Philosofy
428 posts
Dec 12, 2012
7:24 PM
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I saw a video where Dave Barret was talking about bending, and it involves tuning the pitch of your mouth to the pitch of the note you are trying to achieve. That got me thinking: if I have an A harp, and perform a 3 draw two step bend, and I remove the harp without moving my mouth at all, and replace it with a C harp, will I still be doing a two step bend, or will it be off?
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Blueharper
204 posts
Dec 12, 2012
8:11 PM
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Maybe some more experienced guys could answer,but I would say that differing keys take a different embouchure.Or at least a different tongue shape.
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Afro Blue
20 posts
Dec 12, 2012
8:13 PM
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The embouchure is different for both of those delicate holes. I doubt it would be the same, besides, the lowest a 3-hole draw goes is a step and a half. You're going to need to learn to bend properly on both harmonicas respectively.
I think what Barret is hinting as is the fact that you can bend the 2-hole draw down too far and make it sound flat like James Cotton does in his famous youtube video "Slow Blues." You have to listen for the pitch and humming is a good method for determining pitch just as tapping your foot is a good way to learn how to stay on beat. Since you have 3 (or four if you count Adam's Blue Third) notes on the 3-hole draw, you need to hear the one you're going for in order to go for it accurately.
The way I learned the 3 hole Whole Step Bend was from Kim Wilson's version of Got My Mojo Working with Jimmy Rogers and Adam's version of St. Louis Blues which feature a 3-hole draw whole step bend which is singled out and easily heard.
I'm sorry if you know all this already and was just asking a general question. That's my two cents. Ignore it if it doesn't apply to you. :) Good chattin' Philosofy.
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Hunger is the best spice.
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The Iceman
544 posts
Dec 13, 2012
3:23 PM
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Been teaching diatonic for 15 years or so and do not buy into the "tuning your mouth to the pitch of the note" explanation, although it is important to have a solid mental inner ear perception of the note.
I have found that the bend is created by redirecting airflow (in or out) over a "hump" created by your tongue, anywhere from way back in the throat to right up behind your front teeth (for exhale high end bends).
Placement of this "hump" does change slightly depending on which note you are trying to create.
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The Iceman
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Greg Heumann
1887 posts
Dec 13, 2012
6:00 PM
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I tend to agree more with Iceman than my friend Dave here. I believe that a bend is induced by introducing aerodynamic turbulence that changes the angle of the airflow through the comb, and therefore begins the dual reed interaction. Iceman's description certainly better matches what I feel - however I also agree that the amount required differs per harp.
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/Greg
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SuperBee
705 posts
Dec 13, 2012
6:15 PM
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Well yeah, when David goes into explaining techniques and exercises he is all about the position and movement of the tongue hump. This is actually what I understand him to mean by tuning your mouth to the pitch of the bend. Practically it's the same thing. I think.
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Frank
1571 posts
Dec 13, 2012
6:22 PM
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He's identifying a concept > (tuning the pitch of your mouth to the pitch of the note) Dave has been teaching harmonica Professionally since he was a skinny, long haired pimply surfer dude , he also teaches the factors that the movement (humping) of the tongue etc. provide in the execution of bending reeds. Lets get real here boys and girls!
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HarpNinja
2983 posts
Dec 13, 2012
6:45 PM
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I agree with Ice. You can set up the action of a harp so it hits the sweet spot consistently between keys.
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Custom Harmonicas
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STME58
325 posts
Dec 13, 2012
11:34 PM
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Greg mentioned aerodynamic turbulence and that got me thinking, the opposite of turbulent flow is laminar flow and a good way to achieve laminar flow in a small wind tunnel is to bundle standard drinking straws together and have the air pass though the bundle on its way to the object under test.
I did some experimenting with a C Blues Harp that I can overblow on holes 4, 5 and 6.
What I did was take a drinking straw and place it on the holes, one at a time, and blow through it. I found that when I did this I got the overblow note on hole 4 and 5 but not on 6.
If I blew very gently though the straw into hole 4 I got a slightly sharp B according to the tuner, but the slightest additional pressure and it would pop up to a very flat E. Playing it this way felt very much like getting the low soft tone on a bawu that pops up in pitch when you blow a little harder. Hole 4 blow played normally was right on C.
Hole 5 was right on E played normally. With light pressure though the star it was a little flat. A bit more pressure and it would jump up to a slightly sharp F#.
Hole 6 played normally was a slightly sharp G. Though the straw lightly it was right on G and as I blew harder it flattened but never popped up to an overblow like holes 4 and 5 did.
When I drew on hole 4 though the straw, I got a C#, not the expected D. If I attempted the bend the note through the straw, instead of going down, it climbed up to D. I was surprised I could get any action at all attempting to bend through the straw.
