Sign in to follow this  
H.R.Fisher

wood selection

Recommended Posts

  I am curious as to how much the selection of tone wood is attributed to the sound of an instrument.I'm especially referring to the choice of the spruce top. I am aware that there are multiple pieces,parts and  methods that contribute to the final tone. Considering all things being equal how much of the pie would be attributed to the choice of wood?    Thanks,  Henry

Share this post


Link to post
Share on other sites

I will be very interested to read the other responses, Henry.  It seems to me this is a moving target because of all the other variables in play.  A "good" piece of wood, properly carved, may be only as good as other elements being in the range of quality.  Lots of folks have ideal wood characteristics for which they look and they vary quite a bit.  But I think few would disagree with the notion that attributing to wood a percentage of the impact of the various components on the sound is not possible.  That said, lots of MNers probably would be comfortable ranking wood selection among the variables contributing to sound.  

Judging from your previous posts that I have read, I'm not saying anything you don't already know.  But one never knows who else may be reading...B)

By the way, where in central PA?   I grew up in Lewisburg -- about an hour and a quarter roughly north of Harrisburg.

Share this post


Link to post
Share on other sites

After you acquire the skills needed to avoid mistakes and settle on the model, arching style and varnish you are going to use then the wood becomes the largest variable. You can make good violins out of any reasonable quality wood but great instruments require great wood.

Share this post


Link to post
Share on other sites
58 minutes ago, nathan slobodkin said:

You can make good violins out of any reasonable quality wood but great instruments require great wood.

Sounds exactly like something Sam Z. said to me.  I don't disagree.

Share this post


Link to post
Share on other sites
4 hours ago, nathan slobodkin said:

After you acquire the skills needed to avoid mistakes and settle on the model, arching style and varnish you are going to use then the wood becomes the largest variable. You can make good violins out of any reasonable quality wood but great instruments require great wood.

Then remains the question .. Nathan, what would you consider to be great wood?

Share this post


Link to post
Share on other sites

Strong and light with distinct summer and winter grain and at least some shading. Grain spacing can vary but any variability of grain within the piece such as wider at the edges should be gradual and consistent. There is a certain feel of nice wood under the gouge which is hard to describe but I guess I would say dry and punky is not good. Lastly I would say the cutting is probably more important than the wood itself. OK wood cut well can make good violins, great wood cut badly is useless.

Share this post


Link to post
Share on other sites
19 minutes ago, nathan slobodkin said:

 OK wood cut well can make good violins, great wood cut badly is useless.

Reminds me of another quote, not sure who I heard it from:  "You can make a bad violin from good wood, but you can't make a good violin from bad wood."

That's what I had in mind when I started out making instruments... to use the "best" wood.  With visuals aside, that meant high stiffness/weight, and low damping, based on general acoustic theory.  Density seems to be size-related, with larger-bodied instruments benefiting most from the ligher plates, and not so much for violins.  Still an experiment in progress.

Share this post


Link to post
Share on other sites
9 hours ago, nathan slobodkin said:

 You can make good violins out of any reasonable quality wood but great instruments require great wood.

 

8 hours ago, Don Noon said:

Sounds exactly like something Sam Z. said to me.  I don't disagree.

There would remain the question : Which kind is the difference between "good violins" and "great violins" ? 

 Great violin = good violin + additional power for soloistic usability  ?       or rather more 

Great violin = good violin ( having enough power for soloistic use ) + additional quality of sound-colour and additional amount of expressive possibilities ?

What is concerned in higher extent by mediocre wood : sound-colour or power ?

My personal suspicion : you can find a wood with good split / high RR / high- soundspeed and in spite of all having an even "bad" wood in some cases ( that e.g could mean, at the very beginning you yet don´t like to hear the knock-tones of the raw wedge and finally you wouldn´t like the sound-colour of the finished violin ).

 

5 hours ago, Emilg said:

Then remains the question .. Nathan, what would you consider to be great wood?

 

45 minutes ago, Don Noon said:

...to use the "best" wood.  With visuals aside, that meant high stiffness/weight, and low damping, based on general acoustic theory.

The first thing would be easy to control - however damping is difficult to measure, depends on the measured mode and its shape, frequencies of modes etc. .... What one could use for damping - measurements of raw wedges ? At the best a 2-0 mode, which is a low mode - eventually not representative for middle and higher frequency - damping, which probably is much more important.

So the trend remains : measured is ( and used for comparisons ), what is to measure easily but not measured is ( and not used for comparisons ) , what is to measure only with high difficulties but probably would be very important.

Share this post


Link to post
Share on other sites

Ok thanks, so high RR and low damping comes close to great wood. These factors can me measured.

