SpecialSean
24 posts
Oct 06, 2014
6:10 PM
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I'm not very good at customizing them so what do you think the answer is? I also don't have the money to pay anyone.
Thanks in advance!
Sean
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The Iceman
2192 posts
Oct 06, 2014
6:22 PM
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I've always liked Golden Melody and also admit to not trying out all the new harmonicas out there.
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The Iceman
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arzajac
1489 posts
Oct 06, 2014
7:37 PM
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It's a crapshoot. Out-of-the-box is hit and miss. You have better odds with higher keys for overblows and lower keys for the overdraws. The 6 OB is pretty reliable all around.
Long-slot is better. Hohner reeds become short-slot in keys higher than C. Manji and Seydel reeds are long-slot in all keys. But an out-of-the-box GM is more airtight than an out-of-the-box Manji.
If there was one harp that had reliable Obs out-of-the-box, it would sell like hotcakes. There just is no such thing.
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Custom overblow harps. Harmonica service and repair.
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bluemoose
1005 posts
Oct 06, 2014
9:04 PM
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CrossOvers come pretty close. Then get Andrew (Arzajac) to massage them.
MBH Webbrain - a GUI guide to Adam's Youtube vids
FerretCat Webbrain - Jason Ricci's vids (by hair colour!)
Last Edited by bluemoose on Oct 06, 2014 9:06 PM
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boris_plotnikov
1014 posts
Oct 07, 2014
12:42 AM
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It's a lottery. Sometimes you can get all overblows using stock Seydel Session steel/1847/Soloist Pro or Hohner Golden Melody/Special 20/MB Deluxe/Crossover or Suzuki Manji/Olive/Fabulous, sometimes not. Same model and manufacturer, but absolutely no overblows.
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Excuse my bad English.
My videos.
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The Iceman
2196 posts
Oct 07, 2014
11:50 AM
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OB
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The Iceman
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harpwrench
921 posts
Oct 07, 2014
12:15 PM
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Old wives tale IMO
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www.spiersharmonicas.com
High performance harmonicas.
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The Iceman
2198 posts
Oct 07, 2014
12:38 PM
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Lee Oskars use shorter/ wider slots. This is why they squeel when OB.
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The Iceman
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Martin
704 posts
Oct 07, 2014
12:50 PM
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My all time best OB harp was an LO in Eb. And I mean that it was just perfect -- but a bit of an anomaly
I can´t set up a harmonica for the life of me so I tend to cling to GM or S20´s for the generally best results.
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harpwrench
922 posts
Oct 07, 2014
1:05 PM
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My son's Vette kicks my Volkswagen's ass. His car has red paint, mine is black. So red cars are faster than black cars.
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www.spiersharmonicas.com
High performance harmonicas.
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SuperBee
2215 posts
Oct 07, 2014
1:14 PM
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On Sunday I did a little work on a G Crossover. Just some very light sanding on the comb, and much more sanding of the draw plate. The draw plate quickly demonstrated that the area around the 6 and 7 slots was rather leaky. Also the area around 9-10 slots and the rivet end of the 1 slot, but the 6/7 area took a lot more sanding to get to.
I've wondered how much of a difference this process really makes...When I put the harp back together, not only did it now easily overblow on 6 but also for the first time ever I could overdraw 7. And 10. And 9. And overblow 4 and 5 once I paid more attention to gaps.
My point being, I am not highly skilled in the technique of playing overblow/draw, nor in customising. If you can't pay someone to do the work, the choice is probably to learn to do a little work or keep buying harps and hope you get lucky. The optimistic approach could get fairly expensive. For the price of a single harp (or less) you could equip for work and invest some time in watching some video and start driving yourself crazy trying to perfect your harps...
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harpdude61
2185 posts
Oct 07, 2014
1:22 PM
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I get much better overblow results with my Golden Melodys with no squeal. The L.O.s and Suzukis that I have, simply gapped, overblowed okay, but I too had squeal issues.
My opinion doesn't carry much weight but the thinner slot/reed works best for me.
Also...recently bought a new GM in "A" and "F". The "F" OBed fine on 4,5, and needed a little gapping on 6......The "A" would not overblow any. The gaps were HUGE when I opened up the harp.
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arzajac
1490 posts
Oct 07, 2014
1:41 PM
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Keeping things in context...
With some work, any harp can play overblows amazingly well. "Short-slot" harps can play overblows just like long-slot ones. Remember, the archetypal custom harp is a Marine Band, which is short-slot starting in the key of Dd and above. A few of my favourite OB harps are short slot Suzuki harps with about an hour's work on them.
