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How To Build a Cajon - Goals |
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Written by Casey
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Friday, August 14 2009 14:43 |
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Page 2 of 12
In building this cajon, i had hoped to make an instrument that was a little bigger, a little bassier, and generally more burly than the standard cajon. I was worried about passing some point of diminishing return by enlarging the cajon without having adequate knowledge to simultaneously tweak other factors in the design (thickness of the front, shape of the box, size of the hole, etc), but i think it worked very well. The tapa of the cajon presented by Ocaña is about 12.5" by 18". This tapa is about 14" by 21", with the other measurements similarly scaled. This increases the internal volume by a factor of about 1.4 or more, which is no kinda small potatoes.
Another unusual feature of this cajon is that i made a hinged door on the back. To avoid impacting the kick sound too much, i designed it to seal well, and to stay closed with significant force (as opposed to a simple latch.) Since it was the first cajon i made, i knew that i would be inside it a lot, adjusting things, installing new gadgets, etc, so it was worth it to me (even though the door took a large percentage of the total construction time.) The risk is that the bass sound would suffer; instructions i read from Ocaña and others make a big deal about how well the box is sealed, glued, etc, and certainly such a door compromises that issue. My feeling is that my seal is not so great, but the bass sound is very good. I may add a second layer of bicycle rubber to make it a tighter seal, or replace the sealing material altogether, but it already sounds much better than store-bought cajones.
What i would do differently next time:
- Perhaps make the hole a bit smaller (closer to the "normal" size holes on cajones)
- Perhaps not include a door
- I haven't played enough professionally-made cajones to know, but i'd consider making a "regular-sized" cajon instead - there may be a reason they are smaller, but then again, it may just be their traditional place as either solo or ensemble instruments in a particular culture and genre.
- I would consider a solid-wood tapa (see Wood and Frame discussion).
- I would put the hole in the traditional upper-back location, rather than the side (see the section on the hole, below, for more.
- I would use a different snare design (see snare section for ample discussion).
- I would invest in some clamps, for god's sake.
- Just as a note: salvaged and reused materials could easily be used in this project!
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Last Updated on Thursday, April 08 2010 16:01 |
Re: wood, see page 3, called, cleverly, "Wood and Frame": http://caseyconnor.org/jl/cajon?start=2 -- As far as species of wood are concerned, I doubt it makes much difference, since we're talking about laminate plywood here.
Re: Ocana, see the intro page, "Germán Ocaña".
Hi -
For the tapa, see page 3, called, cleverly, "wood and frame": http://caseyconnor.org/jl/cajon?start=2
For the snares, see page 7, called, cleverly, "snares": http://caseyconnor.org/jl/cajon?start=6
Good luck,
-Casey
@Job - see http://caseyconnor.org/jl/cajon?start=3 for info about the hole size issues. The size doesn't seem to matter so much, in my experience. The function of the hole is to "let the bass out", in a simple sense; the cajon "kick" sound is making a "thud" wavefront. Without the hole, the thud hangs out inside the box and doesn't come across as loudly. My personal conviction (as explained at that link) is that the hole isn't part of a "Helmholtz" model, where it "tunes" an air spring, so much as it just prevents the air pressure of the internal space from preventing the tapa from moving and allows the thud wavefront to escape. If the tapa vibrated like a traditional drum head membrane, then the hole might be relevant, as when playing a djembe you can insert or remove a fist in the hole to change the pitch of the drum.
Gluing/nailing: see http://caseyconnor.org/jl/cajon?start=4 -- nailing or screwing into the edge of standard laminate plywood doesn't really work, so you basically need to glue. Ocana also recommends this for the sake of a good air seal via the glue. The exception, sometimes, is the tapa, which you screw into the frame (the frame is in turn glued to the inside of the plywood). Some people also glue the tapa, but i prefer to leave mine removable.
@Richard - Yeah, generally the back panel is the same as the sides, with 12mm or thicker plywood (glued all around). It's important that the cajon be sturdy/rigid. Regarding the snares, see http://caseyconnor.org/jl/cajon?start=6 ... I agree that the string-snares are not satisfying. There are a number of other ideas on that page, as well as links.
Glad the site is helpful,
-Casey
My original design borrowed your first snare idea, but across one corner only thinking that I could have a 'slap + snare' corner plus a 'slap only' corner. The snares were not very successful: if given a lot of tension they produced a distracting sort of hum. Now I have them slack and with a few loose wires wrapped around which is OK played lightly but I am working on alternatives and will post here if I have a breakthrough.
I did find that there was a nasty resonance from the back panel even though it was well screwed on, and cured that by using frameseal (the stuff that goes around window frames) applied from the inside (with the Tapa removed). I also glued a chunk of MDF to the inside of the back panel to deaden it. The bass seemed more solid after that.
Just for fun, we put an ordinary cheap PC mic inside it and played it through a computer sound card: if you want to hear that, and see the cajon, go to youtube.com/expertanswers.
Even without a microphone I am amazed at the range of sounds and dynamics you can extract from what is just a box.
Thanks
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I am thinking about building my own canjon and your experience will be very helpful I think! Can't you create a blog or something like that and share your experience? I'm sure there is many people that will appreciate!
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Yeah same here!
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-Casey
Like i said am not a pro or anything else but love the sound of this instrument.
The one i built is 18 inches tall by 12 inches wide. i did not install any type of resonating devices in it, just pure sound from what the tapa (face) would make.
I use it for the first time today at church, like i said am not a pro, but i got good results.
Thank you for all the vital information you have share with everybody else.
Thanks