But now a question that has been bugging me ever since a started making guitars 10 years ago, and now even more with violins.. can wood have a certain quality, let's call it x-factor that cannot be measured, but can be heard or even felt in the sound of the instrument? I guess i'm asking for gut feelings now ..

Share this post


Link to post
Share on other sites

In the near future I think we'll see what the wood properties are in great violins.  The procedure will be to do a high resolution CAT scan of a violin to get the exact plate geometries; a modal analysis will be done, and then a finite element analysis model will be made with the geometry and guesses for the wood properties. Many iterations of the FEA will be done with successive different material property guesses until all the predicted mode frequencies converge and match what the real ones are.  

The capability to do this already exists.  It hasn't been done because it requires a lot of effort and there's no money to do it.

I'll gamble and bet that the great violins were made with rather ordinary wood.

Share this post


Link to post
Share on other sites

Marty, there WAS an attempt to do all that with the Titian not too long ago, with FEM and adjusting wood properties to try to match the known mode frequencies.  The results were more than dubious, in my mind.

But we do have some indications of wood properties right now, from plate weights, taptones, and signature mode frequencies.  Curtin had an article on that.  Nothing appeared to be extraordinary, although perhaps maybe "good" in the way of wood properties.

However, damping is rarely addressed, and difficult to measure.  Bissinger attempted such measurements, and as I recall, the conclusion was that internal damping was nothing unusual, but somehow more sound was produced... something similar to what I recall Schleske observing.  Physically, this doesn't hang together in my mind, and something is missing.

Share this post


Link to post
Share on other sites

OK, let's get real. What can you do at a VSA show to select the best wood? Do you go into the sales room (or into the forest, or a lumber mill) armed with a computer and test equipment? You are stuck with the purchased wood.  However, if you get a sample to evaluate later with the ability to purchase more of that log, you can accumulate quality wood. Kevin Prestwich sold me sample billets. I then ordered more of what I liked. I am happy.

BTW, I am convinced that the wood quality is the limiting factor. 

Share this post


Link to post
Share on other sites

And what about spruce species.. i remember Michael D. wrote years ago that in his experience Sitka and Engelman were lacking in certain tonal qualities that European spruce from the Austrian Alps did have. Is there any truth to that? Marty, Don, or Michael?

Share this post


Link to post
Share on other sites
14 minutes ago, Don Noon said:

Marty, there WAS an attempt to do all that with the Titian not too long ago, with FEM and adjusting wood properties to try to match the known mode frequencies.  The results were more than dubious, in my mind.

But we do have some indications of wood properties right now, from plate weights, taptones, and signature mode frequencies.  Curtin had an article on that.  Nothing appeared to be extraordinary, although perhaps maybe "good" in the way of wood properties.

However, damping is rarely addressed, and difficult to measure.  Bissinger attempted such measurements, and as I recall, the conclusion was that internal damping was nothing unusual, but somehow more sound was produced... something similar to what I recall Schleske observing.  Physically, this doesn't hang together in my mind, and something is missing.

I very much agree that something is missing.  

I'm beginning to feel that too much emphasis has been on violin's sound character and not enough given to playability issues. Great players want several things but many studies have concentrated on only the easy things to measure.  It's easy to do measure a violin's sound spectrum and to do listening tests for liability or projection in halls.

On the other hand it's expensive (laser vibrometers, impact hammers) to do admittance tests and minimum & maximum bow force tests that relate to how difficult it is to play an instrument or mold the violin's sound. The results of those kinds of studies then have to be related to the violin's structure for us makers.

 

I thought Pyrkosz (1) was making real good progress but unfortunately he graduated and took a job completely unrelated to violin research. That's a problem--there's no money in doing violin research.  Much of the work is done by graduate students or professors and there's only a few of them in the world interested in violins.  The students go on to other things and the professors are retiring.

 

1.  "Reverse Engineering the Structural and Acoustic Behavior of a Stradivari Violin",  Michael a. Pyrkosz, 2013, Dissertations, Master's Theses and Master's Reports, Michigan Technological University

Share this post


Link to post
Share on other sites
2 hours ago, Emilg said:

can wood have a certain quality, let's call it x-factor that cannot be measured, but can be heard or even felt in the sound of the instrument? I guess i'm asking for gut feelings now ..

Gut feeling?.... That x factor is called a virtuoso player.

We all can't agree on the ideal wood, because the trend these days is for 'projection' which to me means a brighter tone. You can get that from high density spruce, but low density spruce produces a darker tone. Is there an ideal mixture of properties that produces both qualities?

Share this post


Link to post
Share on other sites
6 minutes ago, sospiri said:

Gut feeling?.... That x factor is called a virtuoso player.

We all can't agree on the ideal wood, because the trend these days is for 'projection' which to me means a brighter tone. You can get that from high density spruce, but low density spruce produces a darker tone. Is there an ideal mixture of properties that produces both qualities?