But the question is about out-of-the-box harps without any work. Not even a few minutes of simple work like SuperBee describes.
It's a gamble. What will increase the odds in your favour? You have a better chance of getting an overblow out of a factory harp if it is long slot rather than short-slot.
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Custom overblow harps. Harmonica service and repair.
Last Edited by arzajac on Oct 07, 2014 1:45 PM
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STME58
1126 posts
Oct 07, 2014
2:05 PM
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If someone can give me the dimensions of a short and long slot reed in the same pitch, I can model them and see it anything shows up that might explain a difference. Perhaps something like the frequency of the bending mode and the torsional mode are closer together on one than the other.
There is a lot more to this than the reed by itself so I don't expect anything conclusive out of studying the reed, but it might provide some pieces to the puzzle.
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arzajac
1491 posts
Oct 07, 2014
3:18 PM
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"Why is that "
Let's back it up a little bit and start with whether short-slot harps have a lower incidence of being able to play overblows out of the box than long slot. There is no evidence such as a randomized, double-blind study of a few thousand out-of-the-box harps to say conclusively what the percentages are. I am basing my statement on observation. If you have observed the opposite, then that's interesting.
If you have conclusive evidence about factory harps and overblows, if someone has studied it, please let me know.
...Back to your question...
I think it's due to the fact that longer reeds have a better profile (as in curve, not mensur) more often. Is this due to how the harps are manufactured or assembled, I don't know.
I also think that a long slot can tolerate a larger airleak than a short slot and no factory harp is perfectly airtight.
Shorter reeds are also more prone to squeal, which doesn't help.
STME58 - I agree, that would add something. I do think that it would be hard to determine how to model the flow of air through the slot, though.
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Custom overblow harps. Harmonica service and repair.
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harpdude61
2186 posts
Oct 07, 2014
3:37 PM
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If the thickness is the same..wouldn't a longer narrow reed be more flexible than a shorter wider reed?? Excited to learn something new from this thread!
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STME58
1127 posts
Oct 07, 2014
4:28 PM
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harpdude, The width of the reed does not affect the frequency. but the thickness and length do so you are part right. For a given pitch of reed, there are many solutions of thickness and length. If you want a shorter reed you will need to make it thinner to keep the frequency the same.
The basic equation for a spring mass system is;
freq = Squareroot(spring rate/mass)
The reed is both the spring and the mass. The part that bends a lot, near the root is mostly spring, and the part near the end that barely bends is mostly mass. When you lengthen the reed you increases the mass so you need to make it thicker to increase the spring rate and keep the frequency the same. Of course when you make it thicker you also increase the mass so it gets complex. If you double the thickness the spring rate goes up by a factor of 8 but the mass only doubles.
The reason width doesn't not effect frequency is if I double the width, I double the spring rate, and I double the mass. The ratio of spring rate to mass does not change.
Think of this equation as it relates to tuning. Spring rate is in the numerator so if I lower it I lower the pitch. To lower the spring rate I remove materiel near the root. Mass is in the denominator so if I reduce mass, pitch goes up. To reduce mass I remove material from the tip.
Last Edited by STME58 on Oct 07, 2014 4:28 PM
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harpdude61
2187 posts
Oct 07, 2014
4:49 PM
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Thanks STME58..but all I was wondering is would a longer/narrow reed be easier to overblow or even bend in general....but if the longer reed must be thicker then the flexibility of the two are close to the same?
The physics and ergonomics of the harmonica is interesting to me. Such as...what is optimal reed dimensions(LxWxH), best metal, hole size, hole shape,comb thickness, etc. Is a reed optimal if the thickness stays the same throughout it's length? or would a tapered reed work better?
I really thought after the B-Rad fiasco that someone would really dig into this stuff.
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JustFuya
595 posts
Oct 07, 2014
10:13 PM
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How about a triangular slot with a corresponding triangular reed.
Just tossing that out there. It seems there have been no major innovative harp breakthroughs in many years. No doubt there were some very intelligent, clever and hard working people who accomplished a high degree of accuracy using slide rules and drafting boards. But here we are today.
@STME - I appreciate the value of building a harp library of solid models and envision substantial if not radical design ideas while the harp industry continues to struggle with the manufacture of a consistent product. I volunteer any non-destructive measurements you desire of the CO's and GM's that I own (+/-.002).
I also have a set of Manji plates in the key of A with draw 5 broken @ 1/3 from rivet. These are available for destructive testing (thickness +/-.0002).
Curious: can you model the properties of a perfect alloy for reed flex and durability.