When I drew on hole 5 normally I got a slightly sharp F. Drawing though the straw I got a very flat F. If I tried to bend the note down as I would in normal playing it would up come to an on pitch F.
Draw 6 played normally was right on A. Though the straw it was a little sharp. Through the straw, I could bend it down with regular bending technique to just below G#.
I am sure I am not the first to try this. Has anyone else done this? Has anyone seen any research on this phenomenon?
The only concrete takeaway I get from this data is I need to tune my C harp.
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harpdude61
1603 posts
Dec 14, 2012
4:59 AM
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I'm sure there are many techniques that make bending possible. I prefer the reshaping of the throat method because of the control achieved.
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SuperBee
717 posts
Dec 14, 2012
5:34 AM
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as we say in Australia "whatever yer reckon"
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Frank
1576 posts
Dec 14, 2012
5:31 AM
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Here is how I learned bending...I'll mostly use the thumbs and the knuckles of the index fingers - it has it's advantages :)
Last Edited by on Dec 14, 2012 5:42 AM
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harpwrench
626 posts
Dec 14, 2012
6:15 AM
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If you want some cheap entertainment- play a note, pull the harp away without changing mouth shape etc
Then tap your cheek with your fingers, there should be a sweet spot that makes an identifiable pitch. Compare the pitch to notes you play. Play with this and pay attention to what's happening, report back whether or not you believe the mouth is being tuned to the pitch (or an overtone or different octave).
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Custom Harmonicas
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HarpNinja
2986 posts
Dec 14, 2012
6:33 AM
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@harpwrench
I don't have a harp but I just tried this and clearly jaw position effected pitch. As I wiggled my tongue, though, the effect wasn't very profound (or noticeable?).
Yesterday, before posting here, I played the same riff 2" 3 3' 3" on a G (Crossover) harp and then an Eb (Manji)...both gapped to my taste. I must have gone back and forth a dozen times and would swear that there was next to know measurable change in my jaw and tongue position, yet I was able to bend the notes the same.
I am sure, over time, my body has adjusted to playing different keys, and I know that I have to vary technique based on what I am playing, but for how I bend - which is like what Ice describes, it is very very consistent regardless of key.
Is it possible that those bending from a TB embochure or with a different breathing style, etc. end up doing this differently. Unfortunately, I can only explicitly feel this from my own perspective and I probably can't avoid compensating in ways that are beyond habit for me.
When TB'ing, I feel like my jaw and tongue and breathing are very different from harp to harp, but I've associated that with not being as proficient as some others.
Based on feedback from customers, my own experience, and hounding others, I do think there is a "sweet spot" in a harp's action where you feel say a 3' bend is going to lock in with same attack from key to key.
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Custom Harmonicas
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harpwrench
627 posts
Dec 14, 2012
7:50 AM
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Harpninja- it might be that when you move your jaw, it's changing something else that's actually changing the pitch. I was just watching my throat in the mirror with a flashlight. Seems to me we have some control over the tongue, but the throat is mostly on auto-pilot. There's a lot going on in there and it seems pretty unlikely you can change one thing without something else changing too.
Let's think about it-
Fact- sound waves travel from the reed into your mouth.
Fact- The wave at some point is reflected back to the reed.
Read it on the internet so it must be true- the energy in that sound wave reinforces oscillation.
Watching my throat, I observed change in size as well as moving forward/backward.
Fact- Moving the point of reflection forward or back changes the timing of this sound wave relative to where the reed is in its oscillation cycle.
I suspect- this plays a part in what's happening with bends.
Interesting discussion. Someone more educated than me please take it from here, I'm just a mechanic not a scientist!
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Custom Harmonicas
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The Iceman
547 posts
Dec 14, 2012
7:54 AM
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My conclusions over the years, in my quest to find the minimal amount of movement needed to achieve the maximum effect, is that it is that "hump" in the tongue that controls bending.
Opening the throat is good for deepening the tone.
Most seem to "bundle" stuff - in other words, they may focus on their throat and feel that is where the control is. However, internal awareness has shown that, even though they may focus on the throat, they still engage the tongue in the proper fashion to create the notes through bending technique.
My focus has been on learning how to "unbundle" all these movements and find the ONE that has the true control.
Same with getting harmonica players to relax their necks and shoulders while playing, as neck/shoulder muscle tension does not directly effect the outcome, even though many have "bundled" this as well as they evolved.
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The Iceman
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HarpNinja
2987 posts
Dec 14, 2012
8:58 AM
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Great follow up posts above!
The hardest part about this is making sure, when we are just using written communication, is having the same understanding.
