May 25, 2008
The two latest cellos I made were made as copies of a 1616 Brothers Amati cello, please see "Previous Workshop Photo Diary" for photo diary description of the first iteration of this process. After completing the first cello as a copy for the owner of the original, I decided, because of the successful sound of that cello, to make it again for the next customer. Both of those cellos seemed to offer a certain unique voice character, which struck me as a bit different from my own Wiebe pattern cellos.
There are actually very few Bros. Amati cellos extant. Several colleagues have told me that there are maybe only four of them in the world. I can't verify that but I think it is accurate. In early 2007, the cello virtuoso, Jian Wang gave a master class for cello students at Bard College, right across the Hudson River from us here in Woodstock. The setting was the wildly original Frank Gehry designed Fischer Performing Arts Center. Jian Wang was sitting at the edge of the stage and the student who was playing for him sat right across from him. We, the small assembled audience, were seated on a short riser towards the back of the stage. The reason I describe this entire scenario is that when Jian Wang demonstrated certain passages from whatever piece each student presented [and which he did entirely from memory], the sound of his cello was clearly bouncing off the far back wall of the hall. The character of the sound of his cello, in his hands, was massive, robust and a deep baritone. Hearing that sound made me, as a professional violinmaker, covet that sound which I strive to instill in my own cellos.
Jian Wang [who has a cello of mine from several years ago] was given the use of this Amati cello as part of the package of having been asked to be the cello recording artist for Deutsche Gramaphone. He generously allowed me access to his Amati cello to take tracings, measurements, and photographs.
With the full outline tracing in hand, I wondered what a viola of this outline might look like, and,... ultimately how it would sound. I reduced the cello outline to a viola size of 16 1/4" and studied it for some time. Finally a commission presented itself which offered me the opportunity to try out the idea of making a viola from a reduction of this magnificent cello.
Once fully "fleshed out" on a paper cut out, it became apparent that the proportions which worked superbly well for a cello, were not surprisingly slightly ill-suited for a viola. The main thing was that the lower corners were actually a little too high up in the outline. Looking at the photos, the white paper outline of the first image shows the straight reduced outline of the cello with provisional F-holes drawn in, which shows the lower corners too high for successful string crossing with the bow on a viola. The next image is a foto of the actual original cello which shows how successful the outline appears in its original full size configuration.
For practical purposes, I lowered the lower corners to make it more feasible to play this outline as a viola, as illustrated in the photos of the second white cut out paper outline. And finally, I include two photos of an actual Brothers Amati viola from 1619, which came into the shop for a little work thus allowing me the opportunity to document all of its physical characteristics with measurements, tracings, and photographs. This viola was probably a very large viola originally and cut down,... maybe, as just a guess, around 18" or more in body length. To make it more playable, the upper and lower bouts were drastically cut down to create a new 16 1/4" outline but the C-bouts and corners were left original full size. This disparity of upper and lower bouts proportionate to the C-bouts seemed to easily endorse my license to enlarge the C-bouts of the reduced cello outline by lowering the lower corners, which at that, still created C-bouts smaller than the cut-down Bros. Amati viola, in which the couple of photos of it illustrate the difference. The difference in distance between the upper and lower corners of actual Bros. Amati viola and my "composite" Bros. Amati viola is a whopping 10 mm!
Starting the Viola
When the outline drawing has been finalized, a pattern is made and from the pattern, a form is made. The rib assembly of the viola is built around the form, thus establishing the physical outline of the paper in 3D wood. The form material itself is only plywood in this case, a fixture utilized to hold the instrument's ribs in place for tracing onto the back and top plates. Once the ribs are bent and glued to the corner blocks in the form, willow linings are added to reinforce the outline.
The back and top woods are selected for the sound concept and the appearance. For this viola, I had Amati instruments in mind and chose spruce with a grain spacing that was not too close. The grain spacing on this spruce is extraordinarily even all the way across and is made from old, specially selected Englemann Spruce which I obtained from the forrester myself probably about 25 years ago. I decided it would benefit the appearance of this outline and arching to make a one-piece maple back, which I also acquired from my wood supplier about 20 years ago. It features a wonderful fanning out of the flames on the back, which I believe will add some visual drama to this viola, as you can see in the fotos below.
With the rib assembly finished, its outline is traced onto the top and back, these plates are cut out and prepared for roughing out the archings. When first roughed out, the appearance is very crude and rugged looking. Thereafter, finger planes are employed smoothing the surface to create the fundamental arching contours.
