Valve noise

[Clive Thorne]

I am becoming increasingly aware of valve noise on my 36 key 'half decent' anglo concertina. I.e. I start to play a note and it starts beautifully, but a fraction of a second later you hear a slight 'pop' as the non-return valve on the other reed closes.  Not a great problem and I'm sure that anyone more tham half a metre away wouldn't hear it, or indeed anyone at all when playing full belt.

However it is starting to irritate me when practicing quietly (well as quiet in concertina terms, - my wife says that thhere is no such thing) and I guess that the initial loss of air would also affect the attack of the reed sounding (though I haven't found that to be a problem).

 

Any ideas? If I were to replace all the valves then how long would it be before the problem returns?.  Has anyone used plastic valves on traditional concertinas, they seem to work Ok on melodeons, and seem to retain their closed 'At Rest' position better than leather ones.

 

Any thoughts welcome.

 

[Dana Johnson]

As you say, the opposite reed valve closing is what is going on.  Under ideal circumstances the valve will lay flat in the closed position as soon as that reed is no longer sounded.  Quick note reversals will accelerate the closing but in that case, the newly sounding reed will start at nearly the same instant and cover up any slap.  It is common for valves at rest to be above the port, and will close once pressure is high enough.  This is out of sync with the reed and can be heard both as a slap and an abrupt increase in reed volume when the valve closes.  
   Changes in the weather can cause the upper surface of the valve to shrink more than the lower surface causing the valve to curve up.  Valves applied flat under high humidity conditions can raise a bit in a new drier home.  A concertina stored on it’s end will cause the underside valves of both ends eventually to curl away (these need replacing ).  For valves that are simply resting a bit high, you can usually get away with gently dragging  the back of your fingernail over the valve from glued end to tip.  This stretches the backside a little to allow the reed to lay flat again.  This may work for a long time especially if the problem is not severe.  Valves that stay significantly up after this need replacing.  
   Harder valve leather makes more noise than leather with a softer underside, though a properly flat valve will still be nearly inaudible.  The opposite problem occurs when the underside of the valve becomes the shorter surface, causing the valve to arch up in the center while touching at the tip.  This can cause the adjacent reed in that chamber to sound rough or garbled and is most noticeable at lower volumes.  This is caused by bypass air getting under the valve reducing the reed volume, but then the valve is sucked flat and the volume goes up.  The acoustic pressure in the chamber varies enough so the valve lifts in the center again, then closes, repeating the cycle at some fractional value of the reed’s pitch.  While most problematic on low reeds, I have found this all the way up to C6.  In these cases, simply holding the valve down in the center and lifting the tip to bend it up a little, will cure the problem.  On low reeds even a good flat valve can bobble up and down if it is too stiff, or too light.  Finding the right valve weight and stiffness for these reeds is not so easy.  
I find proper valving one of the more difficult parts of making the instruments.  Valves can make or break an instrument, and can be the cause of a range of problems that don’t initially seem related.

Dana

[Clive Thorne]

Dana,

Thanks for a very full reply! I will try your ideas to see if I can get them to lie flatter.

 

Did you have any thoughts on plastic valves?

 

Clive.

[dabbler]

I had this problem on my hybrid concertina.  The cause was exactly as Dana described.  I was able to fix it by gluing a thin sliver of photo negative to the valve like this.  I should have tried Dana's methods first.  Good luck!

-George

Edited January 27, 2021 by dabbler

[Chris Ghent]

Good trick dabbler. You might need to check the tuning of the reed on the other side of the pan, the one behind your valve, as a heavier valve may bring the pitch down. 

[Clive Thorne]

12 hours ago, dabbler said:

I had this problem on my hybrid concertina.  The cause was exactly as Dana described.  I was able to fix it by gluing a thin sliver of photo negative to the valve like this.  I should have tried Dana's methods first.  Good luck!

-George

Good idea. I guess it works like the thin strip of spring you get on some (older?) melodeon bass ends.

[d.elliott]

You are right to ask the question about how long before the problem returns. You need to ask yourself how the problem occurred in the first place. Usually it is about how the concertina is stored. If it is in a hexagonal box or in a gig bag where the concertina is effectively stood on its end, then that is your problem. Your new valves will not last very long. Another issue can be the valve fitting. If the valve that has the problem is the only one, then it may be that the valve has been fitted too close to the adjacent chamber wall and it is catching and being held partially open. Some chamber walls distort with time causing them to lean inwards and over the valve position. The valve may look clear when it is closed, but the clearance is gone by the time the valve is fully open. if the problem is only apparent when the concertina is played on bellows compress then odds are that you have a valve(s) catching a chamber wall

 

Or the valves may be of an inappropriate leather, old or perhaps a valve is starting to twist. 

