What Type of Wood Should I Choose?

[spaceman5]

Hi All


I am creating an enclosure for the TC9FD18-08 Full Range drivers.
I am buying the materials and have the ability to choose from various wood types.

What type of wood should I choose?


Is MDF the most recommended, like I mostly see?

Also, I have an art store near my home, and they sell there a type of wood called "Balsa", also called "Ochroma"
https://en.wikipedia.org/wiki/Ochroma

An externally hosted image should be here but it was not working when we last tested it.

Is it good too, for speakers?
(this type of wood seems to be very common in art stores)


Thank you

 

[Rundmaus]

The Balsa wood (at least the stuff sold here) is really soft, that's why it is useful for arts and crafting - easy to work with.

I would think it is not rigid enough to use it for speaker enclosures, but maybe someone more familiar with woodworking will give his opinion...

Regards,
Rundmaus

 

[Cal Weldon]

Plywood works well. As least as good as any I can think of.

 

[spaceman5]

Thank you Rundmaus and Cal Weldon


I forgot to write that my question is asked specifically from the sound quality side of the story..

Will some type of wood make the sound better than another?
And if yes, then which one is the best...

(I see MDF being used a lot, so I will not be surprised if sound quality wise, it is the best option,
but would definitely like to verify that before I buy the wood and start doing the cuttings..)

 

[jerryo]

Personally I would not use MDF as it is horrible stuff to use when machining. I have used it, but I always regret doing so afterwards. The resin that binds the fibres together is actually toxic and the fibres when airborne are very unpleasant. Tooling and finishing the cut edges are in particular unsatisfactory. A high quality 'multi-ply' board is perhaps the best choice. The wood should not contribute any sound character to the speaker, as it should be acoustically, as inert as possible.

 

[delange]

For speaker cabinets you need a rigid kind of wood. MDF is used widely, even by popular speaker manufacturers. An advantage of MDF is that it is easy to work with and it is easy to create a beatiful fininsh (for example when painting it).
However, MDF is not rigid. It is heavy and bends quite easy. You could see it as a kind of cardboard...
Better use plywood. You could use beech if you need a large enclosure with heavy speakers (for better stability). 18 mm is usually a good thickness.

What are the dimensions of your speaker enclosure?

 

[esprit]

I have been using "Birch Ply" (preferably Scandinavian) since the mid 70's. 1/2" for smaller enclosures and 3/4" for larger.
The BBC did some research on enclosure materials, at the time of the development of the LS3 5a, worth a look.
My last speaker enclosure has a laminate front baffle of mdf & birch ply, I have no science to prove this to be a superior construction, just playing around.
Whatever material you finally chose, rigidity is important.

 

[delange]

I have been using "Birch Ply" (preferably Scandinavian) since the mid 70's. 1/2" for smaller enclosures and 3/4" for larger.

I second this!
We've used 13 layered Finnish birch plywood for our professional speakers. This wood is very rigid and very suited for speaker enclosures. You can build enclosure as strong as a tank. Only thing is... you won't be popular with your carpenter... It is wood that is demanding on the cutting tools (saw, mil,...).

 

[Cal Weldon]

Uh guys? While what you're saying maybe applies in some cases, this is a 3.5" inexpensive FR speaker.
Depending on the finish, standard 4 ply, G1S, 1/2" ply will be just fine. It can be what's available in your local lumberyard.

Spaceman, the object of the game is to avoid the enclosure adding to the sound, or in the case of MDF, sucking the life out of it. 🙂

 

[GM]

Actually, as Qts rises, the cab's damping ability increasingly comes into play, so with such a high Qt, Balsa, foam core or even Styrofoam will work well.

GM

 

[simon7000]

Balsa is about 1/4 the strength of more common woods used for loudspeakers. It is easily worked as the only tools you will need are a razor knife, a steel ruler and wood glue. White or yellow glue is best.

Balsa | The Wood Database - Lumber Identification (Hardwoods)

Yellow Birch | The Wood Database - Lumber Identification (Hardwoods)

So if you use balsa that is twice as thick as a more common loudspeaker wood the results should be about the same except the enclosure will weigh half as much. Keep in mind balsa is a more expensive wood. The particular pieces you show are already finish sanded.

For a bit more advanced result you can laminate small pieces cross grained and make your own plywood. A couple of books should provide the clamping pressure during lamination glue up.

 

[spaceman5]

Thank you all for interesting answers!