From the 7 classical guitars i built, #2 had that x factor.. even when i played it :lol: So there may be more than one x factor coming from player, bow, species, age, etc.

Roughly, there were 2 camps of classical guitar making when i was building and reading about it on forums. One camp was going for that old world sound (Torres, Hauser..) and one camp was going for the new and improved big sound, strong projection with lattice bracing and double tops. I really prefer the old world sound, maybe they were not as loud as the lattice braced ones, but had more warmth, depth and sweetness.

Share this post


Link to post
Share on other sites
1 hour ago, Emilg said:

And what about spruce species.. i remember Michael D. wrote years ago that in his experience Sitka and Engelman were lacking in certain tonal qualities that European spruce from the Austrian Alps did have. Is there any truth to that? Marty, Don, or Michael?

From purely measurable properties, there is such wide variation that there is a lot of overlap.  On average, Engelmann tends to be the lightest, and Sitka the heaviest, with European in the middle.  I haven't made a serious instrument from Sitka yet, but for similar densities, I haven't noticed any obvious differences between Engelmann and European. If you're used to medium density European, and try to do something with low-density Engelmann, you probably wouldn't like it.

Share this post


Link to post
Share on other sites
2 hours ago, Emilg said:

Ok thanks, so high RR and low damping comes close to great wood.

I don´t know, if that ever was proved. But it seems to be the normal assumption.

2 hours ago, Emilg said:

.. can wood have a certain quality, let's call it x-factor that cannot be measured, but can be heard or even felt in the sound of the instrument?

Yeah, this is a fine name :  x - factor !    I absolutely believe in your factor and in the ability to hear it. My belief is, that the ability to hear it in a raw spruce or maple - wedge decides much about the rank, a maker can achieve.

x- factor could be the sum of all, exceeding our quite naive "understanding" of wood, which is nearly completely reduced to simple taptones/RR/density/weights/some few of the big number of wood-e-moduli . The complete x-factor participates in shaping sound and therefore can/could be heard - but only with great difficulties in the raw wedges, which naturally produce a sound, very much differing from the sound of the much thinner final plates. Who masters the transformation between both, may be could have one of the most important gifts to become one of the great makers.

 

Share this post


Link to post
Share on other sites
14 minutes ago, Don Noon said:

From purely measurable properties, there is such wide variation that there is a lot of overlap.  On average, Engelmann tends to be the lightest, and Sitka the heaviest, with European in the middle.  I haven't made a serious instrument from Sitka yet, but for similar densities, I haven't noticed any obvious differences between Engelmann and European. If you're used to medium density European, and try to do something with low-density Engelmann, you probably wouldn't like it.

Ok so probably apart from the differences in density there's not much difference in tonal aspects between spuces

Share this post


Link to post
Share on other sites
15 minutes ago, Danube Fiddler said:

I don´t know, if that ever was proved. But it seems to be the normal assumption.

Yeah, this is a fine name :  x - factor !    I absolutely believe in your factor and in the ability to hear it. My belief is, that the ability to hear it in a raw spruce or maple - wedge decides much about the rank, a maker can achieve.

x- factor could be the sum of all, exceeding our quite naive "understanding" of wood, which is nearly completely reduced to simple taptones/RR/density/weights/some few of the big number of wood-e-moduli . The complete x-factor participates in shaping sound and therefore can/could be heard - but only with great difficulties in the raw wedges, which naturally produce a sound, very much differing from the sound of the much thinner final plates. Who masters the transformation between both, may be could have one of the most important gifts to become one of the great makers.

 

So if the x-factor is the sum of all known and unknow quantities, beginning with great wedges till good setup, it's just a matter of finding all those sub-x-factors and perfect execution. Easy enough! :D  It seems many are trying but looking at the wrong places, so excluding those can help (things like tuning the sp, etc.) Anyway, as the OP is about wood selection: i'll start paying extra attention to the spruce first (starting soon for #6).

Share this post


Link to post
Share on other sites
21 minutes ago, Michael_Molnar said:

I have yet to receive spruce from Europe with density under 0.4. Maybe it's bad luck. 

European spruce can be  quite heavy. I have a stock of 0.29 sg eurospruce, which i would consider not usable for violin tops. So there are sources for light european spruce. Maybe I send you a few <0.4 pieces some time ;)

 

 

General question: How important are the acoustical properties for the top VS back? I have the 'gut feeling' that the top should be much more important but I am not really sure about that.

Share this post


Link to post
Share on other sites

Could depend who you buy it from. The spruce (7 tops) i got from Drewbas (Poland) was all 0.38-0.40, but 2 sets from Romania were 0.44.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.