Low reed stall

[Waldo]

I have noticed that when playing a sustained low treble note, while accompanying with the left hand, that the low treble note stalls (goes quieter or pulses) in time with the bass notes. What's happening is the air pressure is changing due to the bass pallets opening and closing, resulting in an oscillating treble note. Is there a cure for this outside of increasing the bellows pressure (and resultant volume) or adding registers to mask the pulses? It's mostly noticeable on the lowest notes and when playing softly.

Thanks and Press on...
Waldo

 

[debra]

I'm afraid this is mostly "the nature of the beast". The bass notes indeed change the air pressure, unless (and this is very difficult) you compensate by pulling/pushing harder on the bellows during the bass notes to compensate. In theory you can compensate so that the (low) volume of the treble note stays constant but this is hard. Sound volume is not constant when you apply constant force to the bellows but to keep the treble note constant when you add additional notes (pressing a bass button) you must apply more force to the bellow to keep the same pressure at that treble note.
Note, it is increasing the force on the bellows, not the bellows pressure (as you said). This requires a lot of practice and intimate knowledge of how your specific instrument behaves.

 

[Geronimo]

Im afraid this is mostly the nature of the beast. The bass notes indeed change the air pressure, unless (and this is very difficult) you compensate by pulling/pushing harder on the bellows during the bass notes to compensate. In theory you can compensate so that the (low) volume of the treble note stays constant but this is hard. Sound volume is not constant when you apply constant force to the bellows but to keep the treble note constant when you add additional notes (pressing a bass button) you must apply more force to the bellow to keep the same pressure at that treble note.
Note, it is increasing the force on the bellows, not the bellows pressure (as you said). This requires a lot of practice and intimate knowledge of how your specific instrument behaves.

Well, lets try to move on to what we can actually do. The thing to note is that constant air pressure is the key to constant volume. Also, the bellows pressure is force per cross section. The only thing missing in that equation is that some of the force to the left instrument half does not arrive inside of the bellows but is invested and regained accelerating and decelerating the left side of the accordion against its inertia. Now the effect is larger when the left half is heavier and its harder to control when the bellows is travelling faster. Its actually part of what gives leggiero on the accordion its pizzazz: since the bellows continues moving after ending a tone, the next tone will start on increased pressure, giving the next note a slight accent at its start.

So what does that mean for playing technique? Time for developing a bunch of imagery inconsistent with reality (singing pedagogy does that all the time to reasonable success). We want constant pressure inside of the accordion, so we put an imaginary balloon inside filling it that we are embracing (backstrap helps keeping the balloon from bulging outside of our reach). Embrace that accordion and feel the pressure of its inner balloon in your arms. Yes, the instrument interferes: basically your arms have to eavesdrop inside. And you need to feel that pressure in your arms, not fingers: you need the fingers for playing, for deliberate phrasing and articulation, so pressure is transferred via palm and back of left hand and general posture: fingers have nothing to do with it.

Then you must be up to the challenge of delivering the additional air that the bass reeds swallow. Basically the bass notes cause large air leaks which you compensate for, keeping the pressure in your balloon by providing the additional air leaking in or out.

Maybe practice just playing some legato melody while willy-nilly pressing the air button. Thats actual an exercise that diatonic players will have little problem with because their instruments already require using the air button for air management as they dont have the luxury of having everything written with equal amounts of push and pull. So just playing on non-chalantly while secretly letting significant amounts of air in or out is what they are used to doing.

Inertia does make trouble at the start and end of bass notes but the start of a bass note, assuming that the reed has reasonable response is a moment of change helping to mask slight bumps in volume. And we can try ending bass notes a bit sofly rather than with an abrupt stop of air flow. So while it is a very hard challenge to record only the right side and have that appear smoothly while playing the left side, in practice we dont have that challenge. Not in full extent, anyway. So in practice we get away reasonably well just compensating for the air leakage of bass notes without trying hard to figure the inertia/bounciness of the left accordion halfs weight into it. But at least our imagery is concerned about the accordions inner balloon rather than the outside of the instrument, so it tries telling us how the directness of our feeling for the pressure is affected by it.

