin's collection of Santa Cruz Guitars is that each one is clearly made to cover a different space musically. It is clear that the inspiration for each is a clear musical need.

-Dan Roberts, July 2006

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