For example, what Ice says about the tongue makes total sense to me, yet I've read other people's posts suggesting this isn't the case - although it seems to me they are saying the same thing.
I've tried in the past to "bend from the throat", and have always observed that the most moving part in a deep TB end like that is my tongue.
Then, when trying harpwrench's experiment, I was surprised that it was my jaw position and not tongue effecting pitch.
Then, I started wondering if in my experiment last night I was moving something in the way back of my throat moving from Eb to G harps to hit the bends.
I love this stuff...the science part. STME is a great resource here, and I enjoy reading his comments.
One thing I started doing after chatting with him via email (and STME, I apologize for not already emailing you this) is using new (to me) measurement tools when evaluating the audio qualities of a harp, and not just using my ears.
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Custom Harmonicas
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HarpNinja
2988 posts
Dec 14, 2012
9:04 AM
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I already caught myself drifting from the OP....the original question is brilliant and, as we've found, hard to answer.
It got me thinking about how amazing the human body is...IME, there HAS to be some physical difference in playing the same thing on different keyed harps - now exactly what is what we are trying to naild down here, and as I think through this more and more, I realize how many damn variables there are to consider - and we can just do it without thinking.
I never go from a LF to a high F and think, "Ok, now I have to adjust x, y, and z". I just play it. Granted, 99.9% of us end up drifting in and out of tune on bends anyways, but it becomes pretty automatic.
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Custom Harmonicas
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harpwrench
628 posts
Dec 14, 2012
9:41 AM
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I'm not disagreeing with Iceman about arching the tongue, I just don't agree redirection of airflow explains all that's going on and perhaps has nothing to do with what's actually causing a bend.
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Custom Harmonicas
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The Iceman
548 posts
Dec 14, 2012
5:55 PM
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harpwrench...what do you feel causes the reed to bend?
All I know is that, when I teach absolute beginners diatonic harmonica technique and walk them through the arching of the tongue towards different target spots on the roof of their mouths, every one of them bends TO EXACT PITCH within two weeks, even three hole inhale.
It's kinda amazing and I wish I had someone show me this when I started out, as it took a lot of years to fumble towards controlling the bends.
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The Iceman
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harpwrench
630 posts
Dec 14, 2012
6:54 PM
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Like I said, I'm not disagreeing with tongue arching being a great way to cause the bend. I just have trouble believing it's because of airflow manipulation. I think it could be sound wave reflection and the timing of that wave energy returning to the oscillator. Engineer needed for cleanup!
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Custom Harmonicas
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STME58
330 posts
Dec 15, 2012
12:32 AM
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I like what Iceman said about "bundling". This is a massively multivariable phenomenon. I doubt any of us can change just one thing at a time. The thing we are trying to change may not be the significant factor at all, but rather one of the unintended changes that comes along with it that is giving us the result we see.
I don't really know what causes a bend. I might hypothesize that it is the reed responding to how turbulent the air flow is. Bringing the tongue up to the roof of the mouth and making the chamber narrower would tend to smooth out the airflow and make it less turbulent. I don’t know how to test this hypothesis, perhaps miniature cameras and smoke generators inside the mouth? ? The idea of changing the mouth shape to create a resonant cavity that matches the desired pitch makes sense too. I did see a paper someone on this forum pointed me to comparing the oral cavity and comb slot to a Helmholtz resonator (a spherical bottle with a long thin neck for which the resonant frequency can be easily calculated). It could be both of these or neither.
I still struggle to get bends on pitch, although it gets better as I work with a tuner in front of me. Because of the invisible nature of this problem I expect that each individual using trial and error, along with some suggestions from a teacher with a lot of experience, is going to be the way it is learned. It is low tech biofeedback. When you do the right thing, you get the pitch you want, even if you don’t know what the “right thing” you are doing is, you learn to repeat it and get the notes you want. I saw an example of high tech biofeedback in cycling. It turns out that a lot of riders inadvertently start pushing down on the pedals before they reach top dead center, and use some of their power pushing in the wrong direction. Of course they can’t tell they are doing this. By instrumenting the cranks and displaying a red light when this happens and a green light when the rider is in sync, the rider learns to pedal correctly. At least with the harp it is obvious when you are not getting the right tone. Of course it is possible that, like the cyclist, a harpist could get an adequate result, but be working much harder than necessary due to poor technique.
I would like to understand the physics, but it is not necessary to learning to play. Conversely, knowing how the physics works is unlikely to have any positive effect on my playing. Knowing the physics would put me in a position to design a better instrument, or a better process to make a consistent instrument, but won’t do much for my ability to play well.
