tookatooka
2381 posts
Jul 20, 2011
12:56 PM
|
Just a thought. The chambers in the comb where the reeds vibrate are usually a few millimetres longer than necessary. I was wondering whether anyone has tried experimenting with reducing the length by adding a little bit of something like (blue tack) to see what would happen.
I don't know if the length of the chamber is a tuned length or just a length that manufacturers use to ensure the reeds swing freely.
Anyone been down this road? If so is there any point in trying it out.
Maybe a concave surface at the end of the chamber would make the air flow in a way that would improve the reeds performance?
Just throwing it out for discussion if you are inclined and curious.
----------
|
dukeofwail
23 posts
Jul 20, 2011
2:15 PM
|
Those are good questions. I bet others will pitch in on this one. Meantime, you SHOULD try it, and add to our shared pool of knowledge.
What harps are you contemplating using?
----------
Robert Hale
Learn Harmonica via Webcam
Low Rates, High Results
Gilbert AZ (Phoenix)
http://www.dukeofwail.com
|
nacoran
4339 posts
Jul 20, 2011
9:37 PM
|
I hadn't thought of making the end concave, but I've wondered if there was a way to may a discrete comb narrower by angling the divider to take advantage of the fact that the reed doesn't swing at the anchor end. I was also wondering about a curved divider to angle the air down onto the tip of the reed, but since I'm only marginally handy it's just been a thought experiment.
----------
Nate
Facebook
Thread Organizer (A list of all sorts of useful threads)
|
Jehosaphat
86 posts
Jul 20, 2011
10:14 PM
|
Well for what its worth i have personally always lightly embossed the ends of the slots,it just seemed to me to make sense in that you emboss to make the tolerances tighter so why not include the gap at the end?
|
MrVerylongusername
1760 posts
Jul 21, 2011
2:00 AM
|
@Tooka
The curved ends idea sounds interesting. Reminds me of "Tate Ramps" and the ridges in Dick Sjoeberg's combs.
|
HarpNinja
1520 posts
Jul 21, 2011
7:06 AM
|
IME, those who mod combs tend to find ways to extend those slots and not narrow them.
----------
Mike
Quicksilver Custom Harmonicas
|
Oso
47 posts
Jul 21, 2011
7:06 AM
|
I have been doing all of these things mentioned above as experiments. I have been making my own combs for a while now and I been experimenting.
Things I have done:
shortening air chambers
lengthening air chambers
beveling the air chambers on both sides
thicker combs
thinner combs
using screws that go all the way thru the comb and reed plates
using screws that only go thru one side of reed plate (use twice the amout of screws?)
combs out os SS
combs from brass
combs from aluminum
combs from all types of woods
Now I am making combs out of exotic woods
Last Edited by on Jul 21, 2011 7:10 AM
|
nacoran
4340 posts
Jul 21, 2011
7:49 AM
|
My other big crazy idea is turning the reeds 90 degrees along the long axis. You'd use accordion reed plates instead of harp reed plates (since accordions already have single reed reed plates.) Each reed would pair with the reeds to their right and to their left, possibly giving you the option for deep draws and overblows on one very narrow harp. I figured 12 reeds, 4 1/2 steps apart gives you:
1 (the first reed)
44 (each 4 notes for the next 11)
and maybe a couple notes below and above, but at least 45 half steps, so more than your 3 octaves.
Of course, chords would be crazy to do and it wouldn't be Richter, but it would be really compact, using 12 reeds to cover nearly 4 octaves.
----------
Nate
Facebook
Thread Organizer (A list of all sorts of useful threads)
|
genesis
91 posts
Jul 21, 2011
9:29 AM
|
Keeping the slots lengths very short improves response a good deal.
|
MrVerylongusername
1766 posts
Jul 21, 2011
9:52 AM
|
@Nate,
I don't think that would work unless the blow holes alternated from front to back (not very practical). Maybe I'm visualising it wrong?
@Genesis
So in an ideal world there would be an optimum comb for each key, as opposed to the one size fits all approach?
|
nacoran
4345 posts
Jul 21, 2011
1:06 PM
|
MVLUN- yeah, the reeds would alternate blow and draw. The way I'm picturing it it would be just like a normal hole, just turned 90 degrees. What would make it different is each reed would be part of two holes. I still haven't worked out the sound would get out, short of drilling holes in the far side of the comb or slapping regular covers on them, which would defeat the narrowness advantages. And with holes in the end of each chamber... I don't know. I keep looking for a broken accordion to play with, but it seems even broken accordions are expensive.
And to your response to Randy, I'm guessing a an optimum thickness too. I've wondered, again with accordion parts, if you could make a harp with a series of reed plates staggered like steps on a comb cut like the piece of wood under stairs, only with a much shallower cut. The end result would be the comb would be much narrower on the top end. I imagine it would leak air pretty badly though.
I suppose you could cut the reed plate holes at a slight angle and flatten a spot for the rivet and accomplish the same thing, but more like a ramp with bumps, since the reed plate would still be one piece.
That would mean cutting reed slots in reed plates at an angle though, and not the easy way, actually a cut that would make the edge of the reed slots sharper. Hmm, maybe it's time to bust out the MS Paint for some crazy drawings.
I also tried to figure out a system to 'cheat' on a chromatic. The idea was just to take advantage of the fact that a chromatic has all the reeds, but make it 'simple' like a diatonic. To do that I had a crazy scheme- replace the slide with a metal punch card, sort of like the old paper programming cards for computers. You'd slide the punch card in where the slide would normally go and by virtue of which holes were punched on the card it would let you play in a key. To switch keys you'd just swap out the cards. You'd have to start on a different hole for different keys, but you wouldn't have to worry about sharps or flats or anything like that. Unfortunately, since the idea was to keep it simple, it had to preserve the blow/draw pattern and I it seems you'd need at least 3 harps to be able to play all the keys, plus the punch cards. Since chromatics are so much more expensive than comparable diatonics the idea just wasn't practical. Now, a punch card system might still be full. You could use it to turn a chromatic into different some different diatonic tunings, and if you made perforated cards (maybe plastic would be cheaper than metal?) you could make a really simple system for people to cheaply play with different tunings without having to have the courage to retune their reeds.
-And my harmonica ideas aren't nearly as crazy as my other invention ideas, so I should probably shut up know before they come to take me away- hee hee
----------
Nate
Facebook
Thread Organizer (A list of all sorts of useful threads)
|
