HiFi Subjectivist ¦ Audio Forum ¦ NVA User Group

As the title. Wood is good apparently- sounds natural It's not a good idea to build your speaker out of real wood unless you really know what you are doing - that rules out everybody here

Why don't we build our stuff out of dried shit. What would it sound like ? Most cube users speakers sound like bullet proof vest combined with plastic I have my metal 2" drivers in a plastic sphere and I'm fooked if I know what it sounds like.

Then when we get on to speaker cone material. Paper is the darling of the voice loving population and I don't deny it sounds like that boring book you couldn't be arsed to finish reading. So kevlar sounds like bullet proof vests- have you ever heard one. Plastic sounds like cack and so artificial 1970's like. Metal sounds like well....CN's record collection What the hell does fibre glass or carbon fibre sound like ? Lightweight bicycles ?

What about when you mix it up ? One paper driver and another metal ? Is it like that boring book you couldn't be bothered to finish when suddenly CN explodes into the room with his boombox playing Anthrax ?

Yours non the wiser of North Yorkrshire

No mention of speaker stand material. No prizes for guessing what mine are made of and they weigh a tonne.

Why is it (considered) a bad idea to make speaker cabinets out of "real" wood? As in solid timber?

I always thought it was down to cost that MDF is used by so many companies.

I can see the advantages of high quality plywood, due to the mulitlayers.

Is not the keyword here 'Resonance'?

The effect of a solid cabinet material on the sound from a loudspeaker depends on how much that material resonates along with the vibration of the driver.

The more 'dead' an enclosure is - the less influence ir will have on the resulting musical performance.

Real timber gives that warm 'woody' sound, my Arcam's are solid wood, not MDF.

Lindsayt wrote: ↑Fri Oct 29, 2021 10:11 pm Why is it (considered) a bad idea to make speaker cabinets out of "real" wood? As in solid timber?

I always thought it was down to cost that MDF is used by so many companies.

I can see the advantages of high quality plywood, due to the mulitlayers.

Real wood moves, expands, contracts, cracks with changes in humidity. Speaker drivers are a source of heat especially if you are thrashing them ina sealed enclosure which traps heat. Plywood is much more stable due to the plys running in different directions and it is also stronger and bends less than real wood when presented with internal pressure from drivers in a sealed box.

I did a lot of reading on this a while back. Almost everyone advised against using real wood for the above reasons plus real wood colours the sound more than plywood. Thats why many of them are called tone Woods. MDF is used for cost reasons of course and imo is not the best option. Baltic void free Birch ply is the best option.

If I was going to make a speaker enclosure out of solid wood I would ensure it is extremely well seasoned and stored in the room it will be living in for a while before making it. I am reminded of the solid oak worktop I had over a washing machine that bended like a banana.

Fretless wrote: ↑Sat Oct 30, 2021 7:12 am Is not the keyword here 'Resonance'?

The Blutac between my heavy metal stands and speakers provides damping as well as stability.

If I had the cash spare I would run out and buy a pair of Diapason speakers.
Solid seasoned Walnut blocks, hollowed out, minimal crossovers and doped drivers.

I have heard them and they are awesome.

So, on the solid wood front, a more dimensionally stable wood like Accoya might be OK?

Or you can go down the over-engineering route, as per the hewn from tree-trunks Diapasons?

Lindsayt wrote: ↑Sat Oct 30, 2021 11:34 am So, on the solid wood front, a more dimensionally stable wood like Accoya might be OK?

Or you can go down the over-engineering route, as per the hewn from tree-trunks Diapasons?

I am far from an expert on these things. If it's more stable then that has to be good. Clever carpenters can allow for shrinkage and expansion in their work but I don't know how they do it or whether it transfers well to something that has to stay air tight and is trapping heat. I really have no idea how hot it gets in a sealed wooden speaker enclosure. Wood is a poor conductor of heat.

Don't let me put you off Lindsay, I just wanted to make you aware of things that COULD happen so you can take it into account when planning. I love the idea of real wood speakers but I don't think I could pull it off. For the size of speakers you are planning then there are going to be a lot of different planks to join. I think quarter sawn is the stuff to go for.

I am sure you will get better advice if you ask the right people.

I am intrigued by the sound of different materials used in speaker driver manufacturing. There really are lots of different ones used. Paper, plastic, metal, carbon fibre, fibre glass, kevlar, hemp and probably others I have forgotten. I am not in a position to try them all so have to wade through opinions on the Internet.

My B&W speakers use kevlar mid bass and aluminum tweeter. I think the worst thing about kevlar is the strong break up modes higher up. A bit of blue tack works wonders. Metal domes get a bad press, many moan about the metallic edge they can have but they have some endearing qualities.

My little 2' metal cone with plastic dome in the centre does not sound objectionable at all imo. I don't have any paper coned drivers at the moment to compare. Kevlar is OK if the break up is damped mechanically. You can do it electrically ofc but I don't think notching it or relying on it being out of band is very effective.

It gets even more interesting when multiway speakers are considered. If the filters are first order then the drivers are producing the same frequencies over a very large overlap. I wonder if if is considered best to try and stick to the same material for each driver as much as possible. Or can we be cunning and combine the sounds of two different materials to our advantage ?

I remember trying to dope an aluminum continuous cone 5" mid bass and it was a complete failure, it sounded very nasty. I would only consider it for a pure bass driver where the break up is many octaves out of band. Even then, I believe these break ups can have consequences lower down in frequency where it is often in the driver pass band.