 

The accordion reed helpers fitted to a concertina reed valve may well make it unresponsive as well as make the reed flatten as per Chris's comment above. I certainly would not fit plastic helpers to a non accordion reed design

[Clive Thorne]

Hi Dave,

 

I take your point about how it's stored - it's been mentioned many times on this site.  As it happens mine tends to get stored in playing orientation. However I was thinking about it last night, along the lines of "If the valve can move between laying flat & closed, and being open, then eventually, with a leather one, then it's rest position is almost bound to end up as slightly open."

 

The reason I asked about completely plastic valve, as per most modern melodeons, was that in my minds eye it was less likely to take a "set".

 

Another problem I have had on very few occassions is that the valve gets blown/sucked partially into the slot and then decides to stay there.

 

As Dana said it's quite a balancing act to get it right!

[d.elliott]

Valves do tend to want to stand off the woodwork slightly, but that sort of gap is unlikely to result in any intrusive valve noise, or result in valve actuation issues. If you are having problems with a valve being sucked into the reed pan vent and jamming, then the valve is wither too thin, and or too small to surround the vent adequately. Some Anglos need a heavier leather than an English treble because of the way they tend to be played, even though the note value may be the same. 

 

I have rejected batches of valves that were too hard, too soft, or cut from the wrong orientation on the skin. It is not so much a balancing act as attention detail, coupled with experience. I buy valves in batches of 200 to 300 per size and I always end up with a very small percentage of valves which I set aside to be used in more specific circumstances, or other purposes. Life gets even more entertaining when you are looking at double action big reed instruments, the bottom ends of some Duets, or English Baritones and Bass Instruments. Jeffries used square cut heavier valves than their tapered Lachenal/ Wheatstone counter parts. The square cut may have been just cheaper and because chambers were rectangular rather than segmental. 

 

You are in the UK, phone me if you want to discuss any of this further.

[Clive Thorne]

As always, this site is a wondrous source of information!!

 

Thanks all.

 

Clive.

[Dana Johnson]

Re plastic valves, advantage, predictability and stability, but compared to valve leathers,  plastics are both dense and stiff.  1 mil Mylar might work for very small reeds, but 2 mil is 2x as thick and since stiffness increases very fast with thickness, even though you can buy it in 3, 4, and 5 mill everything gets way too stiff compared to proper leather valves of the right length.  You’d need .001, .0012. .0014 etc. to give you workable gradations. I keep thinking there must be a good way to use the stuff, but I haven’t found it yet.  Leather has the advantage of working well for years when it is the right leather, thickness and stiffness.  Single thicknesses can cover a number of reed sizes and .020” and .025” -.035” gives a large range with only gradual changes, making finding the right valve easier to find/make.  It is hard to find a more perfect material than the right leather, but it isn’t always easy to find.

Dana

[Theo]

To get a better gradation of stiffness accordion valves use multi layer construction with 2 or 3 layers.  The upper layers are be made shorter and they can be shortened further to make fine adjustments to the stiffness.   

 

They do have another disadvantage of being more noisy, especially in larger sizes.  It is normal practice now among some high quality accordion manufacturers to use plastic valves for the smaller sizes and leather for the larger, or even leather with an added layer or two of plastic. 

[Chris Ghent]

There is nothing like predictability in construction materials, and valves seem to be the least predictable part of making a concertina. Accordion valves have two characteristics, one, the good one, is they have had 100 years more development than concertina valves. The bad one is they often come from more of a factory system where minor defects in operation might be ignored if they are predictable, easy to make and easy to  fit.
 

If you use the accordion valves used by top end accordion manufacturers, typically a form of leather with adjustable mylar stiffening on top, then they seem to work well. I can think of one prolific high end concertina maker who uses nothing else. 
 

I’d be interested to hear if those who maintain accordions find high end instruments with mylar stiffened valves coming in with the valves resting in a position above the reed frame surface the way concertina valves do. Theo?

[Theo]

Leather accordion valves can have similar variability to that described above by David Elliott for concertina valves. I don’t think the Mylar reinforced leather valves have been around for long to judge their stability over several decades.