Last Edited by JustFuya on Oct 08, 2014 10:32 AM
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STME58
1128 posts
Oct 07, 2014
10:39 PM
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JustFuya,
Do you have a long and a short slot harp that have the same note reed in them? If so, I would love to get the dimensions to do a comparison between long and short at the same pitch.
By triangular, do you mean like this Bawu reed?
These have been made for centuries. Attached to a pipe with holes in it like a flute it will sound at the resonant frequency of the pipe as fingered. It would not be too hard to proto this using a metal cutting laser to produce sets of reed plates. The kerf of the laser might be to big and give you a leaky reed though. I suspect the Bawu reeds are sheared though I have never seen one made.
I don't think it would be too hard to produce a consistent overblowing harmonica if you had even half the resources a typical high tech consumer product uses in development, 20 engineers for a year and a 10 million dollar tooling budget. Then if you could sell a 100,000 harps a month at $100 each you could recover you investment and make a profit in a year or so. anyone think you could convince an investor you could sell 100,000 harps a month for a couple of years? I have no idea what the harp market is but I expect it is much smaller than that.
Found these tidbits about the market:
Honer in Strategy and Business
I see here that in 2006 Hohner had 85% of the market but it does not say how big the market is.
in 1969 1.8 million harmonicas were sold at $1.50 (about $10 today adjusted for inflation) to 750,000 US players.
But no current data on market size.
Funny thing about materials, as far a flex or in engineering terms the Modulus of Elasticity changes very little with alloy. Steels are different from brass or aluminum but within a material it doesn't change much. That is why it is fairly easy to calculate the resonant frequency of a reed from measurements and be very close to the actual value. Durability, or fatigue life, is something else and depends not only on the exact alloy but how the part was made and heat treated.
Last Edited by STME58 on Oct 07, 2014 11:30 PM
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JustFuya
597 posts
Oct 08, 2014
1:35 PM
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I was hoping my Manji reed slots were short but that is not the case. In fact all the Manji dimensions that I measured were nearly identical to the Hohner. That backs up the point in my previous post where I facetiously mentioned the triangular shaped reed. Everyone has been making the same basic instrument for a very long time. The only variances on the 'basic' harp that I have noted during my limited exposure are in quality, material and assembly methods with one exception: That OB harp with all the finger holes in the plastic covers. Somebody out there is at least trying.
@STME - That's where I think your solid models might come in. It's much easier and cheaper to 'what if' on a computer than in real life with hard tooling and prototypes.
Anyway, I measured 2 slots and 1 reed width on 3 instruments:
Mfgr -- Key -- 1B L X W -- 10B L X W -- Reed W
Hohnr -- C -- .657 X .080 -- .344 X .075 -- .074
Hohnr -- A -- .657 X .082 -- .344 X .075 -- .079
Manji -- A -- .654 X .081 -- .345 X .072 -- .079
Incidently the distance between the slots was identical for all.
@arzajak - 'mensur'? I had to look that one up and I seriously love it. I'm going to try to use it twice in a sentence today so I'll have it forever but that's going to be tough one. Very nice fit tho. Kudos.
Last Edited by JustFuya on Oct 09, 2014 8:09 PM
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STME58
1130 posts
Oct 08, 2014
8:38 PM
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JustFuya,
Models can help understand things and my reduce the number of prototypes needed but they are not yet to the point where they replace prototypes. One thing that is very important in a reed model that is missing in your date is the transition from the rivet plate to the reed. Also if the reed tapers in any way this need to be put into the model. Here is a sample reed print with the data that would be critical to the model.
Reed Print
If the edges are not near sharp I would need to know the radii also. I accidentally left the width of the reed off. THat is not a critical until you go to analyze twisting mode vibration but it is needed.
Last Edited by STME58 on Oct 08, 2014 8:42 PM
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JustFuya
598 posts
Oct 08, 2014
10:31 PM
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@STME: I understand. I've spent almost this entire day researching and contemplating manufacturing methods using fairly current technology to test your cost figures. I started out by thinning out the start up crew (think tank) to 3 and roughly estimating the elapsed time from the initial meeting to first delivery at 9 months. I was doing OK until I got to the reeds. The material and methods have really bogged me down and I am now imagining angry investors. But it's been a great learning exercise and I'm having fun writing the narrative.
One of the things I did was compare the Manji profile to Hohner's. (mensur not curve.) The Hohner reeds have a rougher surface finish and the transitions at the pads and tips are curved. Manji reeds have a fine finish and angled transitions (roughly 45 degrees).
I will be happy to provide more info but the short vs long reed debate is moot until I can get my hands on a short reed plate.