What is the difference between Plywood and Milti-Ply?
When looking in Google Images, it seems that both look the same,
it's what we call here "sandwich" wood..
So is there a difference between the 2?


The drivers are 3.5",
each speaker will have 1 driver..
It is full range and I do not intend to add a tweeter.

You can see the driver here:
https://www.parts-express.com/peerl...-3-1-2-full-range-paper-cone-woofer--264-1062


It is meant to be used as near-field, as good computer speakers, for listening to music.

Because it is for music, the sound quality is the most important factor here..
It does not need really high rigidity since it does not weigh a lot..
(I do save your tips regarding rigid woods for a day that I will create something bigger)

Spaceman, the object of the game is to avoid the enclosure adding to the sound, or in the case of MDF, sucking the life out of it. 🙂

Do you mean by the second half of the sentence that MDF will suck the life out of the sound, or the opposite?

 

[spaceman5]

Actually, as Qts rises, the cab's damping ability increasingly comes into play, so with such a high Qt, Balsa, foam core or even Styrofoam will work well.

Interesting..

Never new what the Qt parameter meant, till now (went to read about it)

It does have a high Qt

An externally hosted image should be here but it was not working when we last tested it.

https://www.parts-express.com/peerl...-3-1-2-full-range-paper-cone-woofer--264-1062

So after all Balsa might be appropriate and even more appropriate than harder types of wood?
(as said, the stores around me enable me to buy quite various kinds of woods)

Balsa is about 1/4 the strength of more common woods used for loudspeakers. It is easily worked as the only tools you will need are a razor knife, a steel ruler and wood glue. White or yellow glue is best.

That's great.

Is there maybe a tool that enables one to create a circle hole in a wood,
with a specified diameter that is needed?

e.g., for this driver I need a 8.3cm diameter circle hole.
I can do it with a CNC machine, but a CNC machine is not something that you have at every home.. An tool with an adjustable diameter that enables to cut circle holes can be really useful for creating speakers.. (and will work really well with Balsa since it's more easily cut)

So if you use balsa that is twice as thick as a more common loudspeaker wood the results should be about the same except the enclosure will weigh half as much.

Cool

Keep in mind balsa is a more expensive wood. The particular pieces you show are already finish sanded.

Well, for small speakers it should not be a deciding factor, since the amount of wood needed is quite little..
(the pieces shown in the picture in the first post in this thread, are all 5$-10$)

Balsa | The Wood Database - Lumber Identification (Hardwoods)

Yellow Birch | The Wood Database - Lumber Identification (Hardwoods)

Really useful website for wood types, thank you 🙂

 

[simon7000]

For balsa wood you can use a beam compass that takes a razor knife blade. For harder wood a router with a circle cutting attachment.

 

[paul burchell]

For a bit more advanced result you can laminate small pieces cross grained and make your own plywood. A couple of books should provide the clamping pressure during lamination glue up.

HAHAHA Good luck with that.

 

[spaceman5]

For balsa wood you can use a beam compass that takes a razor knife blade. For harder wood a router with a circle cutting attachment.

Thank you

You know, lately desktop CNC machines are becoming cheaper..
It would be nice to have one at home, and to be able to make holes in any diameter easily 🙂

 

[dischoe]

For a bit more advanced result you can laminate small pieces cross grained and make your own plywood. A couple of books should provide the clamping pressure during lamination glue up.

HAHAHA Good luck with that.

I seem the making of plywood they set TONS of clamping force on it.

The thin high ply cound plywoods are what I like to use. I used to build stuff with MDF that became a distant thing of the past.

 

[Cal Weldon]

Do you mean by the second half of the sentence that MDF will suck the life out of the sound, or the opposite?

When comparing the sound of MDF with other materials in identical systems, I like MDF the least.

 

[spaceman5]

When comparing the sound of MDF with other materials in identical systems, I like MDF the least.

Wow, surprising,

It's good that I asked then..
Because so far I have seen MDF so widely used for speakers..

The thin high ply cound plywoods are what I like to use. I used to build stuff with MDF that became a distant thing of the past.

What is cound plywoods?
And what is high ply?

 

[Cal Weldon]

Yes, MDF is used because:
1. It doesn't have to be structural.
2. It is inexpensive.
3. It is easy to work with.
4. It's appearance is immaterial as it is covered.
5. The difference is not big enough to discourage manufacturers.