 

[Waldo]

Thanks for that perspective. I'm going to work on it, but I think it's beyond my skills at this point. I will log the info and try to work it into my learning.
Waldo

 

[debra]

Thanks for that perspective. Im going to work on it, but I think its beyond my skills at this point. I will log the info and try to work it into my learning.
Waldo

Try it at somewhat higher volume first. Play a waltz rhythm combined with whole-measure melody notes. When you pull constantly on the bellows the melody notes will sound a bit like aaahaaahaaa: you hear a change in the note each time you press a bass button (base note or chord). Now try to move the bellow pressure up while you press the bass button until the melody notes start sounding like aaaaaaaa without any volume change.

 

[Waldo]

Paul,
The issue was first noticable during your "constant" reference. I'll try to modulate the bellows to compensate. There are so many little details one needs pay attention to when playing these things, it requires a certain mastery of a detail, to where it becomes automatic, before another can be addressed with any hope of improvement.
In my former life, I provided training in Emergency Management of Crisis Events. Hazardous materials spills, forest fires, earthquake aftermath, etc. One major element was "span of control". How many responsibilities can one person assume before management of those responsibilities suffer? The answer: THREE. Because of this knowledge, I have tried to limit/restrict my focuses until I'm comfortable with them. Obviously, there is plenty of overlap to go around.
I often dedicate a practice session to something new, without practicing any of my normal routine. I'll schedule some work on this soon because the aaahaaahaaah is so annoying.

Press on....
Waldo

 

[debra]

Paul,
The issue was first noticable during your constant reference. Ill try to modulate the bellows to compensate. There are so many little details one needs pay attention to when playing these things, it requires a certain mastery of a detail, to where it becomes automatic, before another can be addressed with any hope of improvement.
...

I mostly play in ensembles/orchestras, and then the problem of interference between treble and bass side vanishes because only the treble side is used. We can fade out a single low note perfectly as there is no bass side to interfere with the airflow or pressure. Solo players have a much more difficult life...

 

[Geronimo]

I put up a demonstration video here. I did use some dynamics compression because otherwise the voice would have been just too quiet in comparison with the louder passages but the respective reaction times were set to be slow enough that they should not have affected the sound continuity too much. I chose to call the compensation of air usage pressure management since air management was already taken for not trying to run out of bellows space.

 

[Waldo]

Geronimo,
Thanks a lot for the video, picture worth 1,000 words and all that. While I had a hard time pickng up my particular problem from the first "tune". The second was exactly on the mark with low tone treble button being held down while several bass notes were played. I was able to see how you were maintaining the pressure.
I find this issue most intrusive and difficult to handle when playing slowly and (most importantly) at low volume, when adding bellows also raises the volume noticeably. Could you address this specific condition (low volume) with another video? I find I like messing around with the low treble notes and tend to ignore the bass side when noodling around, because of the reed stall.
Thanks for the help,
Waldo

 

[Geronimo]

Geronimo,
Thanks a lot for the video, picture worth 1,000 words and all that. While I had a hard time pickng up my particular problem from the first tune. The second was exactly on the mark with low tone treble button being held down while several bass notes were played. I was able to see how you were maintaining the pressure.
I find this issue most intrusive and difficult to handle when playing slowly and (most importantly) at low volume, when adding bellows also raises the volume noticeably. Could you address this specific condition (low volume) with another video? I find I like messing around with the low treble notes and tend to ignore the bass side when noodling around, because of the reed stall.

Well, I probably would have needed to play more from Jalousie because there are quite a few passages where one can play low volume. Now I am not particularly sure what you are aiming to see: the problem with the video is that it shows the result of maintaining the feeling of constant pressure with the left hand much more than it shows the act. Its not as much I plan to move this amount to maintain the same volume as it is Ill maintain this amount of pressure independent from how much the bellows happen to move. Which is a lot when a single chord button triggers 22 notes...