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Komuso
129 posts
Dec 15, 2012
1:43 AM
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There's a few papers around on the physics of Harmonica
Pitch Control In Harmonica Playing
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Paul Cohen aka Komuso Tokugawa
HarpNinja - Your harmonica Mojo Dojo
Bringing the Boogie to the Bitstream
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Philosofy
430 posts
Dec 15, 2012
8:36 AM
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Here's my thoughts:
We know that bending involves interaction of the vibrations from both the blow and draw reeds. My first thought was that it was air direction which causes it, but I threw that theory out, because you bend the same way if the harp is upside down.
Then, along comes the Dave Barret comment that got me thinking. That made me think that your mouth/tongue/throat is slightly different going from one key harp to another. But I don't think that is the case, either.
My current theory (and I might be wrong, this is just me thinking) is this:
When the reeds vibrate, they produce a sound wave that travels in two direction: out the back of the harp, and back through the slot into your mouth. When playing a straight note, there is no reflection of the sound wave back into the harp, or, in other words, no resonance. But when you bend, you reflect some of the sound wave back into the harp, which affects the reeds. The more you reflect, the more the bend. It would be like a mirror reflecting a beam of light. Its the placement of the mirror that counts, and the color of the light doesn't have any affect.
I also think that the reflected wave probably has to be out of phase with the original note, and sets up a sympathetic vibration of the blow reed.
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Frank
1587 posts
Dec 15, 2012
8:40 AM
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I appreciate everyone’s well thought out opinions and such, but I still say it's the way you twist the harp that generates the bending of it.
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Afro Blue
37 posts
Dec 15, 2012
8:59 AM
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Try warbling holes 4 and 5 and then bend the warble like in Whammer Jammer, you feel your tongue move as everyone has described.
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Hunger is the best spice.
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STME58
331 posts
Dec 15, 2012
9:04 AM
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@Komuso, thanks for posting the link to the Robert Johnson paper. I had not seen that one. This list of references in the paper contains some interesting titles I will have to look up.
Johnson's experiments and analysis seem to indicate that most of the bending phenomenon can be explained by resonant frequencies that have mostly to do with cavity volume. Turbulent or laminar airflow is not even considered and yet he gets some pretty good mathematical agreement with his experiments. This seems to somewhat support Philosofy’s ideas on the subject, although a bit more complex. I would contend that the resonance is always there, resonance is fundamental to musical instruments. (Also, the color of light can affect how it bends. This is why a prism works. :-))
@Frank, your model of bending is much easier to analyze. I have a model of a Golden Melody in CAD. If I get a chance I will run it though a Finite Element Analysis with a torque applied to it and post the results. My FEA program makes gif files of things bending back and forth. I have posted some before of reeds vibrating. They might look good as one of you message headers.
Last Edited by on Dec 15, 2012 9:05 AM
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Pistolcat
343 posts
Dec 15, 2012
2:47 PM
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I'm sorry, I got into this pretty late and haven't scrutinized all of the posts above. I believe and feel that i "tune" my mouth to the note I am bending for. I can't say exactly how I do this BUT: I can draw a steady two hole draw and move my tongue all around in my mouth without getting any noticeable bending. I also believe I use almost same "technique" for whistling out, in, draw-bending harp, blow-bending harp and overbending. The difference is just in the sweetspot.
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Pistolkatt - Pistolkatts youtube
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STME58
332 posts
Dec 15, 2012
11:15 PM
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“I would tend to think that turbulent/laminar flow won't apply here.”
The Johnson paper certainly seems to support this.
I also saw in the paper near the bottom of page two, an observation that the amplitude of vibration of the typically non sounding reed is largest when the note is bent the lowest. This agrees with the comments I have seen several times on this forum that bending a note “to the floor” is hard on the reeds. As explained here it would be the 8 draw reed that you would damage by bending the 8 blow all the way down.
Last Edited by on Dec 15, 2012 11:15 PM
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roadharp
97 posts
Dec 16, 2012
10:38 AM
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Man I am simple but what about articulation e o ew aw that's what Jerry portnoy teaches. Drop your jaw while doing it.hope it helps it helped me.
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roadharp
98 posts
Dec 16, 2012
10:49 AM
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My bad e ew o aw sorry guys.
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roadharp
99 posts
Dec 16, 2012
11:37 AM
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Really Frank I can use it man ha ha.
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The Iceman
555 posts
Dec 16, 2012
12:58 PM
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@STME58
Bending a note "to the floor" is not what is hard on the reed. It is pressing it "to the floor" hard or trying to go through the floor that does the damage.
Most don't have the subtle awareness of where that floor is, hence, they slam it.
If you can find/feel that floor and float your note about 1 foot above it, you will find that the note you've created is right on pitch. That foot below it is the wiggle room of almost 1/4 tone below the note.
Use it wisely.
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The Iceman
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