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Best of Harp-L Archives

I've started going through HarpL to find some interesting threads.

This is the first one.

OVERBLOWS

What is OverBlowing and How do you do it.

You can bend all the overblows and even the overdraws! I would start with hole six OB which can be generaly bent up to the same note as blow seven (and on some harmonicas, well above.) The trick is to... how do I explain this? isolate the feeling of the tension in your umbasure, so that you can feel the pressure in your mouth required to push the note up... It's clear that an overblow requires a certain kind of air pressure (Yes, somewhat like a blow bend,) the same is true of all the "micro-tones" in the OB bend. Each little shift in pitch requires the same tighting of your air flow... As you get more comfortable you will find that it becomes more natural..

It is even possible to start on the 'Up-Bended" OB and then slide down, this simulates a normal bend, and is useful for intergrating the OB/OD s with the rest of the bends in the instrument. Good luck, I find that the OB bends to me equal in beauty and tonal effect to the other bends in the instrument, and give you the capibility to effect more "horn" like tonalities from the harmonica..

More Discussion on Overblowing

---I just started wondering about overblows. . . . Problem is, I
---don't even know exactly what I'm aiming for . . . .

You are aiming for an entirely new note, with a pitch higher than either of the two reeds in the hole being played. It is usually slightly less than one semitone above the higher-tuned reed, but may be "lipped" up to a true semi- tone. For example, on hole 4 of a C diatonic, blow is C, draw is D, and the overblow is D#, or in other words, E flat.

---. . . . At the very least, how
---different does hole-2 overblow sound from hole-2 blow/bend???

Hole 2 is not often overblown, for two reasons: The wide pitch difference between the blow and draw reeds (minor third) makes it slightly more difficult. And the resulting note (e.g. G# on a C diatonic) is more readily gotten by drawing on hole 3 and bending that note down three semitones. The most common overblows played are those producing notes that otherwise don't exist on an unvalved diatonic. On a major-tuned diatonic, these are in holes 1, 4, 5 and 6. Likewise, overdraws on holes 7, 9 and 10 give new notes (an overdraw is produced by drawing). Holes 4-6 are good ones to try first when learning to overblow.

You're probably aware of the "bending rule" for diatonic harps:

When a blow reed and a draw reed in the same airway are tuned to different notes and are not blocked by windsaving valves, The higher- pitched note can be "bent" down (to any pitch between the original one and one just less than a semitone above the lower note). The lower- pitched note resists being bent at all.

The "hole-2 blow/bend" you mention is an example of the second type, a note that can't be bent much at all.

There is an extension to this rule:

The lower-pitched note in such an airway can be "overblown" or "overdrawn" (to a pitch approximately one semitone above the higher note). The higher-pitched note resists being overblown/overdrawn.

So whether you blow or draw to get a bend or to get an overblow/draw depends on which reed in the hole is tuned lower.

---I once blew
---REALLY hard into hole-3, and got a loud and strange honk (and made my
---eyeballs bulge), but in general blowing super hard into my L.O. just makes
---shrill dog-whistle noises and gives me migraines.
---As I understand it, though, overblows shouldn't require much brute force, if
---any? Or do they?? I know that blow/bends only require the little change
---from "Ooooo" to "Eeeeeee", and no extra force at all. Upper hole draw/bends
---are much harder (for me) to control, but they don't take any force either....

Congratulations on your first overblow. I hope your second is less hazardous to your health. Yes, sheer force can get you an overblow, but played right, an overblow needs only the slightest increase in air pressure, about the same amount as is needed for a bend. Yes, both bends and overblows do require slightly more pressure than a note played straight, but so little more that it can go unnoticed by an experienced player.

This increased pressure is documented by Robert Johnston in a now-famous article in the journal Acustica Australia. He also makes very clear the interesting and related physics behind bending and overblowing.

The important point is that reeds can make noise when blown from the "wrong" direction -- a blow reed can sound when drawn and a draw reed when blown. When they do so, they are called "opening" reeds because the airflow first causes them to move further from the reed plate and open up the hole even wider. For an opening reed to play, the initial air pressure must be slightly greater than for a closing reed. So usually, the necessary pressure escapes through the closing reed before the opening reed can start vibrating.