Now admittedly my instrument makes this approach of controlling pressure rather than speed comparatively natural when playing on a single reed on the right as there is almost no bellows movement at all anyway. Its also kind of unusual as it reacts kind of benign at low volumes since the bass goes down gracefully when starving it of air: that makes this brutally unbalanced registration work out less awful than one should assume. Ive played with other instruments where the bass reeds were sounding more according to their pitch-dependent maximum potential and balancing the bass sound with simple registrations of the treble was rather more dissatisfactory.

So while I can show you that this works at rather low volumes as well, you dont actually see why, and particularly at extremely low volume the combination of my instruments bass dying in a graceful manner and the treble just sticking around may create an unrealistic impression.

Ive tried just stuffing a blood pressure meter around my left hand but the air bulge just wanders back and forth and the pressure does not actually correlate with the actual pressure transferred to the bellows. Pity: was a droll idea.

 

[Waldo]

G-mo said;
"Now I am not particularly sure what you are aiming to see: the problem with the video is that it shows the result of maintaining the feeling of constant pressure with the left hand much more than it shows the act."

In your video, I was able to see the technique and tie it to the resultant sound. Per my original post, it was the pressure variation I was looking for in the vid. The bigger "exit window", a result of several bass buttons depressed at the same time, would require a faster/larger stroke of the bellows in order to maintain a steady pressure within the instrument,. Your demo illustrated that perfectly, to me. By watching what's going on (the vid) and hearing the result, I can envision whats going on mechanically (creating the sound). I then can work on recreating both.
As noted before, it's the low volume/low note condition that is the most glaringly ugly when the held treble note warbles with the bass action.
Here's another variable that may be having an effect: My main box is small. The bellows measures a diminutive 13 x 7 inches [330 x 175mm]. Perhaps, the small bellows volume has a harder time keeping up with the demands of the reeds, whereas, a full size bellow would compensate with slower/less movement, thus keeping the reed tongue moving.
I'm also going to pay more attention to the application/release of the buttons, both sides. I can see there is a lot of expressive possibility available in both that and "variable" bellows movement. Like the bow on violins strings.

Thanks for all the input

Press on....
Waldo

 

[debra]

...
Heres another variable that may be having an effect: My main box is small. The bellows measures a diminutive 13 x 7 inches [330 x 175mm]. Perhaps, the small bellows volume has a harder time keeping up with the demands of the reeds, whereas, a full size bellow would compensate with slower/less movement, thus keeping the reed tongue moving.
...

Bellow size should be pretty much irrelevant for this issue. Smaller bellows just means it will open (and close) faster to move the same amount of air. But in terms of maintaining pressure it should not matter. If anything as the movement of the bellow is faster it may be easier to maintain the pressure, but also this may not matter either.

So sorry, I dont think you can blame the difficulty on your specific instrument. Its a generic difficulty, nature of the beast as they say, and it just requires a lot of practice to master.

 

[jozz]

if you have a little air leakage will this issue be less?

 

[debra]

if you have a little air leakage will this issue be less?

Yes, because then adding another leak by pressing a bass button makes less of a difference than when there is no initial air leakage. Its all about the difference in air pressure caused by pressing bass buttons so the more air pressure and air flow already used the less the influence of opening another hole.

 

[Geronimo]

G-mo said;
Now I am not particularly sure what you are aiming to see: the problem with the video is that it shows the result of maintaining the feeling of constant pressure with the left hand much more than it shows the act.

In your video, I was able to see the technique and tie it to the resultant sound. Per my original post, it was the pressure variation I was looking for in the vid. The bigger exit window, a result of several bass buttons depressed at the same time, would require a faster/larger stroke of the bellows in order to maintain a steady pressure within the instrument.

Well, thats basically what I mean: you make it sound as if I move the bellows faster in order to compensate for the larger air use of the bass buttons. But its sort of the other way round. The bellows move faster as a consequence of me maintaining constant pressure (or force) on the bellows. The result should be the same if you blindfolded me and pressed the bass buttons without me expecting it. The result will likely be wobblier without me anticipating it, like someone catching his balance when you push him unexpectedly is not the same as the regular maintenance of balance when, say, playing volleyball and rushing left and right according to ones own plans.

But principally, the mechanism is supposed to work autonomically even if it can respond more smoothly to the effects of intentional actions.