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ttonon

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Hi Harpomatic,

 

I guess we have different interpretations on what is meant by very conclusive proof. To me, it would mean a well performed experiment reproducing whatever is claimed. We are at the end of a long, interesting thread, and for simplicity, let me just state that I do accept as fact that both single reed and double reed bends are possible, depending on how the harmonica is blown. The issue I have concerns only the most common draw bend, made on reeds that have a lower pitched reed in the same chamber. When I took the covers off the harmonica, exposing the reed plates, and ddid such a draw bend, I was able to put my finger over and completely block the higher pitched reed slot, thus making it impossible for that reed to participate in the bend. Experimenting in this way, I could discern no difference in musical tone whether or not the lower pitched reed slot was covered. My own experimenting here thus makes this issue puzzling to me.

 

In his above post, Pat Missin may offer a clue to my dilemna when he states: "As the bend deepens, the lower pitched reed starts to vibrate as an opening reed, at a higher frequency than its normal pitch." Thus, in my experimenting, I may not have achieved a deep enough bend for the lower pitched reed to respond. If this is the case, then, perhaps enough mean air flow is necessary to pass through the slot in order to bend (open) the tongue of this reed far enough away from its rest position, for the necesssary vibration. Speculating further, such a high mean flow (or Reynolds Number) may be necessary to produce enough vortex activity to initiate vibration. Such vortex induced vibrations are very common in Nature.

 

Regards,

Tom

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Posted (edited)

Tom, exactly what Pat says - you didn't pull enough air to activate the opposing reed. What you did is a single reeded bend, in both cases, with and without the finger blocking off the opposite reed. In this case, indeed, valves are even helpful, as that single reed will bend even easier. Double reeded bends are a technique that once conquered, seems to be hard to avoid using, it's such a staple of blues playing that one tends to overdo it. However it is not easy to develop this technique at first, and you're simply not doing it right (yet). Its not just the force of the airflow, but a change of direction. I have seen many beginners struggle with it, though to someone who can do it it seems like there's nothing to it. Try it on a 10 hole harp on inhale, hole 3 is the bendiest, due to exactly this phenomenon - the reed opposite to B there is G, so you can bend down potentially to G, but in practice you can easily get A, and even Ab. Thats how those humble diatonics can play all those missing notes. So, unless you are hitting that A, you are not getting the double reeded bend, but once you do - you will hear and feel the difference. It does take the force of breath that's scary to a beginner, for the fear of damaging the reeds... no worries - these are much more resilient than we think.

Ps. About the ability to reproduce the experiment: Pat and I, along with any intermediate level harp player can do it a thousand times out of a thousand tries, it works every time without fail.

Pps. listen to the first 2 notes of this track, the first is the bend taken from the extreme bottom (without releasing it back up), just straight start and finish "at the bent bottom". The second is the transition from the initialy bent note up to its normal pitch. I know that Carlos retuned his harp according to the principle in question, just for that note alone, to be able to bend it further than normal... (if I am not mistaken, the title refers to that fact, retuning of the C note to B for the bend)...

 

https://m.youtube.com/watch?v=E7VWbALgbZA

Edited by harpomatic

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Hi Harpomatic,

 

O Yeah, this guy is really good, and it never ceases to amaze me how musicians are able to find strikingly new ways of playing harmonica and guitar - two musical instruments that are blessed by the fact that they allow such enhanced intimate physical manipulation/interaction of the sound source by the musician.

 

Concerning my own disposition on the occurrence of double reed bends in the harmonica, I cannot assert that my experimentation is at all sufficient, and I must remain open minded. Perhaps, when the pendulum of interest again swings in that direction, I'll revisit the issue with more experimental ambition. Thanks for the updates.

 

Regards,

Tom

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