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[Sage Herb]

Oh come on, Chris!  The only thing that makes me feel my age is when the kids at work call me "young man" (now in my sixties).  There's nothing wrong with a fellow netter promoting you to consultant - probably correct in context!
Rob.

I make no comment on the substance of this exchange but, for the record, the Mr/ Dr distinction does not signify consultant/ other status. Rather, in the UK, the convention is that a medic who has qualified as a Fellow of one of the Royal Colleges of Surgeons is referred to (in formal situations) as 'Mr' or 'Miss' X. S/he may or may not have attained consultant status. In non-surgical specialties, 'Dr' would be customary, irrespective of consultant status. (There is a long history to this, which I won't take up readers' time with, except to say that red-and-white striped poles are involved......)
Cheers
Steve

[jerfish]

Of course here in the united states Dr. is a title from physician of any specialty with or without fellowship (yes I understand there is quite a difference in post graduate training sequence and titles in the UK and elsewhere), to podiatry, optometry, PhD, to rug cleaning "the rug doctor", "tree surgeons", etc...

Many people out of the UK are unfamiliar with the Mr./Dr. distinction in the UK (including those in the medical field in the USA) and what it means.   It was proper of you to be direct with your desires for referencing. 

Let's just say I quite feel it is overused over here. But now I feel quite off topic, and as I use the Melodeon to forget my occupation and relieve Emergency Room stress, I'll stop mixing the two. 

[Grape Ape]

Sorry Chris,
I meant no disrespect, quite the contrary in fact.

[Theo]

Getting back on topic...

Reeds vary in their stability.  Some drop noticeably when pushed harder and this may be related to how far the pitch can deliberatly be bent.  The factors which make a reed more unstable are:  lower pitch, shorter scale length and thinner profile in the central part if the reed.

Harmonica reeds have much shorter scale length (reed tongue length for a given pitch) and are much thinner, and are more susceptible to pitch dropping when played hard.  I've learned this from my attempts to tune harmonica reeds. 

[Chris Ryall]

Some of my middle notes'll bend whereas their neighbours won't. All of the really low ones will do it. I guess the randomness in mid range might relate to various scratches made by various tuners during their lifetimes?

[ to our friend GA. It was actually several others had Mr'd sarcastically, there on 'search' if you want to be bored]  Chris

[Theo]

The point I was trying to make really was that perhaps notes where the pitch naturally drops with increasing pressure might be easier to bend.  The pitch/length/thinness things was just to add some pointers as where those unstable reeds might be found.   Preciosa reeds for example are relativly unstable under pressure compared with full size Hohners.

Chris do you see any evidence of pitch dropping under pressure on the notes you can bend?   I'm not taking about big changes here, maybe just a dip of 5 or 10 cents?

[Chris Ryall]

All my kit is packed in the car I'm afraid, Theo. Off to Belgium and beyond. I melnetted in because my son has cadged a lift, and is now late for departure! 

Will do the experiment after Gooikoorts festival.  I'll have nothing to do except to enjoy the pleasures of  Alsace () I 'think' the iPad has an FFT programme ...

[jerfish]

Forgive my beginner question, but Can you really break the reeds doing this?

[Theo]

I don't think anyone really knows. What is certain is that after long hard playing some reeds will break, but most will not.  So if you want to try it I don't think you are putting the reeds at significant risk.

[jerfish]

I don't think anyone really knows. What is certain is that after long hard playing some reeds will break, but most will not.  So if you want to try it I don't think you are putting the reeds at significant risk.

Thanks!  I'll "gently" experiment

[Chris Ryall]

It's a bit like extraction corks from bottles, no really "gentle" way i get edge off finger on edge of button, ease rather than press, definitely get the other finger edge onto keyboard. You are looking for 2-3mm depression, NO other note in play, if a bass, just that, no chord.

And pull … there's a feel to it. As with clutch on a car you can bend either by pulling harder, or easing fjnger up. The latter minutely.

Dont be scared of it. Ideally embed in a 'blues' tune, or mixolydian (eg in D on a G row). The best notes to bend musically are 7th (C), b9 b5 (Eb Ab if you have these) but as ever with melodeon "whatever works". Attitude is more important than accuracy

[Sebastian]

Yes, but on a normal 'blues harp', blow and draw reeds can only interact as you describe because they share a hole and are not isolated from each other. In contrast, the pull and push reeds in a melodeon chamber are usually isolated from each other by valves and cannot therefore interact. Hence the bending limits that you describe don't apply. I've no experience of bending melodeon reeds, but if they are 'bent' they must be behaving singly, in a similar manner to valved harps (such as the Suzuki MR350v), so that the direction (pull/push) shouldn't matter.

To my knowledge the Suzuki MR350v is "half-valved" but still bends normally.

According to here on harmonicas bending is limited, when there is only one reed involved (only the blow-reed or only the draw-reed). Bending is the process of forcing the reed to vibrate in the frequency of the resonating cavity. As the resonant pitch goes down, the lower (second) reed becomes more active.