The transition angle will be fairly accurate but since the radius is a bit larger than the step I'll have to give you my best eyeball estimate. It will still be fairly close. I will draw the profile in 2-D CAD and adjust the radius until it is proportionate to the real thing.
::Regarding the Bawu reed, I think I would do it with a one hit "lance & form" punch. The gap would be minimal.
With the laser you will have a .003 or more gap all around and might create extra cleanup work. Most importantly, laser cuts require a lead-in cut so it can heat up the material and get some momentum going. The entry point is usually ugly and is generally located outside the part perimeter or inside cutouts.
Last Edited by JustFuya on Oct 08, 2014 11:02 PM
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STME58
1131 posts
Oct 08, 2014
11:10 PM
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JustFuya, the cost I put forward was not an estimate of what it would cost to develop an overblow harp but just taking what several projects I have worked on cost and cutting it in half! When you are pretty certain you can sell 300k to 500k per month of something at a reasonable profit you can afford to spend a bit developing it.
Sounds like you are really getting into this. I suspect you are right about the manufacturing method for the Bawu. It sounds like you have some sheet metal experience. Have you looked into coining as a method of producing reeds? I think the tooling costs are too high for the size of the market but it would give you a very consistent reed that is more fatigue resistant than a milled one.
If you get me dimension of reeds I will make solid models and look at frequencies and mode shapes.
What is really needed here it to combine the Finite Element Analysis (FEA) I am doing with computational fluid dynamics (CFD) and study a pair of reeds in its slot attached to a resonating chamber and air source (oral cavity and lungs. A model like this might give insights into what is going on beyond the experiment that are in the literature. But without a lot of verification it would not be too trustworthy.
I could not find a meaning for mensur that fit this topic. I only found it as the name of Germanic fencing practice, typically done in academic fraternities, in with the object is to scar your opponents face. I just finished reading a book in which I learned that Rudolph Diels, the first head of the Gestapo, had scars he got in college from this practice but I don't recall the term mensur being used. What do you and arzajak mean by the term?
Last Edited by STME58 on Oct 08, 2014 11:14 PM
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arzajac
1492 posts
Oct 09, 2014
4:32 AM
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In this article, Winslow Yerxa explains what Steve Baker means by the term "mensur"
Starting in 2005, Hohner has made changes to the reeds used in their chromatics, and this has occasioned some concern in the player community. As long as I'm writing about Hohner chromatics, I decided to seek some information on this. I got some historical perspective from Rick Epping, former US product manager and designer of the XB-40 diatonic, and additional information from Steve Baker, who was able to relay information from Hohner Germany.
To start, I should explain the German word Mensur as explained by Steve Baker: “Hohner uses this term to refer to the physical dimensions of the reed—length and width. With any given Mensur you can make the reed sound at different pitches through the type of profile milled into the upper edge of the reed, i.e. the variation in thickness throughout the length.”
When Rick Epping was designing the XB-40, which is about the same size as a 10-hole chromatic, he relates, “I chose the Knittlinger Mensur used for the Auto Valve for the XB-40 reeds, which differed from the Chromatic Mensur in that the narrow, 1.9mm reeds began at a longer length than they did on the Chromatic Mensur, and had a better response than high reeds that were 2.1mm wide. This Mensur was subsequently adopted for the chromatics for the same reason.”
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Custom overblow harps. Harmonica service and repair.
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nacoran
8046 posts
Oct 09, 2014
1:40 PM
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I once wrote an inquiry to the people who make the liquid metals used in high end golf clubs. Unfortunately, they didn't see enough margin on selling reeds (and they have a proprietary process so if they don't make it no one will). The interesting thing about the liquid metals is they are supposed to be less brittle because of the molecular alignment, thanks to a special cooling process.
There have been, historically, plastic reeds. (You can buy a Magnus online for about $10, pretty in a 50's sort of way, but they aren't great harps.) I imagine laminates wouldn't fare particularly well since the vibration and torque would seem to work against the joint. Steel and titanium don't worry as long as they don't go past a certain degree of deflection. Knowing that, I'd really like to know if you could adjust a harp to keep it below that degree of deflection (without compromising volume too much). (Maybe magnets on the tips could be magnetically opposed to magnets on the covers- sort of a built in compression?
Unfortunately, I just stopped taking math too early in my schooling. I always thought it would be cool to lay out some other instruments in a Richter tuning with a harmonica mouthpiece. 'Harmonica' ocarinas and pan flutes, etc, but the reed is such a clever little valve.
