I would imagine it comes down to the recipes used for poly sheet materials. Maybe the type used by Peerless and some others has better self-damping properties, but costs a bit more.
@Tom_S said:
I would imagine it comes down to the recipes used for poly sheet materials. Maybe the type used by Peerless and some others has better self-damping properties, but costs a bit more.
The peerless HDS poly’s were well regarded, also the SB poly cones. But I haven’t used either, so could be talking out my ass. Wouldn’t be the first time. 🤷♂️
The AC130F1 is more than poly, and has glass fibers in it. You can see them from the surface.
The poly-mica is something several mfr have used, including Wavecor and Dynavox. I think it has a mica mineral powder additive, kind of like the talc-filled poly does.
Dynaudio calls it Magnesium Silicate, Morel calls it Damped Polymer Composite, but both are talc-filled-polypropylene. This just means the additive powder is spread out in the poly beads before injection molding takes place. The word "filled" is not really all that accurate, IMO.
I used to work in plastic injection, so I learned a lot about these processes.
Well then, this is not exactly what you want to read on a lazy Sunday morning that happens just as you're into the home stretch on a pair of HDS 830874 (poly cone) x HiVi RT1.3WE 2-ways. Not exactly ground-breaking in 2025, but I think I'll be okay. Whatever converts inventory into giftables.
Additionally, some manufacturers may vacuum-form their poly cones. Essentially, the plastic is molded into sheet goods because it is easier than molding the cone forms. Then they place the sheet in a device that clamps the rim while adding heat until the plastic softens a bit. Then the plastic forms to the die underneath when the vacuum is kicked on. I actually got to do some vacuforming back in 8th grade for a class project. Once the cone is formed, most companies have a fixture they set the forms in. This then stamps like a die press with a cutter blade or die to trim to the spec diameter.
Tidbit about the Dynaudio cones; the slots at the base of the cone are for the motor gap alignment. There are wires inserted vertically through them before assembly. Once the parts are put together, the wires keep the gap at tolerance to the voice coil. The driver cures, they remove the wires, and fill the holes with resin to seal them. I don't know if the Dynavox are done this way.
Comments
I would imagine it comes down to the recipes used for poly sheet materials. Maybe the type used by Peerless and some others has better self-damping properties, but costs a bit more.
I really liked the poly cone Dynaudio drivers I used (17W75XL?)
I have never heard anything bad about the Aurum Cantus AC-130F1.
The peerless HDS poly’s were well regarded, also the SB poly cones. But I haven’t used either, so could be talking out my ass. Wouldn’t be the first time. 🤷♂️
Now that I think about it, I haven't used a pure poly driver either. They call the Dynavox LW6004 a Poly coated Mica cone, whatever that is.
The AC130F1 is more than poly, and has glass fibers in it. You can see them from the surface.
The poly-mica is something several mfr have used, including Wavecor and Dynavox. I think it has a mica mineral powder additive, kind of like the talc-filled poly does.
Dynaudio calls it Magnesium Silicate, Morel calls it Damped Polymer Composite, but both are talc-filled-polypropylene. This just means the additive powder is spread out in the poly beads before injection molding takes place. The word "filled" is not really all that accurate, IMO.
I used to work in plastic injection, so I learned a lot about these processes.
InDIYana Event Website
Well then, this is not exactly what you want to read on a lazy Sunday morning that happens just as you're into the home stretch on a pair of HDS 830874 (poly cone) x HiVi RT1.3WE 2-ways. Not exactly ground-breaking in 2025, but I think I'll be okay. Whatever converts inventory into giftables.
That should be a great combo!
Additionally, some manufacturers may vacuum-form their poly cones. Essentially, the plastic is molded into sheet goods because it is easier than molding the cone forms. Then they place the sheet in a device that clamps the rim while adding heat until the plastic softens a bit. Then the plastic forms to the die underneath when the vacuum is kicked on. I actually got to do some vacuforming back in 8th grade for a class project. Once the cone is formed, most companies have a fixture they set the forms in. This then stamps like a die press with a cutter blade or die to trim to the spec diameter.
Tidbit about the Dynaudio cones; the slots at the base of the cone are for the motor gap alignment. There are wires inserted vertically through them before assembly. Once the parts are put together, the wires keep the gap at tolerance to the voice coil. The driver cures, they remove the wires, and fill the holes with resin to seal them. I don't know if the Dynavox are done this way.
InDIYana Event Website
The Peerless 874’s are my favorite ones, great driver and easy to work with.
https://www.jfcomponents.com/
Well, barring unforeseen snafus, they should be presentable in Ankeny.
The Peerless poly cone is top notch.