Carbon Fiber soundpost

[Allan Speers]

I recently purchased a violin made by Yasu Kobayashi.  Besides

having an internal resonator (the subject of an upcoming thread) it

has a c-fiber soundpost.

Before I comment on the sound of this violin, I'm curious if any of

you know the theoretical reasons for using this material.

[Andres Sender]

The theory is: "More is better".

[lvlagneto]

 

Is it possible that carbon fiber is lighter
than the average soundpost?  For some reason, I don’t
think so.  Perhaps it is more stable (in terms of
humidity/weather changes)?

 

The theory is: “New is always
better.”

[Allan Speers]

I can't see humidity being a factor, since wood is very stabile

longitudinally.

Maybe it really is a case of  “New is always

better.”  

-though maybe the idea is that somehow speed of transmission is

faster in CF, or there is less attenuation of certain frequencies,

or .....  (or a failed experiment,  or

...)

Prolly just a gimmick, but pretty interesting nonetheless.  As

I wrote, this violin seems extremely well-made, so I doubt the

luthier was some nut-case.  

[EarlyRetiree]

I'm too new at lutherie to experiment with things like carbon fiber --- it takes me so long to make and install a traditional soundpost. But I have wondered about several things that are considered "conventional wisdom". I'm curious to hear about the sound of this fiddle.

So perhaps the theory (and theories aren't necessarily correct) is that the composition of the soundpost doesn't matter.

[reedman]

Just guessing--carbon fiber transmits vibrations faster than wood.

[MANFIO]

It may work ok, but:

1 - it may be more difficult to cut and fit;

2 - since it's harder than spruce, it may be more prone to hurt the inside surfaces of top and back;

3 - it may be more expensive;

4 - some musicians will frown upon it.

Just my two cents.

[BarryD]

How does the violin sound??? What is your evaluation?

[Fellow]

You can charge the customer more. (between steel and wood, the solution is carbon fiber)

[Magnus Nedregard]

I don't like the idea for some of the reasons Manfio mentioned, and I would also be afraid it could move around. I can't imagine cf having just the right friction to remain in place? And what do you gain from it? Are there any advantages?

[Darren Molnar]

""""""""""""""And what do you gain from it? Are there any

advantages? """""""""""""""""""""""

Might have helped the sales. Allen, did you buy this violin because

of the unusual features , or in spite of them?

I wonder if the spruce has a sound post veneer, to protect it from

a harder sound post. If the mass of the c.f .post matches the mass

of a spruce one, I doubt that the sound would be that different. It

is all about pressure and placement, no?

I've heard of glass tues being used as sound posts a few years ago.

That never caught on, I don't think.

But if a maker does something a little out of the ordinary, and it

helps him sell a few more fiddles, and the world doesn't stop

spinning on it's axis, there's really no harm done. After all, it's

history's sober eye that separates value from gimmick.

I would not be crazy about sanding a carbon fiber post to fit

though, epoxy resin and carbon particles floating around and small

enough to breath in. Yuck.

[Allan Speers]

Magnus,  It moves arouns OK.  It seems a little bit more

sticky than wood, though, a gentle tap isn't quite enough.

Still. I manage to try it in several positions without massive

difficulty, just not as easy as moving the wooden ones.

I have NO idea what it's doing for (or to) the sound, hence my

thread.  I had hoped that perhaps some of you had tried

it.

Barry, this violin is VERY impressive sounding.  I won't say

"amazing," but then it also seems very new.  There is no date

of manufacture inside, so I have no idea, but it looks virtually

unplayed.  the seller didn't know.

So the sounds is slightly (slightly) tight and thin, like any new

violin, though the G string is loud, just not fat. I'm hoping this

will change with time.  BUT THE MIDS AND TOP AND FANTASTIC.

 This violin is very loud, and very bright, yet the brightness

is not piercing. It's more like it has a large amount of harmonics.

 This also make the violin very responsive.

[David Burgess]

When I tried it, I capped the ends with normal soundpost material.

[Magnus Nedregard]

Hmm, ok so we cap the ends with "normal sound post material" but then there's the trouble with getting your sound post setter into the cf. The obvious solution is to insert a piece of spruce in the middle sections too. Any further ideas?

[David Burgess]

I just glued a little piece of spruce on the side for the soundpost setter.

[Allan Speers]

Magnus,

I'm perfectly content if in fact this idea is only a sales gimmick.