[Matthew o Casey]

On 1/29/2021 at 10:09 PM, Dana Johnson said:

Re plastic valves, advantage, predictability and stability, but compared to valve leathers,  plastics are both dense and stiff.  1 mil Mylar might work for very small reeds, but 2 mil is 2x as thick and since stiffness increases very fast with thickness, even though you can buy it in 3, 4, and 5 mill everything gets way too stiff compared to proper leather valves of the right length.  You’d need .001, .0012. .0014 etc. to give you workable gradations. I keep thinking there must be a good way to use the stuff, but I haven’t found it yet.  Leather has the advantage of working well for years when it is the right leather, thickness and stiffness.  Single thicknesses can cover a number of reed sizes and .020” and .025” -.035” gives a large range with only gradual changes, making finding the right valve easier to find/make.  It is hard to find a more perfect material than the right leather, but it isn’t always easy to find.

Dana

Can leather valves be treated to revive them ? 

[Chris Ghent]

You can run something hard along the middle of them bearing down into the vent and they will appear to behave as normal but I doubt that will last long. In Ireland where there were few repairers until recently and no manufacturers I have heard people take the reed off, roll it up shiny side out and then put it back on again.  They say this lasts a while. The best (only) solution is another valve, which needs to be fitted to work similarly to the other valves on the instrument; that is, with similar “give”, in order to preserve consistent starting pressure and affect on tuning and the tone of the reed. To get this right you need access to a range of valve materials and to be very ready to say, that one is not good enough and try another. 

[ttonon]

On 1/26/2021 at 4:09 PM, Dana Johnson said:

I find proper valving one of the more difficult parts of making the instruments.  Valves can make or break an instrument, and can be the cause of a range of problems that don’t initially seem related.

Dana

Hi Dana, concerning valves and their idiosyncrasies (and I may have posted this before somewhere on this site) but there seems to be a completely different approach among bandoneon makers than there are here among concertina and accordion makers.  But first a short story.

 

I went to a Tango music performance played by an excellent bandoneon player from Argentina and an excellent piano player from Uruguay.  Afterward, I talked to the bandoneon player about his instrument and he graciously offered to open it up and show me the workings.  I immediately noticed that the leather valves were mostly all curled up away from the reed tongues.  He cautioned me not to touch them because they are supposed to be like that, though he didn't know why, and I'm wondering if anyone here can make a guess on it.  

 

The only explanation I can think of is because of the nature the way the bandoneon is played in tango music.  Every bandoneon musician I see playing tango sits with the heavy instrument on the lap, or with possible exception, stands, but now with the instrument resting on a pole to the ground.  I also notice that bandoneon bellows have a wooden frame about an inch wide mounted at their center, and I often wondered why.

 

For those who know tango music, especially traditional music, there are tremendous dynamics, with sudden explosions of sound when the instrument is dropped, then suddenly stopped by its underneath structure that supports the center piece of the bellows, with the two ends still pushing downward, causing a huge vacuum inside the bellows.  

 

My guess is that the curled up reeds prevent some of the high vacuum pressure from occurring inside the bellows by allowing some excess air flow through non-sounding reeds.  This prevents too a vacuum pressure that would tend to choke the reeds that are intended to voice.  If those reeds weren't so leaky in the first moments, perhaps the playing reeds would choke and not play at the right time.  So we want maximum dynamics in volume, but don't want to choke the reeds.

 

Regardless, I think it an interesting variation on the ideas discussed here.  

[Dana Johnson]

 

“My guess is that the curled up reeds prevent some of the high vacuum pressure from occurring inside the bellows by allowing some excess air flow through non-sounding reeds.  This prevents too a vacuum pressure that would tend to choke the reeds that are intended to voice.  If those reeds weren't so leaky in the first moments, perhaps the playing reeds would choke and not play at the right time.  So we want maximum dynamics in volume, but don't want to choke the reeds.”

 

In my experience, reeds that are set low enough to risk choking under either rapid pressure gradients or high pressure, are set too low to reach the amplitude they are capable of, though they may start at lower pressures. I don’t know if bandoneon makers use a different sort of reed plate window than is found in ordinary accordions.  The pictures I have seen look like basic accordion construction except using single plates with a whole row of reeds on them. (More like a harmonica) The pictures I have seen had valves lying flat. Reeds that are very flexible for their pitch also can choke easily, but can’t reach the volume of a reed stiff enough not to choke at its optimal set.  
   Allowing some bypass air can help avoid choking on a reed prone to it.  Noel Hill once mentioned needing to slightly feather the air valve when playing a specific note on one of his instruments to avoid it choking.  His playing can demand a lot from the reeds (and hand straps! ).  
   On concertinas, a valve that is curled a bit or just bent high, significantly affects the speed of response, as well as causing a noticeable increase in volume as soon as the valve closes.  High set reeds can also be slow to start, but the slight delay and abrupt increase in volume shortly after the reed sounds, is a dead giveaway for a raised or curling valve.
Dana