I’ve been puzzling, without much success, over what might be the effects of differences in blade sharpness and ramp angle (or ramp bevel angle) on overall timbre and/or on the relationship between the voicing/playability of the lower vs. upper registers.
If anyone has had any consistent experience that a particular variation on one or another of these elements consistently produces a certain kind of result, I would be grateful for that information.
Best wishes,
Jerry
Just buncha hunches here, but documented by a few whistles of widely varied builds.
To me it appears that the sharpness of the blade is related to the material of the blade proper. Softer plastics, and sharper blades give an extremely chiffy high end, and possibly buzz when pushig the low end, finally an ugly transition of this low end when gradually blown in second octave.
The exact same shape in metal may be perfectly effective. However, rigidity of the cutting edge of the blade still seem necessary.
Some rare whistles (Alba Q1) work really well with a perfectly dull blade: it’s not even sharpened at all, just square cut through the thickness of the metal sheet (tube). Of course, the window opening seems to need adjustment to get up in second register.
Related: the buzz one gets from plastic recorders, which are exact geometrical copies of hardwood originals, but these have a much rounder sound. The cure for these plastic recorders is the same as with pennywhistles: blunting the edge with a thin file or sandpaper helps.
Also, it seems to me this applies to the very cutting edge of the blade, where the material is thinned to the point it gets soft. After, the length of the blade seems to be more a question of creating “walls” around it, but the slope itself seems secondary.
I wonder if this could be interpreted by the cutting edge acting as a sort of free-reed.
To illustrate, I can compare a Copeland low D and my Le Coants, with its appparently recorder-like blade. On closer examination, one sees it has a blunted cutting edge, cut at a much steeper angle, making it closer to, say, a Grinter, itself similar to a Susato or Burke composite.
The Copeland (and many others) as you know as no “ramp” to speak of, except by its “ears” (walls) probably giving an equivalent result with the limit layer.
However, the cutting edges of the Copeland, Le Coant are rather similar with a steep angle. Interestingly, the Copeland and Le Coant have pretty similar sound “colours”.
As for cast plastic heads, where the buzz phenomenon seems to appear more frequently, it would be worthwhile checking if a hard coating material could correct it. Anyone ever tried bending a thin metal sheet, to shape it as a wedge, then glue it around the blade and ramp?
Else, would there be chemical coatings (or glues) to harden the blade of the plastic heads?
Dude, you’re asking for all the “secret stuff” - if we told you we’d have to… well, you know. I’m afraid there’s only one way to find out, become a monk of the “Secret Order of the Knights Fipplar” 
OK, Loren.
How much is this going to cost me, and where do I drop the loot?
Best wishes,
Jerry
Oh, now that’s perfect. 
let’s see so the signatures would read something like: “John Doe KTF {Scot.}”
Excellent. I like it.
Should I take Loren’s and McHaffie’s posts to mean they don’t know either? (This could be a poll question.)
C’mon, you guys. Throw me a bone. Bill? Thomas-Hastay? Anybody?
Best wishes,
Jerry
Empirically speaking…
Seems to me that a shallower blade angle (=thinner blade) produces a quieter, less chiffy whistle, and vice versa. The shallow blad also seems to favor easy register changes. With wood, this can be a bit of a problem since a very thin blade is fragile and can warp with breath moisture. Lately, I’ve been coating the top and bottom of my blades with a water-thin cyanoacrylate glue after voicing. Most of it soaks in, effectively turning the wooden blade into a tougher, plastic one.
I don’t make my blades too sharp. Glenn Scultz recommended leaving the thin edge “the thickness of a business card”. Works for me.
Thanks, Paul: both your idea of hardening the blade, and Glen Schultz’s advice may be precious.
However, I wonder if oiling the blade with linseed oil (as recommended by Mollenhauer) which tends to polymerize solid is not a less agressive treatment to the wood. Btw, what you get with cyanoacrilate is not a “plastic” but a composite–there’s fiber in the resin, and it’s a whole difference, structurally.
I should have reminded this link http://chiffboard.mati.ca/viewtopic.php?t=15215 rather than my unclear written explanation on Yvon Le Coant’s characteristical blades.
It starts like a beveled tube (à la Grinter), with a rather steep edge, then a flat recorder-like ramp takes place. It works.