If you doubt me, and I wouldn't blame you, try the following experiment. Remove the top cover plate from a diatonic harmonica, any brand, any key. Lay your thumb over some of the exposed blow reeds, say holes 4-6. Now BLOW into one of those holes. Voila! Your second overblow. And produced entirely by the DRAW reed! Now with blow holes still blocked, try to bend hole 4 or 6 by drawing into it. If you can bend these notes, it will feel much different than usual. This is the type of bend a chromatic player gets, and it involves only one reed, in this case the draw reed acting as a closing reed. The usual diatonic bend will not happen, because it depends on a second reed acting as an opening reed.

Now it is clear what you need to do to bend and overblow with your harmonica reassembled. In some way or another, you need to raise the air pressure in the harmonica hole just enought to let the second reed function as an opening reed. Yes, one way is by brute-force, eyeball-popping blowing, in which case you provide air faster than it can escape through the slots in the reedplate. An overblow produced in this way is actually a two-note chord, since the closing reed continues to make noise. This is useful, but so is a "clean" overblow since it gives you notes not otherwise available on that harp.

Fortunately, you can also raise the air pressure that little bit needed for opening-reed playing by airway geometry (mouth and throat shape) alone. Some airway geometries are better, some worse, for the playing of reeds in their normal (i.e. "closing") mode. To either bend or overblow, you want to find a geometry that is TERRIBLE for normal, closing reeds. If you can reduce that reed's vibration, the pressure will push it close to (or into) the slot in the reedplate. In effect, the reed becomes its own (imperfect) windsaver valve. Once that slot is blocked, the airway pressure rises and the second reed can begin to play. Of course it is playing in the "wrong" direction, as an opening reed, but that is what you want.

But if the underlying physics of bends and overblows are so related, why are they so different? I'd be happy to address this another time.

---Or should I just leave the beach in disgrace, go home and kick a chair, then
---shell out the bucks for some commercial "In Just SEVEN DAYS, YOU TOO Can
---OVERBLOW" thingy?

In just seven minutes, you can remove a coverplate and produce wonderful overblows. To do it with the coverplates on, I'd give yourself about seven months to get it down. Ask questions like those you just did, and it may indeed take you only seven days.

Overblow Notes

All bends go down and all overblows go up ( that sounds logical )

On a C harp you get the following overblows:

hole 1: (c) D#
hole 2: (e) G#
hole 3: (g) C (B#)
hole 4: (c) D#
hole 5: (e) F#
hole 6: (g) A#

And overdraws on the following:
hole 7: (c) C#
hole 8: (e) F (E#)
hole 9: (g) G#
hole 10: (c) C#

More Discussion

--- why can't I get an overblow?! I'm watching the Howard Levy video and he says
--- to use the same method as blow bending. I CAN'T DO IT!
--- someone please help me.

three things:

1. Yes, I agree that the way you hold your mouth to the harmonica, your embouchure, that is, the way you shape the tongue and interior of your vocal tract, and how you direct the air at the hole in order to overblow is pretty close to the way you would do for blow bending.

2. How the reeds are set up [gapped] can greatly facilitate overblowing.

3. And there are tricks to help you get there sooner.

As for #1, learning to blow bend should help you to understand how to shape your mouth, tongue, etc., for overblowing... they are similar. For me it feels as if I concentrate the air flow more off the roof of my mouth and more downward rather than straight into the harp.

Regarding #2, it can be generally said that the blow reed must be gapped closer than the draw reed to help with overblowing. That is, it is closer to being level with the slot it sits over than the draw reed is to its slot, but not so low as to make it hard to sound the blow reed in it's usual blow manner. This adjustment can be tricky, but trying to get my draw reeds to be able to bend fluidly and completely led me to find an easy way to set the gap for overblowing as well.

