Chamber Tuning

[Chris Ghent]

From Neil Wayne's treatise on Wheatstones

 

"as early as 1838, most of his concertinas had at least three or four of their smallest reed chambers fitted with a cork cross-piece to adjust the volume of the chamber and to 'tune' it to the resonant frequency of the reed within the chamber..."

 

Has anyone seen this, or even better, does anyone have a photo of this..?

 

Here is the complete paragraph...

 

"It was Charles Wheatstone's research on the acoustical linkage of tuned pipes and chambers with metal free reeds in 1828 and 1830 that led to the introduction of tuned reed chambers into his firm's concertinas, and By the 1850s this practice had spread to over half of the reed chambers in each pan, and by the 1880s reed pans were being produced with every chamber fitted with a wooden cross piece to tune it to the reed. A surprising confirmation of this acoustical enhancement can be heard if all the reeds are removed from such an acoustically tuned concertina: when such a reedless instruments is 'played', the hissing and rushing of the air through the empty reed chambers can be heard to produce a fair approximation of the notes or scale being played! The practice of using these cross-pieces to tune the reed chambers appears to have continued both at the Wheatstone factory and at Lachenals and other rival makers right up to the 1930s."

 

The complete work is at http://www.d-and-d.com/contributions/tina-history.html

 

Best wishes

 

Chris

Edited November 1, 2007 by Chris Ghent

[Larry Stout]

Four chambers on each side have such cross pieces in my 1851 Wheatstone treble. My slightly earlier baritone does not have them-- but that may be because it is a baritone. Here's a picture of the reed pans of Wheatstone 2667 (from 1851).

 

[Greg Jowaisas]

Chris,

I have a number of instruments from the 1800s both Lachenal and Wheatstone with this treatment. In many cases it is a raw cork barrier with no chamois. I'll try and take a photo or two later today.

 

Nice pic, Larry.

 

Greg

[chris]

Hi

reed pan of a Joseph Scates 32,New Bond Street, (not mine but similar)

chris

 

 

 

 

 

 

 

 

[synchopepper]

Love those crosspieces... the blocked end of one of the chambers on my 1880 era Lachnal New Model extended treble was an exact fit for a high reed I removed to make an air button and provides a perfect long term storage location where it will not get seperated from the rest of the reed set!

[Robin Harrison]

I was curious about this to recently.

If you do a site search on Tuning Chambers, there a lot of stuff.

Cheers Robin

www.concertina.net/forums/index.php?showtopic=6107&mode=threaded&pid=57622

[Chris Ghent]

Thanks for the pics everyone. I was interested to see what was meant exactly because the written description gives an impression of precision chamber tuning.

 

Chris

[ragtimer]

Thanks for the pics everyone. I was interested to see what was meant exactly because the written description gives an impression of precision chamber tuning.

Here's a photo of the same principle applied to accordion reeds in stand-on-end cells, from my Bastari Hayden Duet bandoneon-concertina. You can see in the cell where the reed has been removed, that the cell is deliberately padded to jsut barely clear the end of the reeds. This is the highest treble row of reeds.

 

I assume these chambers were shortened to the minimum like this, in order to prevent stray resonances that might color some notes to sound different from their neighbors. On my simpler Stagi 46, some notes do indeed sound more flute-like, probably due to such resonances strengthening a certain harmonic.

 

--Mike K.

Edited November 5, 2007 by ragtimer

[Henrik Müller]

... in order to prevent stray resonances that might color some notes to sound different from their neighbors. ...

That I can buy - I have trouble buying this:

 

'tune' it to the resonant frequency of the reed within the chamber

 

In my world, that gives us a sine wave (depending on how strong the resonance is). Sine waves are boring.

But fiddle with the chambers to get rid of, say, an annoying 4th harmonic - that sounds reasonable.

 

On some of the old instruments you can hear some very strong "different-from-all-the other-notes"-notes.

