Same Reeds For Push And Pull

[aPeacefulWarrior]

Wow, in another post something was mentioned about a concertina that uses the same reeds for the push and pull. This really got me curious, so I started experimenting with it. I actually came up with something that worked and was amazed at how simple it is.

 

I don't know if this sort of thing is common knowledge or not among builders, but I can understand why it's not used often. It takes up about the same amount of space as having 2 reeds(maybe more space?). And also, the push and pull seem to have two distinctively different tonal qualities(although that might be fixable).

On the other hand it may have some advantages, such as having half the amount of reeds to retune.

 

Eitherway, it was interesting to experiment this and it feed my curiousity.

I can post more info on this if anyone is interested.

[Chris Timson]

My understanding as to why two reeds are used instead of one is the horrrible graunching sound you get when you change direction on the same button. How do you overcome that?

 

Chris

 

PS the advantage it would have would be half the reeds to make! That would be an enormous saving in time and cost.

[JimLucas]

I can post more info on this if anyone is interested.

Well, I'm interested. And I'll bet I'm not alone.

[Howard Mitchell]

My understanding as to why two reeds are used instead of one is the horrrible graunching sound you get when you change direction on the same button. How do you overcome that?

Chris,

 

I've played an instrument that has only one set of reeds and a valve arrangement so that the air always flows in the same direction through the reed.

 

Although there were several leaks in the air chambers it was possible to change directions whilst playing the same button with little if any noticable change in the sound. The inertia in the reed means that it carries on playing during the momentary drop in pressure. I didn't detect any graunch!

 

Jesse has emailed me privately for more information about this instrument. I'm working away from home at the moment and playing at Sidmouth all next week. I'll try and revive the phographs and diagrams and put them on a website as soon as I can.

 

We're going modern at Sidmouth as those nice people at Orange have put me on the trial of their new 3G Mobile Office Card which means I'll be able to stay in touch as supersonic speeds.

 

Howard Mitchell

[Richard Morse]

My understanding as to why two reeds are used instead of one is the horrrible graunching sound you get when you change direction on the same button. How do you overcome that?

There have been accordions made which have reeds that operate when air comes from either side. No fancy valves and convoluted air paths, in fact the reeds themselves had no valves (doesn't need them, of course!). There was no discernible difference in tone or response on either push/pull, and no "graunching sound".

 

Despite having only half as many reeds one would think that the box would be lighter/smaller/and possibly cost less.... Everything was "standard" sized most likely due to that the reed plate had to be large enough to accommodate the convoluted air bleed that allowed the reed tongue to start in either direction. This made the single reed/plate assembly the same size as a typical double reed - or at least close enough that they made it the same so that they could use the same reedbanks, action mechanisms, etc.

 

Those reed assemblies were also quite complex which probably made them more expensive. While I couldn't find fault in the way it responded/sounded, I wonder if it didn't catch on primarily because it was substantially more costly than typical reeds.

[A.D. Homan]

Despite having only half as many reeds one would think that the box would be lighter/smaller/and possibly cost less.... Everything was "standard" sized most likely due to that the reed plate had to be large enough to accommodate the convoluted air bleed that allowed the reed tongue to start in either direction. This made the single reed/plate assembly the same size as a typical double reed - or at least close enough that they made it the same so that they could use the same reedbanks, action mechanisms, etc.

 

Those reed assemblies were also quite complex which probably made them more expensive. While I couldn't find fault in the way it responded/sounded, I wonder if it didn't catch on primarily because it was substantially more costly than typical reeds.

 

 

Hi Rich,

 

I just read in some French accordion magazine that someone in France has been working on perfecting the 2-way reed, and it corresponds exactly to what you said. In the picture, the plate looks just as wide as a 2-reed plate. It also looks more complex to build, just like you said. So now that I read your post, I'm wondering what is "new" about this one that the magizine was covering, since from your post I gather that this has been around for some time. (It was discussed as the invention culminating from decades of a sideline hobby-research by a French professor, an engineer I believe -- the irony is that the guy personally plays diatonic boxes, so it won't benefit him personally! I guess it could cut down on the number of reeds to tune in a huge CBA.)

Also of note: I believe that the reeds in the khaene and sheng also work in both air directions?

-Andy

[Stephen Chambers]

... now that I read your post, I'm wondering what is "new" about this one that the magizine was covering, since from your post I gather that this has been around for some time.

It is covered in Charles Wheatstone's 1844 patent.

 

I believe that the reeds in the khaene and sheng also work in both air directions?

 

They do indeed, but for very different reasons: The traditional oriental free reed is integral with its frame, three sides of its shape being cut in that same piece of metal, with which it is flush (it has no "set", above the frame, like its western cousin). It is mounted in a bamboo pipe which forms a resonant chamber, being tuned to the same note as the reed, but provided with a fingerhole to break this accoustic link, the reed only sounding, on blow or suck, when the hole is covered.

[Howard Mitchell]

I've put a set of thumbnails which you can click to get full size images of the Blue Meany on my web page.

 

You can get to it via http://www.hgmitchell.co.uk - click Concertina then Blue Meany or go directly to http://www.hgmitchell.plus.com/hgm/bm/thumb.htm

 

Howard Mitchell

[Richard Morse]

I just read in some French accordion magazine that someone in France has been working on perfecting the 2-way reed, and it corresponds exactly to what you said. In the picture, the plate looks just as wide as a 2-reed plate. It also looks more complex to build, just like you said. So now that I read your post, I'm wondering what is "new" about this one that the magizine was covering, since from your post I gather that this has been around for some time.