In an accordion there is no changing resonating cavity. So it might be interesting to explore more thoroughly what happens during the bending process on accordions.

[Steve_freereeder]

Forgive my beginner question, but Can you really break the reeds doing this?

I don't think anyone really knows. What is certain is that after long hard playing some reeds will break, but most will not.  So if you want to try it I don't think you are putting the reeds at significant risk.

I've been mulling this over for a while. Prolonged loud playing at high bellows pressure and high volumes of air passing through the reed chamber means that the reeds are vibrating at excessive amplitude for much of the time, which may lead to fatigue cracks and eventual failure. Also, it is often noticed that reeds played loudly will undergo a temporary pitch drop, especially the lower, larger reeds.

This bending notes business as described is different. Although the bellows pressure may be high, the technique of just opening the pallet a tiny amount means that the volume of air and hence the overall air flow rate coming into the reed chamber is relatively small. It is this overall air flow rate which, I think, determines the amplitude of the reed tongue. So bending the pitch of the notes in this way does not excessively increase the reed tongue amplitude, and thus, is probably not injurious to the reed.

So, why does the pitch bending occur?  I believe it is due primarily to the small pallet opening significantly altering the resonant frequency of the reed chamber/reed tongue coupling. You can obtain the same sort of effect by blowing a clarinet mouthpiece on its own, i.e. removed from the rest of the instrument. Blowing the mouthpiece like this produces a squawk-like sound, very unstable in pitch because it is a very short tube removed from the resonant coupling of the rest of the clarinet. However, with a bit of mouth control, it is possible to blow a note of fairly steady pitch. Now, whilst doing this, gradually close the palm of your hand over the end of the mouthpiece tube - the pitch falls dramatically as the tube is nearly closed, as does the volume (controlled by the reed amplitude), until the note is suddenly cut off as the tube is closed completely.

OK - this is all just my speculation; I've not tried to give any numerical physics or acoustics to back it up (anyone want to try, or shoot this idea down?), but I nevertheless have a strong feeling that is what's going on. And once again, I don't think there is any danger to the reed tongues by trying this out.

[Sage Herb]

Yes, but on a normal 'blues harp', blow and draw reeds can only interact as you describe because they share a hole and are not isolated from each other. In contrast, the pull and push reeds in a melodeon chamber are usually isolated from each other by valves and cannot therefore interact. Hence the bending limits that you describe don't apply. I've no experience of bending melodeon reeds, but if they are 'bent' they must be behaving singly, in a similar manner to valved harps (such as the Suzuki MR350v), so that the direction (pull/push) shouldn't matter.

To my knowledge the Suzuki MR350v is "half-valved" but still bends normally.

According to here on harmonicas bending is limited, when there is only one reed involved (only the blow-reed or only the draw-reed). Bending is the process of forcing the reed to vibrate in the frequency of the resonating cavity. As the resonant pitch goes down, the lower (second) reed becomes more active.

In an accordion there is no changing resonating cavity. So it might be interesting to explore more thoroughly what happens during the bending process on accordions.

Yes, but on a normal 'blues harp', blow and draw reeds can only interact as you describe because they share a hole and are not isolated from each other. In contrast, the pull and push reeds in a melodeon chamber are usually isolated from each other by valves and cannot therefore interact. Hence the bending limits that you describe don't apply. I've no experience of bending melodeon reeds, but if they are 'bent' they must be behaving singly, in a similar manner to valved harps (such as the Suzuki MR350v), so that the direction (pull/push) shouldn't matter.

To my knowledge the Suzuki MR350v is "half-valved" but still bends normally.

According to here on harmonicas bending is limited, when there is only one reed involved (only the blow-reed or only the draw-reed). Bending is the process of forcing the reed to vibrate in the frequency of the resonating cavity. As the resonant pitch goes down, the lower (second) reed becomes more active.

In an accordion there is no changing resonating cavity. So it might be interesting to explore more thoroughly what happens during the bending process on accordions.

My original reference to MR350v was too compressed. So, to be accurate, a half-valved harmonica such as the Suzuki MR350v only bends 'normally' in the sense that it behaves like an unvalved harp in respect of holes 1-6 draw and 7-10 blow. In respect of holes 1-6 blow and 7-10 draw bending is possible that is not possible on an unvalved harp. This 'abnormal' bending is made possible by the isolating effect of the valves located on reeds 1-6 of the bottom plate and reeds 7-10 of the top plate. Hence my point that these latter type of bends do not (cannot) rely on interaction between the two reeds in a hole, because there is no such interaction. In relation to melodeons, I was suggesting that similar isolation will occur wherever reeds are valved, which is normally most of them. Hence, logically (though I have no experience of bending melodeon reeds) any bending of melodeon reeds will be non-interactive. I agree of course that harmonica bending of all kinds is facilitated by the player's ability to vary the size and shape of his/her oral cavity, for which there is no similar ability with a melodeon.
Cheers
Steve

[Sebastian]

In respect of holes 1-6 blow and 7-10 draw bending is possible that is not possible on an unvalved harp. This 'abnormal' bending is made possible by the isolating effect of the valves located on reeds 1-6 of the bottom plate and reeds 7-10 of the top plate. Hence my point that these latter type of bends do not (cannot) rely on interaction between the two reeds in a hole, because there is no such interaction. In relation to melodeons, I was suggesting that similar isolation will occur wherever reeds are valved, which is normally most of them. Hence, logically (though I have no experience of bending melodeon reeds) any bending of melodeon reeds will be non-interactive.