For #3, try this. Remove the covers from the harp. Place transparent tape over just the blow reed slot, then draw and adjust the gap on the draw reed until it's to your liking for ease of bending. Remove the tape, and try both reeds... the blow reed may be right as is. But if you can close down the blow reed, little by little, until the gap is as small as you can get it while still being able to play the blow note [i.e., it doesn't choke off,] then it will also become easier to overblow, too. In order to do this while the reedplate is on the harp, I usually use a paperclip that's straightened out with a kink in the straight end to be able to reach in the hole and "gradually" bit by bit press the reed toward the hole. You can also press it all the way to flat with the slot, and then, bit by bit push the reed back out of the slot until the desired gap is achieved.

BTW, I take exception with the suggestion made the other day to press the reed either in toward the slot or out away from it by pushing on it near the root of the reed. I find there is greater potential to badly bend the reed along a rather sharp line. Nor do I try to bend the longer reeds by pushing on the end of the reed, as it is easy to slip off and really bend or damage the reed trying to get the tool out after it slips. So, instead I prefer to press the reed about a 1/4" away from the root end to allow the springiness of the reed itself to cause the bend to occur less abruptly or also suddenly. Bending out such a kink can be difficult and may cause the reed to go out of tune suddenly as well. This method of bending therefore helps one adjust the reed in very small increments. Once the reed is in what seems a desired gap, draw or blow [whichever] on it while gently plucking the reed. This seems to help settle the reed into a responsive vibrating pattern. Over even a few minutes, though, the reed may revert somewhat back to an undesirable position, as a normal condition of stressing the metal into position. But the adjustment is at least closer to true now...just rebend it a little more until it settles into the gap you want.

Oh, and I guess, for a #4, I have to believe yes, you CAN DO IT!! Try manipulating your embouchure and air flow while using small amounts of pressure... you don't have to blow hard to get bends and overbends...and in fact, using softer breath will let you hold notes longer when trying to "get it right" and allow you to concentrate closely to the subtle nuances you'll need to find to develop such techniques.

Another Viewpoint

As an aid to overblows, I might suggest starting by playing the draw note, which gets the draw reed activated (the draw reed is the one that is the overblow reed), then immediately blowing in the hole, as Larry is suggesting, using a blowbend type of action. I've found this helpful with some players. On a poorly-adjusted harp, with bad compression, I always find OBs easier to approach in this way. Many find that hole 6 or 5 is easiest to start.

This is for holes 1-6. Overdrawing 7-10, would call for the opposite approach, sounding the blow reed first, and then immediately hitting the draw, with some mouth shape similar to a draw bend. If you are having difficulty with overblowing, you might still try overdrawing, as some players hit their first overbend in that way.

I think it helps to know the pitch of the note that you are looking for (1/2 step higher than the highest pitched note in the hole). That way you will recognize the correct sound of an overbend when you hear it. Also, the OBs tend to work better for many players when the shape of the mouth is resonant to that note. Some teachers suggest having the mouth shaped to whistle the exact pitch of the OB (the octave is important).

One thing to listen for, it is very common that you will hear something of a pre-cursor to the OB, which is a ratty sounding honk. This is a combination of the lower pitched reed sounding its fixed pitch and the higher pitched reed sounding the OB pitch. If you hear this, you are moving in the right direction. Just work to refine and clean it up.

Once you get them, you can work to tune the OBs (they generally sound in flat) but bending them up. Yes, they move up in bending. This is very important if you wish to use them in performance, as is all bending intonation.

I should mention that I'm no OB expert. I think a great help might be if there is an online audio example of the various OB pitches and pre-cursor sounds available. Other than that, maybe someone can recommend an instructional product that has audio helps.

If any of this is confusing or unclear, any number of OB adepts on the list could maybe help you further. I'd also be happy to clarify my own remarks.

A quick note on gapping

The standard litany on gapping is to "start" at the point where the gap is the same width as the reed you are attempting to gap. From there you experiment according to your own needs. Specifically you will want to gap it to avoid the point where the reed seizes up. It's all very personal, but you "will" find your own comfort zone in the gapping with further experimentation.