Harpsichord Project Part 16 - The Transposer

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ErnieM

Ernie
Corporate Member
Hi all,

While the bridges are drying out from their soaking I thought I’d take advantage of the time to take care of a few bits and pieces that need to be done. The first of these tasks involve making the instrument transposable. Ernie, what does that mean? Ok, I’ll tell you.

As you may know, all instruments are tuned to a pitch standard. Certain instruments, like the trumpet, clarinet, flute, kazoo, nose whistle, etc. have their basic pitch set at the factory when they are built. Others, like the piano, harpsichord, violin, etc. can change their built-in pitches by re-tuning, de-tuning, un-tuning, or ignoring tuning. Unfortunately, these instruments often have to play together – as in an orchestra. To do this, all instruments must be tuned to the same pitch standard. Today, in most of the world, that standard is A-440 which means that the note A above middle C must vibrate 440 times per second. The noise you hear at the beginning of every concert (yes, even rock concerts) are the musicians tuning their instruments to that standard. The instruments that can’t be tuned, like the trumpet and its brothers and sisters are already factory tuned to that pitch and can only be adjusted slightly to accommodate slight variations in the standard.

Unfortunately for us, the current standard (A-440) is a relatively recent one. Back when harpsichords were originally built the standard pitch was lower than it is now. 300 years ago, most of the world used A-415 (or something close to that) as the standard. Many instruments today are built to that standard for people who like to play this old music at the original pitch. Until recently, if the harpsichord was to be played with these old-pitched instruments, it had to be completely retuned to the lower pitch. This involved re-tuning up to 183 strings, usually 2 or 3 times, due to instability. The next day, the same harpsichord might have to play with modern-pitched instruments and the whole process would have to be repeated, this time bringing the pitch back up to today’s standard. A royal pain, to be sure. There has to be an easier way – and there is. Take a close look at the ends of the keyboard in this picture.



Notice that there is space between the ends of the keyboard and the sides of the case. The back ends of each key must be in line with the 2 strings that key will eventually pluck. It’s confession time – I misled you in the last post. We didn’t drill 102 tuning pin holes (2 for each key), we actually drilled 104. There will be two extra strings at the bottom end of the instrument that have no key with which to play them. Unless ...... we slide the whole keyboard ½” to the left. As the space between strings is ½” the bottom key will now be in a position to play these two extra strings making the top two strings orphans with no key to play them with. This is how we avoid re-tuning all those strings every time the pitch standard changes. When the keyboard is slid ½” to the left, the A key will now pluck the G sharp strings (which just happen to vibrate a 415 cycles per second). The player will think he’s playing the note A but the sound produced will actually be G sharp. This, the pitch level of the harpsichord has been transposed down to the old pitch standard. To return to the modern pitch standard, all we need do is slide the keyboard to the right ½” and the keys will now play their original strings. Pretty neat, huh? Does this mean the player has to carry a ruler with him to measure the ½” distance he needs to slide the keyboard. No – there’s a better way. Here’s how we do it.

Traditionally, a wooden block is inserted at each end of the keyboard to fill the space between the end of the keyboard and the case side. What we’ll do is make 3 wooden blocks instead of two. One of these 3 blocks (called Cheek Blocks for reasons only Ima and Yura know) will be exactly ½” wide. As there is 2 ½” combined space between the two ends of the keyboard and the case sides, the remaining two blocks will each be about 1” wide. These two 1” wide blocks will be screwed to the sides of the keyframe and move with the keyboard when it’s slid. The ½” wide block is attached to nothing – it is removable. To play at the old-pitch, the player removes the ½” block, slides the keyboard as far as it will go to the left, and inserts the ½” block into the ½” space left at the right end of the keyboard. To return to modern-pitch, the player removes the ½” block from the right end of the keyboard, slides the keyboard as far as it will go to the right, and inserts the ½” block into the ½” space now at the left end of the keyboard. That’s all there is to it. Let’s build the blocks.