 Just curious if you guys had tried CF.

David, what was your purpose in trying a cf sp?  What did you

hear sonically?  I assume you no longer do it, so can I assume

the experiment was a "failure?"

The slightly unique sound of this violin (which I'm loving more

every day) likely has to do with other factors, such as the

built-in resonator and slightly acute neck angle. (see my other

thread) -Or maybe even due to odd internals, as the

violin is a tad on the heavy side. It's not quite factory-heavy,

but the girl's no Kate Moss, either.

[David Burgess]

quote:

---

Originally posted by:

Allan Speers

David, what was your purpose in trying a cf sp? What did you

hear sonically? I assume you no longer do it, so can I assume

the experiment was a "failure?"

---

Just curious. No significant change in sound on this particular cello. Just a lot more labor.

Have also tried various types of carbon fiber and fiberglass reinforcements on bridges, including balsa core. Very noticeable change in sound, but can't say it was improved.

[Magnus Nedregard]

Sorry if I was a bit silly, (well I am) but it's sort of easy to make fun of new ideas in the ultra traditional violin trade. However, I haven't tried this, but I spoke to a cellist who had one installed, he later had it removed, because it didn't have any advantage to it, so he preferred to have a traditional one, in case he needed adjustments by someone unprepared for dealing with CF.

[Jacob]

"Just guessing--carbon fiber transmits vibrations faster than wood."

Is that what a soundpost does - transmitting vibrations?

[Bob A]

Have you tried swapping out the CF post with a wooden one, to explore the actual difference? Theory is fun, but reality has its benefits as well.

Resonator violin? Ever played a Strohviol?

[Mat Roop]

getting off topic but....

http://cgi.ebay.com/stroh-viol...yZ38108QQcmdZViewItem

Cheers, Mat

[robedney]

I realize that this is an old thread -- and I haven't been on Maestronet in a long while now -- but we've had an inquiry about carbon fiber sound posts specifically referencing this thread.  I thought I'd answer here and share what we've found:

 

We make carbon fiber violins, so you might assume that we'd fit carbon fiber posts.  As a general rule, we don't.  The reason -- as suggested in some of the replies above -- is entirely pragmatic.  Luthiers are well equipped and experienced in fitting/adjusting spruce posts, not so much carbon fiber.  As sound post adjustment is a key component in any good setup, it makes no sense to put an obstacle in anyone's way.  It's basically the same reason we use ebony nuts and maple bridges.

 

When it comes to the real difference between spruce and CF, in my experience there isn't any -- not that I can hear or measure.  Here's my pet theory:  The use of the sound post in violins may very well have had to do with simply keeping the top plate intact -- maintaining the arch and avoiding cracks under the treble foot of the bridge.  This is an evolutionary thing.  It turns out that the sound post -- when well fitted and placed -- also has a significant desirable impact on sound, so the adaptation persisted.

 

In my own experience (and testing) the primary (other than structural) impact of the sound post is to mechanically link the top and bottom plates.  Any effect of the sound post itself transmitting sound is drowned out by the activity of the plates.  So, so long as you make the thing out of something structurally suitable the material doesn't much matter, although the diameter does have some impact.  The fitting does matter however -- and quite a lot.

 

We do -- upon request -- fit CF posts, just as we will pressure permeate an already cut and fitted bridge with epoxy resin.  The reason here is to create an instrument that can tolerate really adverse conditions, like ridiculously high humidity, extreme temperatures/variations, or even the possibility of full immersion.

 

As a side not, if someone wants to mess around with CF posts on a wooden instrument I do suggest veneer on the sound post area of the top plate, which in my book is good standard practice anyway -- regardless of the material there is still significant point loading in that area. 

 

Cheers!

[PASEWICZ]

Exactly the same conclusion that Rene' Morel came to decades ago. There is a good story he used to tell backing up his opinion, but too long for MN.

[edi malinaric]

Exactly the same conclusion that Rene' Morel came to decades ago. There is a good story he used to tell backing up his opinion, but too long for MN.

 

Hi Jerry - try us and see :-)

 

cheers edi

[David Beard]

Brilliant. A basic problem for violin makers is our products last too long. We end up competing with ourselves and the best past makers. If we can popularize sound posts of materials stronger than spruce our products will go obsolete in just decades instead of centuries.

Not as good an obsolescence plan as spurious software and operating system updates, but it's a good start.