What about marks on the ramp of Sindt whistle? Angled three notches.Products of his milling machine.How is the effect because of these existence? So subtle that we can call it ‘nothing’?
Yep, ‘nothing’ pretty much sums it up! 
Seriously, I make my heads in a very similar fashion, and a few extra passes across the blade ramp with an end mill eliminates the faceted appearance and produces a smooth surface.
There’s absolutely no difference in tone or playability between smooth and faceted blade ramps… trust me on this issue, I’ve done my homework!
Thanks for sharing that! Gary. Now I got my brain much clearer. 
I was voicing several Delrin whistles last night and came up with something very interesting. I had cut the windways and square windows (same operation), and rough fitted fipples and the head ferrules. I had also drilled the fingerholes. I had not yet started filing the blade angle at all (which I do by hand with various files, BTW). On a whim I tried playing the whistles and was surprised that they DID play, even without any ramp at all!! To be sure, the sound was very quiet and impure with lots of extraneous noise, but I was able to easily play two full octaves. I really didn’t expect the whistles to do more than make some airy noises. As I filed the blades closer and closer to their final shape, the sound got louder and clearer.
This might have implications for making a really quiet practice whistle. If we can figure out how to keep the whistle quiet, but get rid of the extra noise, this might be useful.
The Alba Q1 (as in Quiet One) has a blunt plade, no ramp at all, about 1 to 2 mm thick. QED.
I hate to be the one to burst anyone’s bubble, but to be perfectly honest Jerry, I did a lot… and I mean a LOT of just hard work experimenting, and there is a breaking point on just how far you can go one way or the other on how shallow or steep the blade is…
As Paul mentioned that a whistle will sound without even tooling the materials beyond basic openings for airflow.
Once you get to actual tooling though, you’ll find that once you zero in on an angle and “sharpness” of the blade that works best for you and your particular design… fractions of an inch start to make a difference as far as how the whistle reacts accross the octaves, jumps back and forth, performs overall, overall sound (as far as chiff, resonance, etc.) and so on. Sure… it’ll make a noise just about no matter what, but … well there you have it.
So to be honest… I’d go with Paul’s overall observations on blade performance as far as the flatter you go, the more difficult your register changes are and vice versa, and with much ado you can get rid of most of the chiff even on a pretty steep angled blade, just takes some variation in design. Everyone makes their own differently.
And that’s the point… everyone makes 'em a bit different and that’s the way it oughtta be, so that’s my bone to throw!!! I’m sure everyone even has some little something they think may or may not have an ever so slight effect on things that makes all the difference in the world to make their whistles… THEIRS. I know I do, so there’s always gonna be some good stuff out there to figure out!
(Hint, hint: yep, pretty consistent corrolation, but tweak it all around and make us proud!! )
Take care,
John
So what blade shapes apply to what configurations? IOW, I’m thinking that there must be a fairly consistent and reliable way to predict this sort of thing. What with all the WhOA going on, I’m sure a comparative study could be done if it hasn’t been already.
Hi, Nano.
[Mouse]Hi, Nano![/Mouse]
Although there are compounding factors, it would be extremely useful to compile more of the kind of information Zoob (Hey man! congratulations!) [Mouse]Cool, dude! Way to go. Do they have sunflower seeds in France?[/Mouse] has provided about different whistles, their blade configurations and timbre/playing characteristics.
Best wishes,
Jerry
Hi, Jerry.
Hi, Mouse.
What I was thinking was that given a consistent tube diameter and length, there seem to be still a fair variety of head designs. That’s the starting point I would look to. Has this been studied comparatively?
Not as far as I’m aware.
Best wishes,
Jerry
Well, for heaven’s sake. tsk
Hi Jerry,
Over the past 15 years I have used 4 different designs for forming windways/windows, and that’s just in wooden whistles, I haven’t even looked at the die-press/deformed tube methods.
One thing I have noticed us that for my whistles, an optimal ramp angle of about 20 degrees works best, and if I want to produce a clean/pure tone then the blade needs to be sharp, but not to the point where the material loses it’s shape.
When I was setting up for Syn whistles, I tried to examine the blade angle thing more closely (in another place), and while I got some answers which confirmed the 20 degree thing, I got the impression there, and from articles I have read since, that playing with blade angles was “secret recorder makers business” and best left to them.
I think I agree. If your’e on a good thing, stick to it!
syn