As to the original question i would build with quality plywood (i expect 15mm would be fine), but i would fix the bracing which is not well done.
This study leads to this general rule: the subpanels produced by adding a brace should have a higher aspect ratio than the panel being braced. Corallary: do not space the braces evenly.
In the anthology as better box could be done by orienting the braces vertically. I also like to brace the drivers to the back of the box (at least the woofers). This distributes driver vibrational rective energy to way more box maning the vibrational box load for any unit volume of box material to be less.
The construction seen is common and not nearly as effective as it could be.
Here is an example of an over the top box i did… note that it is larger thasn Anthology. Not necessarily clear, there are no braces parallel to the baffle just behind the driver.
dave
This study leads to this general rule: the subpanels produced by adding a brace should have a higher aspect ratio than the panel being braced. Corallary: do not space the braces evenly.
In the anthology as better box could be done by orienting the braces vertically. I also like to brace the drivers to the back of the box (at least the woofers). This distributes driver vibrational rective energy to way more box maning the vibrational box load for any unit volume of box material to be less.
The construction seen is common and not nearly as effective as it could be.
Here is an example of an over the top box i did… note that it is larger thasn Anthology. Not necessarily clear, there are no braces parallel to the baffle just behind the driver.
dave
Wow my brain is getting bigger with every read on this forum. I'll be going with plywood. Probably with beech as it's more dense, hard and heavy compared to birch. Also I'm not sure if the birch in croatia is baltic birch, as it's not mentioned anywhere. It's also surprisingly not expensive so why not. I was planning on changing the butt joints to rabbet or miter joints. That would would improve the robustness of the enclosure quite a bit. Do you think it would be worth it? Keep in mind I'm planning on using the speakers as my coffin in 50 years or so.
Here in Germany the prices of birch plywood went up since the Ukraine War. Now days birch plywood costs the same as Beech. Beech used to be about 40% more expensive.
BTW, living voice Kevin Scott build his higher grade speakers (Vox) also out of Beech, I saw a video of him explaining his decision but I forgot which it was.
If it's good for the Living voice Vox olympian it's also good for me 😀
BTW, living voice Kevin Scott build his higher grade speakers (Vox) also out of Beech, I saw a video of him explaining his decision but I forgot which it was.
If it's good for the Living voice Vox olympian it's also good for me 😀
Important phrase is ‘quality plywood’. The cheap one is so bad it it seams like pure waste of Wood. Veener side thinner than paper. All kinds os disgusting materials between layers etc.
Good quality feels like real Wood and Smell like it when you Saw it.
I will never again build a cabinet from MDF. Dust is disgusting. Of course one could build OK cabinet with MDF, but IMO life is too short to use that material.
Fronts I prefer HDF. Dust is still insane, but is easy to form and think it is less resonant than ply.
Good quality feels like real Wood and Smell like it when you Saw it.
I will never again build a cabinet from MDF. Dust is disgusting. Of course one could build OK cabinet with MDF, but IMO life is too short to use that material.
Fronts I prefer HDF. Dust is still insane, but is easy to form and think it is less resonant than ply.
How did you calculate the volume of the bracing? Hay per acre is pretty easy. 😁As to the original question i would build with quality plywood (i expect 15mm would be fine), but i would fix the bracing which is not well done.
This study leads to this general rule: the subpanels produced by adding a brace should have a higher aspect ratio than the panel being braced. Corallary: do not space the braces evenly.
In the anthology as better box could be done by orienting the braces vertically. I also like to brace the drivers to the back of the box (at least the woofers). This distributes driver vibrational rective energy to way more box maning the vibrational box load for any unit volume of box material to be less.
View attachment 1313975
The construction seen is common and not nearly as effective as it could be.
Here is an example of an over the top box i did… note that it is larger thasn Anthology. Not necessarily clear, there are no braces parallel to the baffle just behind the driver.
dave
The braces i use are targeted to have a third of the panels are holes, so an 18mm thick piece has an effective width of 12mm. Then, given the dimensions of the unbraced box i will increas ethe width by 12mm if i use a single baffle to back brace.
If ii need to be realanalithe CAD program calculats it.
dave
If ii need to be realanalithe CAD program calculats it.
dave
The important thing is designing an enclosure with a shape such that it does not rely on excessive bracing. A cuboid as most often employed is the worst possible starting point!
My new 21" subs are being built in 15mm ply with minimal 6mm bracing.
The supplier I contacted about the beech plywood turns out doesn't have beech plywood in stock, but he has "bukva/eukaliptus twin B/BB" which translates to "Beech/Eucalyptus twin B/BB". Does that mean that the veneer is beech and the inside is eucalyptus, or that the layers alternate? I'm really confused about the "twin" part. And does that even sound like a good option? It's quite cheep as well 19 euro per square meter. I'm rly want to go bunkers with the construction and I'm worried if this is going to cut it. Anyone have opinions on the wood?
That mixed eucalyptus + some other wood stuff has only appeared in the last few years, possibly to fill in for the no-longer-available second-rate Soviet birch. The kinds I've seen were rather soft and of varying quality, ok for test enclosures, or kitchen cabinets, but not a fit for the premium build you aim for.
Good quality birch is really the stuff to use. I find beech a lot more difficult to work with, as it has a stronger tendency to warp. While stronger than birch, the latter is plenty tough, and usually comes in a higher ply count.
PS - I have never not regretted using MDF. It is an annoying and frustrating material. What other material turns to mush at the glue joints until that glue has set, one day later? The only use I have for it now is as sacrificial layer when using the cnc-router.
Good quality birch is really the stuff to use. I find beech a lot more difficult to work with, as it has a stronger tendency to warp. While stronger than birch, the latter is plenty tough, and usually comes in a higher ply count.
PS - I have never not regretted using MDF. It is an annoying and frustrating material. What other material turns to mush at the glue joints until that glue has set, one day later? The only use I have for it now is as sacrificial layer when using the cnc-router.
Seems to be a second grade material. Very cheap price, I am paying more then double for my plywood.
Here in the photo you can see a good quality 47mm birch plywood
It is advisable to first build test cabinets and keep these for a little longer time, then when you get to know them decide
on how expensive finish/materials should be. Novice DIYers tend to change loudspeakers rather frequently. And when you try to sell expensive cabinets, it's only the seller who finds it worthwhile.
Sheep's wool is the favoured foodstuff of some moths. I bought some speakers a few years ago and when I opened them up one had wool damping, while the other had no visible wool, just lots of horrible dust. It was everywhere, all over the drivers, even in the voice coil gaps. It turned out some moths had got in and eaten all the wool. The dust was their poo. (Frass is the technical term in English.) So I'd recommend wool that's been treated with insecticide. 😁
I really like natural wool stuffing... but I only use it in sealed box applications. In other words, midrange enclosures, and sealed box woofers. I would be reluctant to use it in a vented box, just as @ianbo warns against.
@Lojzek I'm affraid it's a one and done situation with me, as speakers are one of a bunch of things I gotta make and acquire, so doing it as right as possible first try is what i'll try to do. From then on it's just me placeboing myself into thinking I built the best speakers in the world. Right now I'm trying to get as educated as possible on the topic before jumping on a different project.