Explained below. There are some cool harps that make an appearance in this video, including a possible Confederate harmonica - I know I say there were virtually no harmonicas in the Civil War, but this one MIGHT have been one of the few - plus a demonstration of a very early chord harmonica.
Every time I see the two sides harps I think there ought to be a way to interlace the reeds to make them smaller. The trick would be to isolate the two sides inside that smaller harp. I think you'd have to run thin partitions between each cell in the area between the reed plates and covers. That gets me wondering what that would do to the tone. Have you ever seen a harp that partitions the cells between the reed plates and covers?
Is there even a word for the cavity between the reed plate and the cover? I keep referring to that space and I don't know the word!
It would make a difference. It would be louder, it would have some of the effect that a double thick reedplate has in some ways. It would drastically change air flow. Think about the difference between a special 20 and Marine Band. Comparing the two, it would make a special 20 sound like a Marine Band in comparison. Am I making sense? I'm trying to say it would be the antithesis of a side vent harp in tone. You can try it using a temporary barrier. I'd say to actually build this harp for real would be mucho dinero. ---------- David Elk River Harmonicas
Maybe I'll get some balsa wood and see if I can't make a mock up with a hot glue gun and an exacto knife. I think ideally, something like that would be metal and you'd fine machine parts, weld them to the cover and have them slide into groves on the reed plate like Hohner Puck cover slides on (only sideways). If someone had a setup for injection molding, or even better yet, one of those Makerbots 3D printers a plastic cover might work, especially if it made the harp louder, since plastic covers tend to make harps too quiet to start.
I think you should try brass. You only need to do one reed, then compare tone with the reeds next to it. Think J.B. Weld. ---------- David Elk River Harmonicas
I might actually have some J.B. Weld around. I could probably cut a piece out of an old reed plate that would fit. I've got my busted L.O. parts that I put through the dryer. It looks like there is enough brass between the last hole and the screw holes to make a divider. I don't have a really good tool for cutting brass. Hmm, probably should do top and bottom, with a divider on either side of the hole (I could get away with two dividers by doing the end... wait a second...)
Okay, so after first giving it a try with pieces of a business card cut to have a little tab I could insert into the adjacent slot holes (too flimsy) and then stepping up to clay dividers (not an idea reflecting surface, but a nice snug fit for purposes of isolating the chamber (both top and bottom) I can say that the results are inconclusive! There seems to be a slight change in tone, but it's well within the subjective range. Science! It was you suggesting isolating just one hole that got me going. I always make projects bigger in my head than they need to be. It does seem to make it a little more airtight. (The clay is is actually holding the harp together instead of screws!) It still bends okay. I can't overblow with enough consistency to see if it effects that.
I think, if you had a injection molded or printed cover that had grooves on it would be pretty easy to isolate the two halves of a double sided harp with the reeds interlaced. With reeds packed that tight the reed plate might be kind of fragile on account of all the missing metal, but it seems you could make a regular sized double sided harp. Of course, injection molding or printing would mean some sort of plastic unless you wanted to do it all in metal with cut pieces. I can't think of a way to make it quality and cheap. It's too bad. It would be sort of neat to make double sided harps fit in a regular case (without going down to a Puck!) It would be sort of neat to buy a F Major/F Minor harp in one, or to only have to carry 6 harps to be able to play anything in 2nd position. (I was thinking they could use something like that piece of brass in that one old Hohner harp that lined the inside of the holes. I thought if you had a piece of metal like that and then welded a thin slice of metal along the front/back/top/bottom edges you could get it rigid enough to mount a reed plate too, although you'd have to get creative with the how to mount it. No place for screws! They seem to already have the cover issues covered (vent holes on top instead of the back). I think I need to spend some time figuring out CAD. Maybe I could get the parts I need 3D printed if I already had the CAD measurements figured out.
Now I think I'm going to go brush my teeth. I think I may have ingested some clay. :)
You should try making it so air only comes up from the bottom to simulate the dividers going up to the coverplate and forming a seal there. That's where I think you'll see more of a change in tone. Keep air from coming in from the sides at all. Or maybe you already did that. You can cut the brass with a hammer and a chisel, if you have nothing else. It'll bend it all to heck, but you could hammer it back out. ---------- David Elk River Harmonicas