What you say sounds convincing. But it contradicts some other information. For example: It's normally sayed, that normal chromatic harmonicas are almost unbendable, because they are valved. That’s why I would like to see some more thorough information, some studies on what does really happen when you bend notes on the accordion. Maybe one could persuade the people in Zwota to repeat their harmonica bending studies with regard to the accordion. :)

[Sage Herb]

In respect of holes 1-6 blow and 7-10 draw bending is possible that is not possible on an unvalved harp. This 'abnormal' bending is made possible by the isolating effect of the valves located on reeds 1-6 of the bottom plate and reeds 7-10 of the top plate. Hence my point that these latter type of bends do not (cannot) rely on interaction between the two reeds in a hole, because there is no such interaction. In relation to melodeons, I was suggesting that similar isolation will occur wherever reeds are valved, which is normally most of them. Hence, logically (though I have no experience of bending melodeon reeds) any bending of melodeon reeds will be non-interactive.

What you say sounds convincing. But it contradicts some other information. For example: It's normally sayed, that normal chromatic harmonicas are almost unbendable, because they are valved. That’s why I would like to see some more thorough information, some studies on what does really happen when you bend notes on the accordion.

Hi Sebastian,
It's simply not true (though, as you say, often claimed) that chromatic harmonicas are unbendable. Try one, especially a blow bend, though all holes will both blow and draw bend a semitone or so. Of course (unlike the Suzukis we were discussing earlier) virtually every reed on a chrom is valved, so the bends will be single reed bends, not interactive ones. I'm absolutely in agreement that ideally someone should be researching accordion bends rather than (as we are) just extrapolating from harmonica behaviour.
Cheers
Steve

[Graham Collicutt]

A thought as to why it might work. When teaching harmonica bends they advise tilting back the hamonica to change the direction of air flow. When melodeon palette is nearly closed all the air flow will be from one end, instead of from all sides when fully open.

I can't do it.

Graham

[Chris Ryall]

We are at risk of one of our occasional tumbles into sophistry here.

Yet again … no experimental evidence that I've seen. Needs a glass walled reed chamber, instrumented pressure/volume, FFT and ideally some strobe cine of what the reed actually does. I personally believe there  might also be some "jet of air" dynamics in this, though the harmonica model would suggest otherwise?

Surely melnet has some bright young people with recent degrees in accoustic engineering who might have the necessary skills?

[Chris Ryall]

Chris do you see any evidence of pitch dropping under pressure on the notes you can bend?   I'm not taking about big changes here, maybe just a dip of 5 or 10 cents?

It's raining in Flanders and Gooik mud is legendary. Found iStrobosoft which does all this. And some tome …

1. All the L range Binci reeds on the van der Aa (including push ones) bend to some extent

2. Yes, a drop of 6-10 cents on high pressure. The big droppers are more bendable to my ear

3. On "throttle and haul" method as described above, I can bend notes up to 45 cents. Is that half a semitone? Here in Belgium it's 100 cents to the € i suspect I could bend slightly more, but don't want to be chucked out of this nice, warm, DRY, internet enabled B&B.

Frans vd Aa is here incidentally, says goed dag to all. Should I ask him for my money back?

[Chris Ryall]

Had a go on the M (non tremelo) bank on my G row. Interestingly C is (again) the best bender. Yes it moves about 6 cents down on pressure. [ignore initial post data, seems I was on A ]

"Throttle and haul" was really interesting! I get a nice bend, comes up at about 44 cents on the FFT. There is a (more) noticable tone change on the M reed, and yes it sounds not unlike Steve doing a good bend on mouth organ.

The A reed will actually bend further, with more tone distortion, but the FFT shows a quantum jump to G# at that point. Displays as a true G# give or take 1-3 cents. Needs more experiment, more kit (though I'm not doing badly from a horse farm in South Brabant)?  Where's that iPhone … think that does spectrums (coffee, am a bit hung over) …

[edit] feeling better hydrated. It looks that these tablet tuners are set up to grab to the nearest concert note as a reference, everything is relative! I think when i pulled A hard it dropped to >50 cents down and the software adjusted. Ignore any speculation previously about quantum leaps, was artefact.

The plotted real time spectrum was useful. High harmonics fade a bit. 2,3,4 definitely come up, to about the strength of the fundamental. They remain narrow bands (though that could be an FFT effect?). It looks that the whole frequency set moves down as a block. But I need an app that displays in true frequencies rather than "relative to a concert note". This is an excellent cure for hangover, incidentally ….

Whoops, 3 posts in a row (better form at 0s & Xs than melnet)? Will shut up and let others try.