Example: Put Disc 2 of "Anglo International" in you player and play track 5, Kate McNamara, "The Bees Wing"

- the G on her Jeffries has overtones which really stick out from the rest of notes.

 

/Henrik

[Chris Ghent]

I assume these chambers were shortened to the minimum like this, in order to prevent stray resonances that might color some notes to sound different from their neighbors. On my simpler Stagi 46, some notes do indeed sound more flute-like, probably due to such resonances strengthening a certain harmonic.

 

My interest in the original quote was because it seemed to indicate there would be clear evidence of a way of thinking; that it would be obvious the chambers were tuned. My interest waned when I saw the tuning implements were what I would describe as ordinary chamber shortening divisions. The reason I think them ordinary is because when you look at a reedpan full of them they usually have one thing in common. They have been inserted at the first possible point past the end of the reed shoe. This to me means that rather than fine tuning for resonance or harmonics removal they were designed to make the chamber as small as possible, and the drive to do this is need for speed not tone.

 

The original quote goes on to add "...A surprising confirmation of this acoustical enhancement can be heard if all the reeds are removed from such an acoustically tuned concertina: when such a reedless instruments is 'played', the hissing and rushing of the air through the empty reed chambers can be heard to produce a fair approximation of the notes or scale being played!" In the absence of written confirmation or scientific testing this is not evidence for acoustical enhancement. it is speculation. For example it could also be a side effect of the chamber lengths now reflecting the length of the reed shoes, which naturally get longer as the note deepens. For further evidence against acoustical enhancement, imagine the effect of having a chamber tuned precisely for a note; what would be the effect on the note on the other side of the reedpan, which is rarely the same note in an anglo? They can be up to a fourth apart.

 

Chris

[ttonon]

In the absence of written confirmation or scientific testing this is not evidence for acoustical enhancement. it is speculation. For example it could also be a side effect of the chamber lengths now reflecting the length of the reed shoes, which naturally get longer as the note deepens. For further evidence against acoustical enhancement, imagine the effect of having a chamber tuned precisely for a note; what would be the effect on the note on the other side of the reedpan, which is rarely the same note in an anglo? They can be up to a fourth apart.

Chris

 

Hi Chris,

 

I totally agree with your statements, and I can just add more detail. I think it's safe to say that it's not possible to tune all the cavities of a concertina to the FUNDAMENTAL of their corresponding reeds - even for an English, in which each cavity accommodates two reeds of the same pitch. It may be possible, however, to tune most of the cavities to some overtone of the associated reeds, but for the lower notes, the reachable overtones might be too high in pitch to be heard very well. In any event, one might argue that the "hissing" heard in the quoted claim is due to the cavities emphasizing some range of overtones. But I doubt even this is the case. Another complication is the fact that cavity tuning can be attempted by altering several geometric parameters, not just cavity length or volume. So, I guess one might argue that there are many tuning features that cannot be seen in the pictures. I still doubt this is the case, and my feelings are that such a uniformly tuned instrument would be no small accomplishment. Subsequent cavity tuning for other (similar) instruments would be much easier, though such instruments appear to be quite rare. Finally, in my experience, a cavity tuned to the fundamental would probably choke the reed, preventing it from speaking. As I mention in the related paper that I wrote, there may be advantages to tuning cavities to certain overtones, but the rewards at this time do not appear to justify the necessary work.

Best regards,

Tom

[Dana Johnson]

In an interesting side note, the (ancient and modern ) chinese Sheng uses pipes that are tuned to the fundamental of it's free reeds which differ only slightly from western reeds in that they are cut from the plate and have zero set. they are affixed at the bottom end of the pipe which has a small hole in the side above the wind box to destroy the resonance. To play the reed, you stop the hole with your finger reestablishing the resonance and the reed jumps to life. Here though even the highest reeds easily equivalent to a high english reed. ( can't remember the high note on a treble )have tubes that measure in inches, nothing like the tiny chambers of a small concertina reed and the medium notes are vastly longer than the longest low duet reed chamber. Each reed is double acting with no set, but require the resonance to start. Very cool instruments still popular in modern traditional orchestras. There are also free reed flutes called Bawu's that have similar reeds cut in the reed plate but have a set. they are played in the overblown mode ( high pressure ) and have a single reed that responds to all the fingerings of the flute. Here the reed is coereced ( and can be played on the draw as well as blow, but not as easily ) by the higher pressure and doesn't really follow the same physics as a normal free reed which are determined by air flow forces, mass and stiffness. It behaves more like a pressure controlled valve similar to a clarinet or double reed type instrument.

