A few design and construction decisions. I decided to put three bars under the soundboard, as you can see. The reason, initially, was simply to make it stiffer. Given that, I decided to copy what I've seen in some existing harpsichords, as far as the locations; I would not have dared to put bars under the bridge, otherwise. This barring is somewhat similar to some Italian harpsichords. The suggestion is that it leads to a brighter tone with more upper harmonics. Which is what I want; the evolution of the piano has been away from the extremely bright tone of the harpsichord; later generations of the piano have added more and more felt to the hammers, producing a dull, muffled tone -- unless the keys are played quite hard. The velocity-dependent tone-colour change of the modern piano is an interesting effect, but it always seems to leave me with the wrong tone at the wrong volume level: I want bright, trebly, delicate tone colour even when I play soft -- especially when I play soft, in fact. So, my pandalon will have hard wooden hammers, not covered with felt or leather; when a more muted tone is desired, there are two stops available to muffle the tone: the moderator and the buff. The moderator puts some kind of cloth or leather in between the hammers and the strings; so the effect is similar to having the hammers covered with the same material. The buff presses cloth or leather up against the strings, near their ends; so the sustain duration of the string is reduced, unlike with the moderator.
Anyway; my soundboard-barring is total guesswork, slightly-informed by some things I've seen. But I'm guessing that my motivations and approach are quite possibly very similar to those of the Original Builders, inadvertently. Bars were surely put across soundboards first for simple structural reasons, and then adjusted and repositioned to optimize the sound, once their inevitable effect on the sound quality was noticed.
And then, there's the matter of my sound holes. I hadn't been planning to have two, but as I began to dry-fit the parts together, I saw that the main internal diagonal brace creates an almost-complete partition of the soundbox, into two distinct regions. So I put a hole on each side of the partition, positioned and sized by more "intuitive guesswork".
By holding down the edges of the soundboard against the frame, I can approximate the tone it will have when glued into place. Tapping the soundboard all over its surface shows me that it is nice and "lively", and seems to have a good tone as far as bass and treble balance. (I am no expert, however.) I am glad to find that both sound holes seem to "do something", in that the sound changes noticeably when one or the other is covered up by my hand; they both radiate sound, for taps occurring anywhere on the surface. These are good signs...
My "mitre guide" turns out to be the best tool for just about every occasion, anymore! Here, it helps me trim the wrestplank ends. Later, I have started to use it to help me "machine" the sides of the frame; progress is slower than I ever expected for these operations (I thought I'd figure out some way to use power tools), but results are accurate.
There's the trimmed wrestplank, resting in the (untrimmed) frame. You can perhaps see from my Sharpie-markings on the wrestplank, the four-octave band of strings will leave a fair bit of width on either side, unused. I could extend the bass and/or the treble by several notes, if I wanted to. However, I'm not especially eager to have higher notes than what I've planned; of course I'd take more bass, but the current bass limit (E2) is derived from the case length and the need to use iron strings to work with a pickup. Someone who didn't care about the pickup could add some deeper bass notes using brass wire.
But basically, my conception for this is 4-octave (49 notes). I'll build some bigger, 5-octave instruments, using what I learn here; a harpsichord, and who knows, perhaps a bigger pandalon as well. (The additional notes will mostly be in the bass, probably at least down to F1 instead of stopping at E2.)
Here I am setting up the saw-guide for trimming the frame. Basically the whole perimeter of the frame needs to be sawed flat, to make smooth vertical faces to which I can attach the outer case walls. This is usually done with powerful (electric) machines these days... With the dainty little teeth on my Buck Bros. PVC pipe saw, I can chug along at, probably, 10cm per hour or so, on average. This step, more than any of the others so far, is the one where I become quite committed to this particular frame! No more thoughts of maybe it's too messed up and I should start over with different lumber. Nope, as of now, I'm all in. (Hearing that the soundbox "taps well", is probably another thing that makes me ready for "committment" with this frame.)
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