The cheek blocks will be 2” high so we’ll start by gluing up 3 pieces of ¾” poplar.



When the glue has set, we slice the blank apart into two 1” wide pieces and one ½” piece.



At this stage, the blocks will work fine but look rather plain. Let’s fancy them up a bit. First we’ll glue a ¼” cap to the front of each block to hide the edges of the 3 plys they’re made out of.



Next we’ll cut a ¾” high x ½” deep rabbet to allow the front edge of each block to fit over the case front molding. Behind the rabbet and 45 degree angle is cut to make it easier to remove the keyboard and cheek block from the case.



Now we’ll use some of the same molding we used on the top edges of the case and some poplar stock the same thickness as the molding to decorate the tops of each cheek block.



Here’s a photo of the 3 cheek blocks after the moldings have been glued on and trimmed.



The outboard rear edges of the two wide cheek blocks are rounded to avoid accidentally damaging the case when the keyboard is removed or replaced.



Next, the two wide cheek blocks are screwed into place at each end of the keyboard.



Here’s the keyboard installed in the case in the modern-pitch position (keyboard slid to the right). Note the ½” removable cheek block on the left end.



Here’s the keyboard installed in the case in the old-pitch position (keyboard slid to the left). Note the ½” removable cheek block on the right end.



One thing left to do. In the next photo, notice the space between the top surfaces of the keys and the nameboard. This space will be filled by a thin strip of wood called the Nameboard Battan. This is where the builder’s name goes.



The Nameboard Battan is 1 ½” tall and about ¼” thick. A decorative edge has been routed into its top front edge.



And finally, everything is installed into the case. The Nameboard Battan will be screwed to the bottom of the Nameboard after the keys get their keytops installed to make sure there is enough clearance between the keytops and the bottom of the battan.



And that’s all you ever wanted to know about a Harpsichord Keyboard Transposer – probably more.

The bridges are still drying from their soaking so next time we’ll cut up some ebony and bone and install keytops onto the keys.
One final note – putting links to previous parts of this Project has become a problem in several ways. Bas has come up with a great solution. For the next 300 posts in this series (I’m just kidding – I hope) I’ll include a link to a file that contains the url’s for all parts of this series for those of you who want to refer to them.

Till next time,
Ernie
 

Travis Porter

Travis
Corporate Member
Ummm.....


Why are you soaking the bridges? Don't they run straight?

Did you cover making the keyboard? I don't seem to remember it.
 

ErnieM

Ernie
Corporate Member
Hi Travis,

No, the bridges that will be glued to the soundboard curve and roughly follow the outline of the bentside of the case. While they could be bent dry while gluing them down, it's much safer to soak them. Then they're temporarily nailed down to the workbench in the proper curve and allowed to dry. The springback that occurs when the nails are removed pose no problem as they are close enough to the right curve to bend safely.

As for the keyboard, we built it in the first three parts of this series. It does seem like a long time ago but it was only 9 weeks ago. Here's some links to the keyboard construction.

Part 1 - The Keyboard
Part 2 -Keyboard con't.
Part 3 - Keyboard con't.

Thanks for following along with me.

Ernie
 

Travis Porter

Travis
Corporate Member
Ernie, have you considered submitting all of this content for a magazine article? It is very well written, documented, and photographed. It is as good or better than a lot of what I read.
 

ErnieM

Ernie
Corporate Member
Ernie, have you considered submitting all of this content for a magazine article? It is very well written, documented, and photographed. It is as good or better than a lot of what I read.
Travis,

I've thought about writing a book on the subject but I doubt there would be enough folks interested in it to make it publishable. In 1980 a book called "Harpsichord Design and Construction" by Evan Kern was published and it was my introduction into harpsichord building. Things have changed a lot since then and a more updated book could be useful.

As for a magazine article, I never considered the possibility. I think there's already over 300 photos in this project and we're not nearly done. I don't think any mag would devote the space required to make sense of it all.
Then again, who knows what the future will bring.