Here's a link to a quick pic I googled:

<http://www.paulnoll.com/China/Music/mus-sheng.html>

Edited November 8, 2007 by Dana Johnson

[ttonon]

Hi Dana,

 

I also find the Asian free reeds fascinating. I particularly like the sound of the bawu, though I hadn’t realized that its reed has a set. The instrument is also interesting in that the shape of the tongue is triangular, and like a flute and clarinet, its tube is cylindrical. But since the reed is mounted near the closed end, it’s not surprising that its sound is reminiscent of the clarinet. Yet, I think it also can sound flute-like. I think the free reed used in this way – with a resonator - can be more expressive, with much more sound complexity, than the way we westerners use it in our instruments. The tubes of the sheng are conical in the region where the reed is mounted, and no doubt this feature helps explain it’s characteristic sounds – quite sophisticated for an instrument that goes back, they say, 3,000 years, and is, perhaps, the first, real, musical instrument. There are numerous videos on Youtube that one can enjoy, and the following two are very interesting. The first is that of a sheng solo, and the second is that of a bawu, with poignant interest in particular to those of you in England, and in general to all westerners.

 

http://www.youtube.com/watch?v=GndoDa0nBl0

 

Best regards,

Tom

[DMQuinn]

I studied the sheng and bawu while living in Taiwan, and accumulated a good few of both. Here is a link to an Imagestation album of photographs of several types of sheng

 

Sheng

 

and another which shows some close-up shots of the reeds from bawu and hulusi

 

Bawu and hulusi reeds

[ttonon]

I studied the sheng and bawu while living in Taiwan, and accumulated a good few of both. Here is a link to an Imagestation album of photographs of several types of sheng

 

Sheng

 

and another which shows some close-up shots of the reeds from bawu and hulusi

 

Bawu and hulusi reeds

Thanks for making these very interesting photos available. How much effort have you put into learning how to play these instruments? Particularly with the bawu, do you play western music with them? It seems you also play pipes. How would you compare playing the bawu with playing the pipe cantor?

 

Best regards,

Tom

[DMQuinn]

Thanks for making these very interesting photos available. How much effort have you put into learning how to play these instruments? Particularly with the bawu, do you play western music with them? It seems you also play pipes. How would you compare playing the bawu with playing the pipe cantor?

 

Best regards,

Tom

 

I worked on the sheng very seriously, and was the only westerner in the municipal trad orchestra in the city I was living in. (That actually says more about how desperate they were for sheng players than about how skillful I became.) I was only playing Chinese music in that context, although I did get to the point where I could knock out a good few ITM tunes on the sheng.

 

The bawu was more of a curiosity for me. It's not much like playing an uilleann pipe chanter, in that the fingering is "open," and there is considerable dynamic range on the bawu. I suppose there are similarities to the Northumbrian smallpipes chanter, in that it plays only in one register. The bulk of the traditional music for the bawu has a fairly small compass, generally not more than a tenth or so, but like the NSP chanter, there are keyed versions which extend the range by adding tone holes above and below the fingered range.

[Lawrence Reeves]

David, nice to have you on board.

[Guest Peter Laban]

Although he wasn't around this year, a man playing the sheng has been coming to the Willie Clancy week for the past ten years or so. He usually plays in the street. Absolutely gorgeous player of Irish music, interesting enough he attract a lot of the old local players who think he's brilliant. Gussie Russell was enthralled by his music. Have loads of pictures but not readily printed.