A whistle uses a little ball to essentially do the same job as a reed, interrupting the flow of air, except it's vibration is more erratic. Made from good materials it shouldn't wear out though. Would there be a way to control that vibration to get useful notes? A slotted whistle ball, (maybe a magnetic spring?)
I know the ideas are kind of fanciful, but there are working harps out there with magnetic whammy bars, and others with sympathetic reeds, and Justfuya seemed to be calling for a spitballing session. :)
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Nate
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First Post- May 8, 2009
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JustFuya
606 posts
Oct 09, 2014
7:07 PM
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The passion I had yesterday, while confined to a small space, is diminished somewhat with the onset of cooler weather. I did finish the outline and learned quite a bit in the process, but I'm not getting the vibe that there is wide interest in starting up a Hohner competitor. If anyone needs a thesis outline, complete with conclusions, let me know off line.
So getting back on track....
@STME - I am happy to provide the data you seek but I am confused. I misread 'Hohners higher than C' as 'Hohners C and higher'. OK. My bad. So I popped open a Hohner GM F expecting short reeds and they are the same as all the others.
Am I misinterpreting 'higher'? Does anyone know of a Hohner (or other make) and key that uses the short reed style?
Last Edited by JustFuya on Oct 09, 2014 9:19 PM
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nacoran
8047 posts
Oct 09, 2014
9:45 PM
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Let me postulate one more potential form- an extremely rigid reed. So rigid that the goal is for it to not bend. Where the rivet would usually be, instead, you have a small hole. Instead of a rivet you have a magnet on place, in balance with a magnet on the reed. This is your fulcrum. Just beyond that you have another set of magnets. While the fulcrum magnets are about levitation the reed back farther are acting more like magnetic springs. How they are adjusted adjusts the frequency the reed swings at. Tiny screws allow them to be adjusted for distance (under constant force I think a magnet loses something like 5% of it's energy over 50 years or something like that, so you might need to eventually adjust, but no flexing means the reeds don't actually worry or deteriorate.
I have no idea what that does to reed interactions, but I bet I could get a large scale test piece working.
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Nate
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yonderwall
80 posts
Oct 10, 2014
4:50 AM
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They are making a lot of progress in metal 3D printers at this point.
Imagine being able to rapidly print a reed plate that can immediately overblow just the way you want it to. Even if the printers are too expensive for everyone to own, perhaps someone like Andrew or Joe could invest in one and churn out "custom" reed plates with Rockin' Ron's turnaround time :)
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JustFuya
607 posts
Oct 10, 2014
10:09 AM
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Not sure WE are in spitball mode yet. I however did wander off but I'm back on track. As soon as I can find a short reed harp and then supply @STME with the data to draw the model, we are at a standstill.
Update: I ordered the 2 test specimens. Both are Suzuki in the key of D: a Manji & a Hammond Promaster. Suzuki reeds will be easier to measure with higher accuracy than Hohner reeds. And it will less of an apple orange comparison.
Last Edited by JustFuya on Oct 10, 2014 2:39 PM
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nacoran
8049 posts
Oct 10, 2014
5:11 PM
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Hmm, a harmonica/spitball shooter!!!
Yonderwall, I had a debate with the late Chris M. once about how far 3D printing would eventually come. I'm of the opinion that if a human can do it, (i.e. it's actually possible to do) eventually a robot or machine will be able to do it better. I wish I could find the link, but there was a great example of piano pieces composed by computers that should send shivers down every composers spine.
If we can create microchips where the space of a couple atoms is important, assuming money wasn't an issue, we should be able to duplicate a harmonica that has been set up to overblow to play exactly (or at least within any possible humanly perceivable parameter) the same.
Of course, the question comes down to whether the money is there... yet. As prices fall, eventually we'll get there. Of course, at that point it's quite possible that a harmonica might not have any moving parts. Solid state sensors and strong syth abilities- there already is a midi style harp on the market that doubles as a full function synthesizer (although it's actually primarily marketed as an accessibility device for people with paralysis.) I don't think it can perceive and respond to the subtle pressure changes for say, an over blow, but I suspect as sensors get better and cheaper it will.
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Nate
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JustFuya
610 posts
Oct 11, 2014
2:59 PM
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I just visited Pat Misson's site which has a ton of harp info. I was wrong when I said that harp innovation was dead. There are people thinking about improvement all the time and they are receiving patents for their ideas.
Here's an interesting page on Pat's site:
http://www.patmissin.com/ffaq/q35.html
And here is a link from that page to a patent which claims a harp design that will make OBs as easy as simple notes. Totally out of the box thinking:
http://www.google.com/patents/US6359204?dq=6359204
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