congaplace.com

wooddrum wrote:... they´re standing much safer when you play them together with traditional congas.

wooddrum wrote:... (we know, its all about technique with this kind of drums)

p.a.dogs1 wrote:Hi smackdaddy, I built several cajones in the last years and I am still experimenting with measures and materials. There are some things I found out (maybe ):

1.Every single piece of wood has specific sounding properties. The birch plywood you buy today is different from what you´ll get one week later. I don´t know from where the wood comes in the USA, but here in Germany it comes either from Finnland or from Sibiria. The finnish quality is generally more white with a rather accurate surface, the sibirian quality is often more yellow and the surface sometimes a little splintery. Seen from the aspect of sound I prefer the sibirian quality for playing boards - as someone, who likes to work with wood, I prefer the finnish quality.

2. A cajon´s functionality is the same as other kinds of drums: one part is swinging (skin) and another part (shell) constitutes the counteracting force. Among drumset-builders there is a permanent discussion, if shells have to be thick or thin for better sounds. Beside the question of proportion you should decide, if you want to have a sound, where the sides are involved in producing it´s charakter, also depending how much contact the instrument has with your body (legs). Then you should choose a rather thin plywood (8mm or 9mm - maybe 6,5mm with supporting ledgers). If you prefer an independent sound, no matter if you have it between your legs or if it stands seperated, you should choose a thick plywood - 12mm, possibly 15mm (but birch would make the instrument very heavy).

3. The proportion. I found out that a cajon does not need to be such tall (29"). 25", 26" or 27" is enough, when you keep it up a few centimeters with your feet. Watching Daniel Aldama El Bonkoiro in the first of RitmoBoricua´s clips you see that tones are produced with a technique which is similar to how congaplayers produce muffled tones. The hands come from more above. I am rather sure, that I found out some rules for proportions with 9mm birch plywood and a tallness of 27".

smackdaddy wrote:I am not interested in open tones or even the concept of it being "conga-like". I only want it to sound like the cajons I hear on many rumba recordings, with that long sustaining bass tone. That is my quest, and I have made several attem,pts at it, only to come up kinda short.

Almost open tones are produced by hitting the cajon very close to the edges of the playing board. You can say, that it is more or less the body below the playing board which makes the sound´s character (similar to accented muffled edge-tones on a macho). Therefore you can also think about taking a thick poplar plywood (15mm, 18mm) for the body, which is not as heavy as birch, but gives rather clear tones. The disadvance of poplar is it´s bad surface quality.

For a long sustaining bass you need a rather thin playing board (slow frequency) of plywood with a high specific weight and density (the more mass the higher the amplitude and the longer it swings). In Europe we have beech plywood in different qualities (more ore less heavy) and prices up to more than 50 euros per squaremeter. For open tones thicker playing boards of plywood with low specific weight and density (poplar) are often better. A width of 19" is really large. My favorite cajon is 36 cm (14,4") with 9mm birch plywood for the body and 2,5mm beech plywood (5 plies) as playing board.

I recommend reinforcement ledgers at the top edges of the cajon. This gives an additional stability and you can fix the playing board with some screws. Otherwise heavier bass hits can stress it too much by and by (especially when it is rather thin and the edges are possibly not perfectly plane to each other).



p.a.dogs1

p.a.dogs1 wrote:Seems to be the beginning of a lifetime obsession .

Are you sure that the oak plywood is really oak? Those thin sheets are mostly defined by only the cover plies. For the inner plies the producers use different and much cheaper wood. This material - also called "veneer plywood" - has more decorative functions (backsides of cabinets etc.) not constructive functions. Therefore it is not important from what material the inside is made - that means: it varies depending on what is just available (and regarding sounding attributes).

There is a constructive quality which is called "multiplex": all plies are of the same thickness and of the same kind of wood. But this quality starts from 9mm (ca. 1/3") in birch and from 12mm (ca. 1/2") in beech. Another quality is the so-called "modeling-plywood" (or "airplane plywood") which you can get with 5 plies (à 0,4mm) from 2mm thickness in birch or beech.

Regarding thicknesses of tops I would generally agree. But what you tell about birch and oak qualities makes me sure, that your oak is just a veneer plywood (probably the birch as well).

Another question: what sounds do you prefer? When playing lengthwise or crosswise the veneer?

p.a.dogs1

burke wrote:New project. Saw the laptop conga in a store and thought how hard can this be to DIY ? ... turns out not very.

Here are a few pictures of it during construction and a less poor sound clip than I posted earlier [I'm editing the post now]. I only had a cheap digital recorder and the technique of getting sound out of these is a bit different ... starting to get it however. My wife recorded it with her Iphone a few minutes ago and the sound quality is better than the first clip I posted.

https://dl.dropboxusercontent.com/u/20111806/Iphone.mp3

Pretty pleased overall. Cost was $20/25 bucks overall and a few hours of relaxing recreational time.