The archings are structurally crucial to the voice of the instrument. In Part 3, I will show the finished archings and talk about them.
The rise and fall of the curves of the arching are truly some of the most enchanting and mystifying elements of violin family instruments. I believe that the foundation for the character of the sound of an instrument is laid when the arches are created. It could be argued that the archings may be the single most important factor in creating the character of the sound of an instrument. Naturally, it is not realistic to pursue that very far because of course, the selection of the wood, the choice of the outline, the thickness graduations of the back and top and the entire finish setup with the adjustment are also all very important factors. The success of an instrument is entangled in every great and small feature, none can singled out as "the" most important.
What might be a safe statement is to say that the making of the carved arching is pretty much only in the purview of violinmakers and those who make viols. Many other crafts and disciplines utilize skills and methods in common with violinmaking but the arching is singularly relegated to violin family instruments.
To make the arching for this composite Bros. Amati viola, I had to refer to the documented examples in the materials provided by the great British violinmaker, restorer, and expert, John Dilworth. It was necessary to make arching cross section templates in order to try to imbue this project with authentic Amati concepts. The tracings that were made available to me included three Brothers Amati violas of varying sizes: One was quite large at 17 3/4" body length, another was too small, a gorgeous uncut 15 7/8", one was almost exactly the right size at 16 3/8". From this tracing, I was able to get most of the cross sections for the back but only two for the top. I recreated the shape for the remaining top cross sections by comparing the ones from the larger and smaller violas and finding a middle line version, which did look quite authentic comparing it to the ones on the other size violas.
At first I had wondered if, as the outline had done, the reduced cross section arching contours of the full-size cello might make appropriate templates but again, it appeared that the proportions of the reduction did not produce the right shapes for a viola.
In the first photo of this series, the arching of the back is being carved with fingerplanes. Next to the back, lying on the bench, some cross section arching templates can be seen. These are held up to the arching at specific locations to check for accuracy and maintain the correct shape in going for a Brothers Amati arching, as they guide and dictate the process.
The following photo images show the finished archings, after they have been shaped with the finger planes and scraped smooth. As is typical for me, although I considered them "finished", after these photos were taken, I did a fair amount more of necessary refinement with the escrapers on the archings.
The shaping of the inside archings of the back and top plates is as important as the outside archings and as important as the thickness graduations. The manner in which the thicknesses are arranged, by way of the corresponding outside and inside arching shapes, will directly affect the success of the sound of the finished instrument. Consequently, this is a point at which a great deal of care must be taken.
In the first photo, a "map" of the arrangement of the thicknesses can be faintly seen as drawn on the inside of the back. The arrangement of thicknesses is quite different for the back than for the top. There is a wider spread of measurements, ranging from around 4.7 mm in the center of the back to around 2.7 mm in the upper and lower areas. The measurements of the top are more uniform ranging from around 3.2 to around 2.5 mm. During the process as the plates near completion, a lot of time is taken to check frequently about the stiffness and flexibity of each plate as it proceeds towards its ideal dimensions. I also listen to the tap tones and record all of those when the back and top are finished. The second photo shows how the inside of the top looks when it is finished. The top is yet to receive its F-holes and bassbar before being called finished but the back is nearly finished when the inside is completed. Both the back and top will get the edges rounded.
Occasionally we joke around in the workshop about how procrastination pays off [since clearly it usually doesn't]. As discussed in Part 1 of this diary, I arrived at this version of a Brothers Amati viola by reducing the outline of an original Bros. Amati cello but I was pretty sure that the cello scroll, however, would not reduce appropriately. As I worked on the body of the viola, I kept wondering what I would have to do to arrive a good scroll pattern for this viola. Then I had the unexpected pleasure of a genuine Brothers Amati viola come into the shop, from which I was able to take tracing, measurements, and photographs in order to eventually make a copy of it. The net result of this was that I was able use the photos of the original Bros. Amati viola scroll for the scroll of my "composite" Amati, giving it a welcome boost in authenticity.
As I have done before, I used an actual size photocopy of the photo of the scroll and glued it directly to the block of wood from which I would make the scroll. The photocopy then became the template for this scroll which allowed me to produce a scroll that would be very close to an original. The remaining photo images in this series are of the scroll after it has been band sawed out of its scroll block.
Part 5 will describe the method of producing an appropriate F-hole pattern for this viola so please come back to find out about that.