I was currently thinking, why are there few subwoofers with a cone made of wood?
Maybe it's for reasons of weight and resistance, or because it's difficult to make a concave cone shape in wood.
But without talking about the problems with making the cone, what would make a wooden cone a good choice for a the subwoofer?
And why not manufacture the wooden cone, in a flat format?
Maybe it's for reasons of weight and resistance, or because it's difficult to make a concave cone shape in wood.
But without talking about the problems with making the cone, what would make a wooden cone a good choice for a the subwoofer?
And why not manufacture the wooden cone, in a flat format?
Right, for the LF, a flat disc is fine if made sufficiently rigid/massive/damped, i.e. PR woofer; otherwise cone is best where relatively light weight, high damping is desired.
It has a very low specific modulus along with low tolerance for stress with loads perpendicular to the grain.
My question is about wood veneer, not wood pulp which is the material used to make the paper cone.
I was thinking about MDF with epoxy resin.
the resin only to avoid humidity problems and aesthetic issues.
Adding to the others' comments, I think wood veneer would commonly be less consistent between samples than other materials due to natural variances and weaknesses in the grain. JVC made a couple of wood coned speakers some time ago...here's part of a review:
JVC pursued wood as a speaker cone material because it provides an ideal combination of high sound propagation speed and natural vibration attenuation (internal loss), allowing the speakers to naturally reproduce a wide frequency range. With conventional paper cones, sound spreads at the same speed in all directions, causing unnatural resonant points with limited frequency response. Wood cones produce few resonant points because of the grain, so frequency response is improved and sound quality is significantly enhanced. JVC engineers tried several types of wood, but birch proved to have the best acoustic properties.
JVC’s wood cone speakers were 20 years in the making because forming the wood sheets into a speaker cone proved daunting – they would crack or split when stamped. The solution turned out to be sake – Japanese rice wine. A JVC audio engineer in Japan hit upon the sake solution while enjoying dried squid at a restaurant. He asked if anything special was done to make the dried squid so chewy. It was soaked in sake, he was told. Inspired, the JVC team tried the same technique with the wood sheets. It worked – after soaking in sake, the sheets could be pressed into speaker cones without splitting.
Both JVC speaker systems are comprised of a pair of four-inch wood mid/bass drivers and a one-inch dome tweeter that uses a birch wood dome.
JVC pursued wood as a speaker cone material because it provides an ideal combination of high sound propagation speed and natural vibration attenuation (internal loss), allowing the speakers to naturally reproduce a wide frequency range. With conventional paper cones, sound spreads at the same speed in all directions, causing unnatural resonant points with limited frequency response. Wood cones produce few resonant points because of the grain, so frequency response is improved and sound quality is significantly enhanced. JVC engineers tried several types of wood, but birch proved to have the best acoustic properties.
JVC’s wood cone speakers were 20 years in the making because forming the wood sheets into a speaker cone proved daunting – they would crack or split when stamped. The solution turned out to be sake – Japanese rice wine. A JVC audio engineer in Japan hit upon the sake solution while enjoying dried squid at a restaurant. He asked if anything special was done to make the dried squid so chewy. It was soaked in sake, he was told. Inspired, the JVC team tried the same technique with the wood sheets. It worked – after soaking in sake, the sheets could be pressed into speaker cones without splitting.
Both JVC speaker systems are comprised of a pair of four-inch wood mid/bass drivers and a one-inch dome tweeter that uses a birch wood dome.
Ted Jordan who promoted metal cones once said that if money would have been invested into making plastic loudspeaker cones like into the development of plastic bags we would have had loudspeaker cones with perfect properties.
So wood can be optimized but it takes money, science and engineering to do so.
I dream of a Polystyrol honeycomb material CNC machined and duraluminium sandwich cone on it.
My simple diy approach is aluminum foil on paper cones.
https://www.diyaudio.com/community/threads/how-to-make-a-loudspeaker-sandwich-cone.402917/
Here with 15inch Fane fullrange driver
So wood can be optimized but it takes money, science and engineering to do so.
I dream of a Polystyrol honeycomb material CNC machined and duraluminium sandwich cone on it.
My simple diy approach is aluminum foil on paper cones.
https://www.diyaudio.com/community/threads/how-to-make-a-loudspeaker-sandwich-cone.402917/
Here with 15inch Fane fullrange driver