At any rate, thanks for those kind words. I was a teacher for 34 years and its nice to know I can still communicate something clearly.

Ernie
 

mlzettl

New User
Matt
Ernie,

As usual, your workmanship is remarkable, and the documentation of this project is absolutely first class. But what is truly fascinating to me is that we get to learn not only about how a harpsichord is built, but also something about music as well. That's one of the things that has always impressed me about musical instrument makers - not only do they have to be superb craftsmen, but they also have to know something about the history of the instruments they're building, and they have to be able to play them, at least to some extent, as well.

This thread alone is reason enough to join this site.

Happy New Year.

Matt
 
M

McRabbet

Matt, I couldn't have said it any more eloquently! This series of threads is a masterpiece and Ernie as builder and author has made it most enjoyable for all to read as this project progresses. I am looking forward to the phase where Ernie's wife begins her part, one step at a time.

I find this particular thread very intriguing and I must ask Ernie if he devised this very slick method of changing key. An elegant solution, indeed.
 

ErnieM

Ernie
Corporate Member
I find this particular thread very intriguing and I must ask Ernie if he devised this very slick method of changing key. An elegant solution, indeed.
Rob,

I sure wish it was my idea but the truth is I'm much better at inventing problems than finding solutions. This method has been around for several years and I've used it on my last five or six instruments. It's even retro-fitted on existing harpsichords that don't have it. In this case the top (or bottom) note is lost because there are no extra strings to accommodate the shift. Small price to pay if someone really needs to play at different pitch levels.

Glad you're enjoying my mumblings - only 299 posts to go. :rotflm: :rotflm::rotflm:

Ernie
 

ErnieM

Ernie
Corporate Member
Matt,

I'm flattered by your remarks although I doubt that I truly deserve them. You said something that interests me

That's one of the things that has always impressed me about musical instrument makers - not only do they have to be superb craftsmen, but they also have to know something about the history of the instruments they're building, and they have to be able to play them, at least to some extent, as well.
How people end up doing what they do has always interested me. I think what you say about instrument makers is true in most fields. People gravitate to what they like and have an aptitude for. Some of us are lucky to be able to do what is interesting to us. I'd bet that the many talented furniture makers on this site know as much (probably more) about the furniture that they build as I know about harpsichords. The variety of products that can be made out of wood amazes me as does the talent of so many people to do what they do. We may play different games but we're all in the same playground.

Ernie
 

clowman

*********
Clay Lowman
Corporate Member
Ernie.. you have no idea how impressed I am. I am just completely blown away. Not only is your craftsmanship superb ... you also know alot of "why things are done this way". There are 2 goals I have hope to achieve WWing. One is build a Grandfather clock. A very nice one. And the other is a really nice musical instrument. I'm afraid, you are way out of my league.
 

ErnieM

Ernie
Corporate Member
There are 2 goals I have hope to achieve WWing. One is build a Grandfather clock. A very nice one. And the other is a really nice musical instrument. I'm afraid, you are way out of my league. __________________
-Clay
Clay,

I was just about your age when I built my first harpsichord. I was "out of my league" then too. If you want to build a musical instrument - do it! You may be surprised to learn that you're not as far "out of the league" as you think.
To be frank, my first instrument was terrible - and I loved it. I learned an awful lot by building it - mainly I learned how much I needed to learn. Then I went out and learned it. Ask for help from those who may know more. I've never met a real pro who hesitated when asked for help from a serious beginner. I can't tell you how wonderful the feeling of accomplishment is when you've built something that someone can actually play. Go for it.

Ernie

P.S. I'd love to build a grandfather clock too. Wish I knew how.
 

Shamrock

New User
Michael
Fantastic and educational too. I played the sax in high school and remember tuning every day before class, but no one ever explained the tuning standard. Thanks for the info-now I can impress somebody with this bit of info at the next concert I attend!


Keep it coming


:BangHead::BangHead::BangHead:clamps-clamps-why do i never have enough clamps
 
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