arzajac
1521 posts
Nov 28, 2014
6:13 PM
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Harp tweaking/optimizing or customizing is not voodoo or some mystical art. It involves making changes to the instrument to make it play better or make it better suited for an individual.
The process involves the methodology of taking a measurement, making a change and then taking another measurement to assess the progress. You want to measure how close you are to your goal before and after every change.
Gapping is a great example of the process of measuring, making a change and then measuring again.
Here are a few other interventions that follow the same methodology:
Here's a video demonstrating some of the things that are straightforward to quantify so that you can make changes that have a measurable benefit.
Some of these things include:
Tuning: It's easy to measure the pitch of a reed and whether it's in tune with another reed. Play all the octaves available and listen for "beating".
Bending: Bend the 3 draw (or any other bend) with as little force as you possibly can. You will find a "blind spot" somewhere in the middle where the workload is handed off from the draw reed to the blow reed as you bend down. How much work is needed to "skip over" this blind spot can be felt, albeit subjectively; it tends to be more work on lower key harps. We learn to "skip over" this blind spot early on when we are learning to bend. A well-playing harp can be played with very little breath force without having to work hard around the "blind spot".
Reed shape efficiency: By playing a single reed using your lips on the plate off the comb, you can get sensory feedback on how easily the note responds, how much flow you need to make the note sound strong, and how loud the note is. A well-shaped reed will make the whole reed plate vibrate when you play it.
Reed shape efficiency (again): By bending the single reed's note down, you can determine if the reed is prone to squealing. That's a great indicator of how efficiently the reed is set up.
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Custom overblow harps. Harmonica service and repair.
Last Edited by arzajac on Nov 28, 2014 6:14 PM
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9000
205 posts
Nov 28, 2014
6:36 PM
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Thanks for everything that you share here! Really appreciate your experience, expertise and willingness to share. I need to get back on your waiting list...I love the last harps that you repaired/improved!
Jay
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Music speaks where words fail.
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JustFuya
656 posts
Nov 29, 2014
11:36 AM
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Nice video. Thanks.
I wondered about that rivet end gap. Got used to correcting it on Hohners and now I have 2 Suzukis where the reed is buried at that end. I have a feeling that the correction will move the 'hinge point' and effect tuning but we'll see.
EDIT: Actually the Manji reeds are pretty straight right from the pad. It's only the short reed Hammond that buried some reeds at the pad end.
Last Edited by JustFuya on Nov 29, 2014 1:50 PM
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tookatooka
3713 posts
Nov 29, 2014
1:05 PM
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Any chance of describing what you did when you were altering the shape of the reed? Your hand was hiding the bit where the plate was on the piece of wood and you were stroking the reed. Were you trying to straighten it or put a curve on it? It wasn't clear. Many thanks.
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ridge
569 posts
Nov 29, 2014
1:24 PM
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Oh no, Andrew. You are giving away the SECRETS they don't want us to know! I hope you haven't put yourself in too much danger.
Have you ever noticed that after shaping the reed that one side of the reed looks like it closes perfectly and then looking from the other side (by other side I mean rotate the plate 180 degrees) it closes differently? I find that to be the case A LOT when I'm doing this work.
@Tooka - He's trying to get the rivet end of the reed to sit somewhat lower than the rest of the reed. Towards the end of the video he has an annotation about it looking like the reed is in the slot towards the back. That dip gets the rest of the reed set up in a way that helps maximize the amount of the reed that vibrates. Then it's up to you to shape the reed further.
I'd encourage you to buy Richard Sleigh's Hot Rod Harmonicas which demonstrates this very well. For basically the cost of a harmonica ($49) it is well worth it. It's helped me immensely improve my own reed work and has surely paid for itself.
I appreciate what you're doing Andrew. I really like the squeal measurement trick. This harmonica nerd thanks you.
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Ridge's YouTube
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arzajac
1522 posts
Nov 29, 2014
2:42 PM
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Thanks everyone!
JustFuya: It's not all about the rivet end, but it's as important as the rest and shouldn't be ignored. I added a text bubble comment to the video and it may not come up all the time. The reed doesn't go below the slot. It just looks that way because my camera is all-or-nothing below a certain light level. The part where it's closest to the slot just looks dark.
The change in shape should not affect tuning. If the reed is more efficient, it won't vibrate any faster or slower (frequency). But because you are altering how air flows, you may get more amplitude for the amount of force you are exerting. So you may get more volume (decibels) for less work.
I do notice that some re-shaping of the reed can work-harden the reed and lower the pitch. I try to avoid that.
There's one maneuver in particular that you see a lot on YouTube, where you slide a shim all the way to the back of the reed to change the curve at the rivet end. I can instantly hear the pitch drop significantly. I worry about reed life after something like that.
"Plink, plink", *slide*, "plunk, plunk!"
tookatooka: Use pressure/counterpressure to change the shape of the reed. Every reed is (mostly) different. I would do you a disservice to say there is a recipe to follow.
The stroking I was doing involved applying pressure but also being sensitive to the sensory feedback. There is an inflection point towards the rivet end where resistance to downward pressure suddenly drops. You can snap a reed if you just apply pressure in one blow. So I do careful strokes, each time a little further or a little harder. I'm just being careful.
Ridge: Secrets? No secrets here. And anyway, doing the work is hard enough that I doubt there will be a sudden drop in the need for custom harps or harmonica service.
"Have you ever noticed that after shaping the reed that one side of the reed looks like it closes perfectly and then looking from the other side (by other side I mean rotate the plate 180 degrees) it closes differently?"
There's a reason for that... Maybe in another video...
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Custom overblow harps. Harmonica service and repair.
Last Edited by arzajac on Nov 29, 2014 4:54 PM
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tookatooka
3714 posts
Nov 29, 2014
2:58 PM
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Thanks Arzajac.
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ridge
570 posts
Nov 29, 2014
4:30 PM
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My comment about secrets was tongue in cheek :)
The only thing I can think of is the plate is uneven or the reed is twisted or embossing on the edge of the slot. Those are my three theories. Look forward to your take on that.
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Ridge's YouTube
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JustFuya
657 posts
Nov 29, 2014
5:35 PM
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@arzajak - I also appreciate your interpretation of the physical dynamics study. Understanding the science has improved both my tweaking and my playing.
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