The accordion I examined/played that had the two-way reeds was built around 1940.

[JimLucas]

So now that I read your post, I'm wondering what is "new" about this one that the magizine was covering, since from your post I gather that this has been around for some time.

Maybe it's new to the person inventing it, because (s)he is unaware that it was previously invented? That can happen, even with professional patent searches. If you had just thought up Wheatstone's English concertina keyboard layout, and you asked a non-British patent researcher to find out whether it was truly new, what are the chances that he would turn up the original Wheatstone patent?

 

A recent example of this was Göran Rahm discovering that the Hayden duet layout had been invented much earlier (I can't find a date at the moment) by Kaspar Wicki. But Brian Hayden didn't know this, and apparently no one discovered this when he applied for his patent. Brian didn't become aware of it until after his own patent had expired. Not knowing of the Wicki system, Brian's work was indeed his own innovative creation, even though it was somebody else's, first.

Edited July 29, 2004 by JimLucas

[aPeacefulWarrior]

The blue meany is very interesting...

Took me a minute to figure out the diagram, but I think I see how it works.

 

I think my design is more simple. It works, but I haven't been able to test it enough(and not in a concertina) to be able to tell you how well. I will try to post a diagram soon.

Edited July 29, 2004 by aPeacefulWarrior

[Stephen Chambers]

Maybe it's new to the person inventing it, because (s)he is unaware that it was previously invented?

I think the key word in Andy's post is "perfecting", the person in France doesn't appear to be claiming to have "invented" the concept :

 

I just read in some French accordion magazine that someone in France has been working on perfecting the 2-way reed

 

Cheers,

[ttonon]

No fancy valves and convoluted air paths, in fact the reeds themselves had no valves (doesn't need them, of course!).

 

Rich, do the reeds you refer to work in conjunction with one-way valves, or is there a double-acting feature designed within the reeds themselves? Can you please explain more detail, or provide a picture?

 

I have a patent for a very simple reed design, what I call a "furcated reed." I don't have a picture of this design on my web page, but those interested can go to www.uspto.gov and do a simple search for Patent Number 6,143,968, with title: Method and Apparatus for the Vibration of Reeds. (Inserting the given number into the simple search box will work, then click on the "images" button.) I will also attach a Word file with some images, but I don't know for sure if this will work.

 

I can explain verbally how this reed works as follows. As most of us realize, the tip of the Western free reed tongue rests in an offset position, slightly out of its slot. Air must pass through the slot from the tongue side in order to start vibration. The furcated reed tongue has two tips, with each tip connecting to a common metal strip that's riveted to the reed plate. One of these tips lies on one side of the slot, and the other lies on the other side of the slot. Thus, air from either direction can start the reed. I've also extended this idea to include multi-furcations (along with bi-furcated, tri-furcated, etc.) in the reed tongue. Along with the obvious features of bi-directional airflow, the elimination of leather valves, and the ability to maintain vibration during a change in airflow direction, there are, I believe, additional advantages to such designs, including a sound spectrum different from that of conventional reeds. This spectrum is also somewhat more amenable to alteration, by alteration of the tongue/slot features, and may add varying degrees of tone color, depending on vibration amplitude. I refer you all to the patent for more text and visual detail. I must say that I've had time to build only a couple prototypes, which worked reasonably well, though have not yet satisfied myself as to how true these claims are, but I think the design is notable because of its simplicity.

 

Best regards,

Tom

http://www.bluesbox.biz

[Richard Morse]

Rich, do the reeds you refer to work in conjunction with one-way valves, or is there a double-acting feature designed within the reeds themselves?  Can you please explain more detail, or provide a picture? 

No valves. The trick is that the reedplate is an assembly of 3 thinner plates. There are slit-vents on either side of each side of the outer reedplates that direct air to suck down (and start) the reed tongue which is installed in the exact center of the center reedplate.

 

I've made a diagram of that bit I can't seem to find it at the moment. I'll look for it when I get back this afternoon.

 

I have a patent for a very simple reed design, what I call a "furcated reed."

Verrrrry interesting! Congradulations! What pitches did you create? I wonder if this type of design will be good only for certain pitch ranges. It may be that there could be some problems with higher reeds being too stiff to operate or lower ones being wonky due to limted plate parameters.

 

That double acting reeded accordion I had mentioned used those special reeeds only from about the F below MC to the E three octaves above MC and I'm wondering if there may be a similar issue at work here. Their solution and yours are similar in intent (reed tongue/air direction) but opposite in execution (theirs with two "vents" and yours with two "reed tips").

[ttonon]

I've made a diagram of that bit I can't seem to find it at the moment. I'll look for it when I get back this afternoon.

 

Rich, I'd be very interested in seeing this diagram.

 

Verrrrry interesting! Congradulations! What pitches did you create? I wonder if this type of design will be good only for certain pitch ranges. It may be that there could be some problems with higher reeds being too stiff to operate or lower ones being wonky due to limted plate parameters.

 

They were approximately around A3 (about 220 hz). As I'm sure you can appreciate, it would take a fair amount of time and effort to explore the full range of frequencies. As explained in the patent, the furcated idea can be executed in a multitude of ways, with a considerable number of design parameters, and at the present time, I'm not able to adequately explore this technology. Perhaps in the future I can do it justice.

 

Best regards,

Tom

http://www.bluesbox.biz